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CORNELL UNIVERSITY

wecmder bl UNIVERSITY LIBRARY

Cornell University

Library

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Cornell University

Library

OF THE

Wew Work State College of Agriculture

FARM FRIENDS. AND
FARM FOES

A TEXT-BOOK OF AGRICULTURAL SCIENCE

BY

CLARENCE M. WEED, D.Sc.

STATE NORMAL SCHOOL, LOWELL, MASSACHUSETTS

D. C. HEATH & CO., PUBLISHERS
BOSTON NEW YORK CHICAGO
$e} Ce)

CoPyRIGHT, 1910,
By D. C. Hzatu & Co.

PREFACE

Tus book is intended to serve as a text and guide for
the study of those plants and animals so vitally related to
crop production as often to determine success or failure
therein. The information given embodies the latest re-
‘searches of that host of investigators who have done such
great service in the advancement of agriculture in recent
years. The text has been so combined with directions for
observation and expression that it is hoped that teachers
will be able to lead their pupils to a first-hand knowledge
of the most important plants, insects, birds, and mammals
to be found in the region of the school.

Most of the original engravings are from drawings by
Mr. W. I. Beecroft, a few being adapted from the publica-
tions of authors to whom credit is given in the list of illus-
trations. Many of the insect pictures are from woodcuts
originally made for the classic report on /msects Injurious
to Vegetation, by Dr. T. W. Harris, for the use of which
thanks are returned to Mr. J. Lewis Ellsworth, Secretary
of the Massachusetts State Board of Agriculture. For
courtesies in connection with other illustrations I am in-
debted to Misses Hazel Dearth, Alice Manning, and I. S.
Cragin, and Messrs. James Hall, A. I. Randall, E. D. San-
derson, A. D. Selby, A. H. Verrill, and C. W. Woodworth,
as well as to the Experiment Stations of Illinois and New
Hampshire and the United States Department of Agri-
culture. I have also to thank Mr. W. F. Fiske, of the
Gypsy Moth Laboratory, for kindly reading the proof of
the chapters on Predaceous and Parasitic Insects.

Cc. M. W.

CONTENTS

PART I
FRIENDS AND FOES AMONG THE WEEDS
CHAPTER : PAGE
I. THE WEEDS OF ROADSIDES AND WASTE PLACES . . 3 I
II. THE WEEDS oF MEADOWS AND PASTURES . ‘ F se gs
HI. THE WEEDs OF GARDENS AND CULTIVATED FIELDS . - 31
IV. THE: WEEDS OF GRAIN AND FORAGE Crops . 2 7 - 45
V. THE Economics oF WEEDS . - : - 2 7 - 55
PART II

FRIENDS AND FOES AMONG THE INSECTS

VI. ORTHOPTERA: THE GRASSHOPPERS, CRICKETS, AND COCK-

ROACHES. é F : : : - 65
VII. HEMIPTERA: THE TRUE Bues: 5 6 5 zs . 2» 73
VIIT. THE BUTTERFLIES AND MOTHS . : 3 : 3 - 96
IX. THE Two-wiINGED FLIES . 7 . . 122
X. COLEOPTERA: THE BEETLES . - - 131
XI. HYMENOPTERA: THE ANTS, BEES, WKEES, AND + Swe - 149
XII. INSECTICIDES AND THEIR APPLICATION . . . . - 155
XIII. THE Prepaceous INsEcTs . . ‘ i 2 ‘ - 163
XIV. THE Four-wWINGED PARASITES , : . - - - 174
XV. THE Two-wINGED PARASITES = . - 188
XVI. THE POLLINATION AND Hiaanieensai & OF Wouwens ‘ - 194
XVII. THE INsEcT POLLINATORS. : - . . . + 203
PART III

FRIENDS AND FOES AMONG THE FUNGI

XVITI. THE MusHROoMS, TOADSTOOLS, AND MoLps . : + 215
XIX. THE Downy MILDEws . 3 - - : : 4 - 219
XX. Tue Smut Funcl . . . . + 2 «© + « 226

XXI. THE Rusts. : . sie é : ‘ : - 231

vi

CHAPTER

XXII.
XXIII.
XXIV.

XXV.
XXVI.

CONTENTS

THE ASCOSPORE AND OTHER FUNGI .
BACTERIAL DISEASES OF PLANTS.
PREVENTIVES OF FuNGous DISEASES .
Funcous DISEASES OF INSECTS .
BACTERIA AND PLANT Foop

PART IV

FRIENDS AND FOES AMONG THE BIRDS

XXVII.

THE RELATIONS OF BirDS TO FRUIT ORCHARDS

XXVIII. THe RELATIONS oF BIRDS TO MEADOWS AND PASTURES

XXTX.,

FRIENDS AND FOES AMONG THE

THE RELATIONS OF BIRDS TO GARDENS AND FIELDS

PART V

XXX. THE SQUIRRELS
XXXII. THE MIcE AND Rats . F - 5 : .
XXXII. THE Rassits, Pocker GopHers, MOLES, AND SHREWS

BIBLIOGRAPHY

INDEX

MAMMALS

PAGE
242
229
264
271
275

285
291
296

307
312
321
328

329

LIST OF ILLUSTRATIONS

Monarch Butterfly. From Nature Biographies . : 2 é - xi
Cover Design for Booklet. From a Japanese Stencil . : . . 2
Dandelion Seedheads . . 7 F 3 7 s ‘ : . 5
Burdock E a “ : $ : : ‘i . . . : 7
Broad-leaved Dock : : 3 4 ‘ F : . é 8

Evening Primrose . . . = : : . - - 10
Toadflax or Butter-and-Eggs . : . 3 : - . : 3 EE
Milkweed Pods . ‘ F ; . = 2 «33
Sprig of Johnson Grass. Febiee from Cates and Spillman - - 4
Squirrel-tail Grass . . F : ‘ é F 7 3 - 15
Cone-flower . ‘ ar 7 2 . . é 5 - 16
Canada Thistle . 7 : - : - 7 . 3 ‘ - 18
Milkweed Seeds. : : . - oe a ee eee

Sheep Sorrel . E c 5 . . . : . . . - 22
Hardhack . F . . 3 2 . . : . . 2 24

Poison Hemlock . é 5 . : » 26
Poison Ivy. From Dray i ve L. Randall : 7 5 F 127
Quack Grass . . ae. 2 z . 7 - - se SBI
Pigeon Grass . 3 : : % : : . oe > 132
Shepherd’s Purse . 5 . . is - : - . 2 aS N33
White Pigweed . : ‘ é . j ‘ 7 . a - 35
Ragweed Fs . A : . : . . 5 . . - 37
Clotbur . 7 . . 5 : . . . . - 38
Ground Cherry or Physalis . 7 4 5 ‘ . . ° + 40
Jimson Weed. ‘5 . : : : a : F . - 4!
Gill-over-the-Ground . - 44
Mixture of Weed Seeds. Haw U. S. Deporiment of Aeviniiute - 46
Meadowsweet . ‘ . ° . . . . - 55
Spud. . . . 7 . - 56

Broad-leaved Tock. mucin om Bakeh, . ie fl) - 59
Goldenrod Seedheads . . : : : ‘ . s . - 61
Cover Design for Booklet on Insects . 3 ° 7 s . . 64
Mouth Parts of Grasshopper . - s : : * . . 66

viii LIST OF ILLUSTRATIONS

Grasshopper: Nymph and Adult . : i!) <3 .
Oblong Leaf-winged Grasshopper. From Harris. . i 3
Common Cricket. Female. From Harris . 7 $ ‘ r
Tree Crickets: Male and Female. From Harris. $ 5 :
Mole Cricket. From Harris. A : 3 3 . Fi :
Squash Bug . Be oa ve . aos ee ee ee :

Chinch Bug. From Harris . . 7 : 7 = .
Map showing Distribution of Chinch — After Webster .
Periodical Cicada . 7 - 7 . . . . . .
Tree Hoppers. From Harris . . . . . . .
Scale Insects on Rose . . . . ‘ ‘ . 2
San José Scale. : . : . . ‘ s
Black Scale . . 7 ‘ . . . F c s

Spring Grain Aphis. Redrawn from Webster . . . 7
Eggs of Apple Aphis. : i é ; ° ‘ - a
Ant attending Aphides . . ‘ 5 3 : ‘ -
Elm Leaf affected by Aphides ‘

Cicada emerging from Nymph Skin. Phomeraph ye A. ‘. Verrill
Promethea Moth Cocoon . .
Orange-dog Caterpillars. Pharograph iy A, H. Verrill. s
Butterfly of Orange-dog rage a Photograph by A. H, Verrill

Luna Moth . . ‘ : : . . "
Tent Caterpillar . E . - 7 - . : -
Gypsy Moth . 3 3 . . . : : : F ‘
Army Worm . . . . . é . c .
Cutworm Larva. . From Haerii . 5 -

Cotton Bollworm. Photograph by A. a Verrill 3 4 3 :
Codling Moth < 7 . : 5

Apples showing Calyx Open pud Calyx Chesed 3 F . -
Leaf Roller Moth. From Harris 3 ‘ $ . . 2
Peach-twig Borer. After Clarke . . "i ‘ : s .
Tineid Moth . d F . : : . : - c
Winter Nest of Brown-tail Moth : . a. . :
Hessian Fly . . ‘ . = 6 ‘ é 5

Hessian Fly Magnified . : F : 5 é é
Apple Maggot . ‘ 7 - . os 8 . .
Channels of Apple Maggot . 7 : . . :

Cabbage Maggot. Adapted from Westieie P é .
White Grub or May Beetle . fi . F . .
Lamellicorn Beetle. From Harris : - F
Potato injured by White Grub ° A . .

LIST OF ILLUSTRATIONS

Rose Chafer. From Harris. ie ci> te Ty TR RY ox
Eyed Elater. From Harris - 3 c . - : . :

Leaf Beetle. From Harris . : . F : . : .
Colorado Potato Beetle . . : : F 3 ‘ - .
Flea Beetle . : . : 7 7 z : .
Round-headed Apple-tee Hotes, From Harris . 3 . .
Plum Curculio : 7 : . :
Strawberry Weevil. Ridvaion fun Riley : * : ‘
Peach injured by Curculio 7 . : : F :
Mexican Cotton Boll Weevil . * “ é 7 : : 2
Infested Cotton Square . ‘ - : Fs : : : .
Cherry Sawfly : 3 s F s : . . P
Willow Sawfly Larva . S < F ‘ :
Head of Aphis. Redrawn from Siinserland 7 , at: Se
Bucket Pump . :

A Simple Spraying Outfit. Ralicon ion Marlatt .

Powder Gun . 5 . 3 5 . . : ‘
Tiger Beetles. From Partie ‘ - é

Ground Beetles. From Harris . < ‘ . -
Tiger Beetle Larva. From Harris < 3 ‘e : ri .
Ladybird Beetle and Pupa. From Harris . : : - s
Blister Beetle. From Harris “ . 3 : : . .
Soldier-bug . . . . a ‘ 3 . . .
Robber Fly. From Harris . : . 3 . é 5 ;
Syrphus Fly . . - . ‘ - : a : -
White-faced Hornet. From Packard . ‘: 2 : . .
Dragon-fly . 3 . 7 . z . is . :
Egg Mass of Mantis 7 ‘ . 7 s . . : -
Dragon-fly. From Harris . : . . . : . .
Ichneumon Fly ovipositing in Cocoon . 7 * é - ;

Long-tailed Ichneumon Fly. From Harris - ‘ : :
Ichneumon Fly and Chrysalis. Photography by A. H. Verrill .

Ichneumon Flies. from Harris . : - ‘ : -
Cocoons of Microgaster Flies. From Hovis : 3 . 7
Caterpillar with Cocoons of Parasites . . . :
Parasite of Grain Aphis. Redrawn from Wastharx ‘ - 3
Chalcid Parasite of Gypsy Moth’s Eggs. After Howard

Pelecinus Fly 5 3

Tachinid of Army Worm. Dri On oe Plolaradh by ‘Stingeriand
Tachinid Parasite of Gypsy Moth. After Fiske . S .

Cherry Blossoms . s , r é . s . :

x LIST OF ILLUSTRATIONS

Structure of Cherry Blossom . ‘ 2 : : 2 . 7 ‘
Pollination and Fertilization . F . . . .
Cucumber Flowers. d/ter sa By Jamis Hall . . . .
Strawberry Blossoms. ‘ : s . F
Pear Blossoms . . . . a c . . z

Leg of Bumblebee . : . s : Z
Bumblebee. Photograph by A H. “Verrill . 5 .

Easter Lily . F . . : :

Pear Leaf Blight. Retircior fim ‘Galloway. 2 wa
Mushroom. c e . s - . . : ane pee s
Mushroom Spawn. Drawn from Photograph by Atkinson : :
Mycelium of Mold. eadrawn from Zopf . : : : - 7

A Dying Mushroom . . . . -
Potato Leaffaffected with Late Blight. After Galloway

Spores on Leaf. A ‘ : a . ‘ : : .
Smut Sporidia ‘ 3 é a . 5 . P : F
Oats Smut. . : . ‘ . ‘
Corn Smut. Drawn fron Phowograph by Selby ‘ .

Spore Germinating: seen from Above. Redrawn from k, E. Smith
Spore Germinating: seen from Side. Redrawn from Rk. E. Smith
Black Knot on Wild Cherry . : . ‘ é , .

Apple Scab . - . 7 .

Apples dwarfed by Scab. ene ion Chee 2

Apples affected by Bitter Rot. From Scott, U.S S. Department mA Agri

culture . . . * < . .
‘Brown Rot Spores Developing . z i 1 2 a .
Brown Rot Spores Germinating : ‘ 2 . . .
Potato Leaf affected by Early Blight. After Galloway . . .

‘Bee’s Claw with Blight Bacteria. sa Whetzel and Stewart.
Fly with Fungus : .

Soy Bean Root showing ‘Taberdles, Basi Rijbine . 5
Red Clover: Effect of Bacteria. Drawn from Photograph is Hopkins

The White-throated Sparrow. After Biological Survey Z -
‘Tent Caterpillar Nest attacked by Birds . a 8

May Beetle. From Harris .
Click Beetles. From Harris

Meadow Grasshopper. From Harris . . .

Screech Owl. Photograph from Life. - :
Prairie Dog Burrow: Sectional View. After Merriam.

Field or Meadow Mouse. After Samuels. .

Wild ee glory Roots. Drawn from Photograph By Lantz

PAGE
195
195
196
198
198
202
205
209
214
215
216
217
218
220
221
226
227
228
232
232
243
245
246

247
248
248
255
260
273
277
279
284
287
291
292
293
204
306
312
314

LIST OF ILLUSTRATIONS

Hyacinth Bulbs eaten by Pine Mice. Photograph yee Lantz
White-footed or Deer Mouse. After Samuels 5
Cornstalk ruined by Brown Rats. Photograph from Lantz .

Rat Trap used in Burma. A/ter Lantz . . . .
Barrel Trap for Rats. <A/fter Lantz 5 s ‘ . 3
Wellhouse Rabbit Trap. <Afer Lantz. . : .

Georgia Gopher. After Biological Survey . . : F

PART I

FRIENDS AND FOES AMONG THE
WEEDS

COVER DESIGN FOR A BOOKLET ON WEEDS

THE BOOKLET ON WEEDS

Every pupil should make a booklet for each of the important subjects
taken up for study. The booklet should be composed of such drawings
and language work as is done in connection with the study as well as
mounted leaves or other specimens that are readily included in it.

The ordinary plain paper used for drawings serves very well. A good
size is six by nine inches. Three holes should be punched near one end for
binding with raffia in a cover of thicker paper.

It is very easy to get material for the booklet on weeds. Characteristic
leaves, branches, and flowers may be pressed and mounted. Young seed-
lings also may be preserved.

FARM FRIENDS AND FARM FOES

CHAPTER I

The Weeds of Roadsides and Waste Places

One of the commonest sources of the seeding of culti-
vated lands is from the weeds that grow in such abun-
dance along roadsides and on neglected ground. A great
variety of weedy plants are to be found in these situa-
tions, and very often the weeds that first infest tillable
fields come from the seeds of these plants. Consequently
our study of weeds may well begin with these wayside
plants.

When a plant is common and widely distributed, one
is pretty certain to find that it is splendidly equipped for
the battle of life. The Dandelion is a good example of
such a plant. The root is thick and tough and leathery,
running straight down into the ground with branches
toward the bottom. It is filled with a milky juice and is
intensely bitter to the taste. The thickened root enables
the plant to store up food one season for the sending
up of blossoms the next. The tough and leathery struc-
ture enables it to bear trampling by cattle without injury.
The bitter taste and milky juice protect it from being eaten
by insects or higher animals.

The stem between the root and the leaves is so short
that there is practically none at all. This also saves the
plant from injury when it is trodden under foot. The

3

4 FARM FRIENDS AND FARM FOES

leaves are spread out in a rosette; the lower ones are
the longest; the margins are deeply cut; they are bitter
and filled with a milky juice. The rosette habit, the
longer lower leaves, and the incised margins all help the
plant to get the most benefit possible from the sunlight;
while the bitter taste and milky juice render the leaves
unfit for animal food.

The Dandelion flowers are borne on hollow cylindrical
stalks filled with a similar bitter juice and covered with a
woolly coating. By means of the hollow cylinder the
greatest strength is obtained in proportion to the amount
of material used, while the woolly coating makes the
ascent of ants and other wingless creatures difficult.
Sevéral rows of green straplike bracts surround the
flower head, forming what the botanists call the involucre.
With the help of these bracts the flowers close at night.
and in rainy weather. This saves the pollen from being
washed away by the rain, and probably helps the plant
by preventing radiation of heat. A large number of
little flowers are crowded together to make up what we
call the blossom, thus rendering it so conspicuous that it
is freely visited by bees, which carry the pollen from
flower to flower and thus bring about cross-pollination.

When the little ovules have been fertilized by pollen,
the Dandelion closes up for a time in order to ripen its
seeds. Then the flower stem lengthens rapidly, generally
carrying the closed head above the surrounding grass.
When the seed ripens, the bracts open and the round
“Dblowball” appears, ready for the wind to carry the
seedlike akenes away.

It is not strange that a plant with these advantages
should become a weed, crowding out others, and claiming
all the space and light and moisture wherever a few Dande-

WEEDS OF ROADSIDES AND WASTE PLACES 5

lions become established. To a greater or less extent,
practically all the other weeds have similar advantages,
and one of the interesting things about the study of each
is to find out what these advantages
are. This will often point the way
to the best means of checking the
increase of the plant. '

-The Dandelion also illustrates an-
other general truth, namely, that the
way in which we think of a plant
depends upon our point of view. To
farmers and to the owners of lawns,
the Dandelion is a weedy pest, fit
only to be exterminated. To gar-
deners, it is a profitable crop plant,
worthy to be carefully cultivated.
To physicians, it is a storehouse of
remedies for human ills. To bota-
nists, it is a species of great interest because of its adapta-
tions to the conditions of plant life. To artists and poets
and many other lovers of nature, it is of inestimable value
in decorating the landscape and lighting up the fields with
its wonderful disks of gold.

DANDELIONS

SUNFLOWER FAMILY

The Dandelion is a typical example of the great group
of plants called the Sunflower family, or Composite. The
principal character of this group is the association of many
tiny florets ina flower head. A large proportion of our
weeds belong to this family, the members of which have
many advantages in the struggle for existence.

The various adaptations for the dispersal of the seeds are
among the important advantages of the composite plants.

6 FARM FRIENDS AND FARM FOES

The seedlike fruits of some are furnished with a fringe or
tuft of hairs that enables them to becarried long distances by
the wind. The dandelions, thistles, goldenrods, and asters
are examples of these. Many others are provided with
some device for becoming attached to animals. Burdocks,
clotburs and Spanish needles are examples of these.
Still others have hard nutlike fruits that are able to float
upon running water. The tall ragweeds and the common
ragweeds are examples of these.

It is easy to understand why the roadsides are generally
infested with many of the composite plants whose seed-
like fruits or akenes are blown about by the wind. The
open road furnishes free passage, and the fences along its
borders catch hosts of them as they fly along. So the
goldenrods, asters, thistles, and various sorts of wild lettuce
are familiar roadside weeds. These are mostly native
species that are willing to live and let live, and thus do not
entirely overrun the ground as do such imported pests as
Prickly Lettuce, .a roadside weed which ‘has attracted much
attention during recent years. It apparently was first
noticed in New England about 1868, and it is now found
over a large part of the United. States, being especially
abundant in the Middle West.

Prickly Lettuce, when mature, is from two to six
feet high, with a straight stalk bearing large stemless
leaves, the bases of which: clasp the main stalk. The
flowers are borne in an open panicle on the upper end
of the stalk, each blossom being small, yellow, and
not very conspicuous. The first flowers appear about
midsummer, and others continue to develop until au-
tumn. The leaves and stems have a milky juice which
is doubtless a protection from insect attack, while the
numerous prickles over the surface are likewise a pro-

WEEDS OF ROADSIDES AND WASTE PLACES 7

tection from the attack of herbivorous animals. Many
thousand seeds are commonly produced by a single plant,
and each of these seeds is furnished with a fine pappus,
so that it may be carried long distances by the wind.

This is a difficult weed to keep in check. It occupies
roadsides and waste grounds very quickly, and its seeds
are blown from such situations to cultivated fields. The
growing of hoed crops and repeated mow-
ing of patches where the plant is es-
tablished —thus preventing seeding —
are the most advisable measures of pro-
tection.

Among the composite plants whose
seeds are carried by animals, the Bur-
dock is perhaps the most generally
known. Its coarse leaves and spiny seed
heads are to be found in many neglected
corners. It is a biennial, making a vig-
orous growth of leaves near the ground
during the first season, and storing in
the root a large amount of nourishment for the rapid de-
velopment of the great flower stalk the second season.
The tiny florets are crowded together in composite heads,
having a pinkish color, and surrounded by a mass of bracts
with recurved spiny tips. As the seeds ripen, these spiny
burs become brown and easily break away to be carried by
any animals that may come in contact with them, scattering
the seed as they journey. The plants vary greatly in height
according to the richness of the soil in which they grow.
They are easily pulled up when quite small, but the second
season they must be repeatedly cut off below the soil sur-
face to prevent their blossoming, or else killed by pouring
kerosene or some other suitable liquid upon the crown.

8 FARM FRIENDS AND FARM FOES

BuCKWHEAT AND PLANTAIN FAMILIES

The most familiar members of the Buckwheat family are
the sorrels, docks, and smartweeds. These all have small
flowers and the triangular akenes characteristic of the
family.

Two species of Dock are abundant and widely distrib-
uted weeds. These are the Curled Dock, Sour Dock, or
Yellow Dock, and the Bitter Dock or
Broad-leaved Dock. The former is
easily distinguished by its comparatively
narrow curled leaves. The Curled Dock
is ‘often used for “greens,” but the
Broad-leaved Dock is so bitter that it is
not used for this purpose. Both of these
species are likely to be troublesome in
wet places especially along the roadsides
and fences, and can be eradicated only
by extermination of the roots. These
contain so much stored-up nutriment,
that if the plants are simply pulled up
and left upon the surface of the ground,
the seeds often mature; consequently
it is better to burn the plants or at least
to cut the stalk away from the roots.

On account of the way in which the Broad-leaved Plantain
springs up wherever civilized man appears, the American
Indians used to call it White Man’s Foot. It is the most
abundant representative of the Plantain family, though in
fields of grain and forage crops the Narrow-leaved Plantain
is more troublesome.

The Broad-leaved Plantain is a sturdy, vigorous plant,
well adapted to crowding out others in the struggle for

BROAD-LEAVED\\ DOCK

WEEDS OF ROADSIDES AND WASTE PLACES 9

existence. Its roots are large and fibrous, taking firm hold
upon the soil; the main stem is so short as not to appear
above the ground; the broad flat leaves are borne on the
ends of long stems, forming a rosette on the soil surface,
so that the trampling of animals does not injure them. The
leaves are not palatable to higher animals and are eaten
by very few insects. y

In addition to these advantages the small inconspicuous
flowers are borne closely along the sides of the strong and
flexible stalks, upon which the seeds rapidly develop.
The seeds themselves are provided with a mucilaginous
covering, which when wet adheres to the fur of animals so
that they are likely to be carried in many directions.

The Plantain is especially likely to take possession of
waste corners of the premises, as well as neglected places
along roadsides. In lawns it is a vexatious pest, requiring
constant attention to keep it out. The use of a sharp-
pointed hoe which will cut off the plant below the surface
is an effective remedy. During wet weather, the smaller
seedlings may readily be pulled up by hand.

WEEDS OF OTHER FAMILIES

Three common wayside weeds belong to the Evening
Primrose family — Fireweed or Willow-herb, Evening
Primrose, and Sundrops. The first named often springs
up where a fire has left a lot of ashes for the seeds to
sprout in. It is seldom really troublesome in cultivated
land, although its winged seeds must be scattered every-
where.

The Evening Primrose is one of the most abundant
roadside plants. It is especially likely to take possession
of sloping banks and thrives either in open sunlight or in
partial shade. Under favorable conditions it grows to a

se) FARM FRIENDS AND FARM FOES

height of several feet and produces in its curious capsules
vast numbers of the tiny seeds, which may be blown long
distances by violent winds. It may be suc-
cessfully kept in check by repeated mowings
close to the ground.

The little plant called Sundrops seems like
the Evening Primrose in miniature. It is
often abundant along roadsides, and fre-
quently spreads to adjacent fields, where it is
especially troublesome in broadcasted grain
and forage crops. Thorough tillage in cor, .
‘cabbage, or some other hoed crop is the best
way to rid a field of it.

A great variety of other plants are likely
to appear as more or less noxious weeds along
roadsides. Familiar examples in many of the
states are found in Teasel, Elecampane, and
Butter-and-Eggs. Each of these may occa-
sionally become troublesome in cultivated fields if left un-
molested along the roadsides, but they are comparatively
easy to keep in check by attention at the proper season.

Some common roadside weeds have escaped from culti-
vation. The majority of these are likely to be plants
formerly grown in flower gardens, although most of them
are now displaced by more attractive flowers. Throughout
New England, the pinkish blossoms of Bouncing Bet, or
Soapwort, are likely to be seen along the roadside near
an abandoned homestead. In early times this plant evi-
dently was a garden favorite and it remains along the
roadside, though it seldom becomes really troublesome
-as a weed.

In a similar way, the curious Cypress Spurge, the Day
Lily, and the Live-forever are commonly seen along the

WEEDS: OF ROADSIDES AND WASTE PLACES 11

roadsides, to which they have escaped from gardens.
They are usually present in solid patches, which are to be
cleared away only by thorough digging of all the roots.
As a rule these are not likely to go so far afield or prove
so troublesome as certain of the aromatic herbs that
were formerly cultivated. Of the latter Yarrow, Tansy,
and Caraway are commonly most injurious. The seeds
of these may be scattered by the wind over considerable
areas. Consequently it is very
desirable that the small plants
be destroyed as soon as pos-
sible.

Even some of the plants in
the vegetable garden may at
times escape from cultivation (\_
and becometroublesome. The |
most notable illustrations of |.
this are found in Horse-radish, |
Chicory, and Salsify or Vege-
table Oyster. The first named
reproduces only by vegetative
roots; but Chicory and Salsify
produce seeds that scatter in
all directions, coming up as |
weeds in situations favorable
to growth.

Not all of the plants, how-
ever, which are likely to take ;
possession of neglected bits of ground are to be classed
as wholly noxious. For example the Sweet Clovers are
among the most abundant occupants of such soil, crowding
out other plants and developing a thrifty growth of leaves
and blossoms. The blossoms are a valuable source of

12 FARM FRIENDS AND FARM FOES

nectar for honey bees, and the roots of these clovers im-
prove the condition of the soil by adding to its store of
nitrogen and organic matter. It is doubtful whether in the
case of many bits of waste land occupied by these plants
it is worth while to attempt to exterminate them. When
they grow along alfalfa or other fields in which they are
harmful, however, they should of course be destroyed.

OBSERVATIONS FOR PUPILS

1. Makea list of twelve common roadside weeds in your locality.

2. Make drawings of as many of these as you can to use in your
Booklet on Weeds. For this booklet print an attractive title-page.
Perhaps the one on p. 29 will help you in doing this.

3- Press and mount some of the leaves and flowers of the roadside
weeds to bind up in your booklet.

4. Make a list with this heading at the top of the page :

Roadside Weeds I have seen in Neighboring Fields

5. Find out how the seeds of roadside weeds are scattered. Make
lists with these headings :

Seeds scattered by the Wind
Seeds scattered by Water
Seeds scattered by Animals

6. Always watch for new roadside weeds. When one appears, send
a specimen to your State Experiment Station to learn its name. Here
is.the sort of a letter you should send:

, KANSAS,
September 21, 1911.
EXPERIMENT STATION,
MANHATTAN, KANSAS.

Gentlemen : 1 am sending you by this mail in a package
securely packed a plant I found by the roadside near our
school. Wedo not know its name and we shall be greatly
obliged if you will inform me what it is and whether it is
likely to become a troublesome weed.

Sincerely yours,

James A. SMITH.

CHAPTER II

The Weeds of Meadows and Pastures

THE weeds of meadows and pastures that have been in
sod for many years are likely to be native species that
appear to be trying to bring the fields back to the original
condition of the untilled land. Ina for-
est region, the land will revert to forest ;
in a plains region, it will revert to plains.
- This is the natural result of neglect on
the part of the farmer; nature is claim-
ing her own.

The ways in which these fields are
brought back to the wild condition are
well worth studying. Go to such a neg-
lected pasture and notice how shrubs
and vines spring up along the sides of
fences, where seeds have been blown
by winds or left by birds. Notice how
these spread outward by means of seeds
and rootstocks. See how the untilled, MILKWEED Pops
unfertilized sod is “run out,” and re-
placed by mosses or ferns or other weedy growths, and
how the seeds of Hardhack, Sweet-fern, and other plants
begin to grow inthe moss. Then see how these low bushes
form a suitable shelter for poplars, birches, and other trees
to start, and how these in turn may shade the ground for
the early growth of larger trees.

In the plains regions the plants will be different, but the

13

14 FARM FRIENDS AND FARM FOES

process of encroachment from the neighboring species will
be much the same. In pastures where the native grasses
form the chief forage, a frequent cause of weed invasion
is found in keeping too many animals in the fields. These
feed so closely that the grasses are killed out, and other
plants not eaten by the stock take their places.

On the other hand, many ,meadows have problems of
their own. This is most likely to result from a mixture of
the seeds of some. weed with that of the grass, clover, or
grain, or it may be through the seeds in the fertilizers from
the barn. Sometimes these may be weeds new to the lo-
cality, and it is then very important to exterminate them
before-they scatter seed.

TROUBLESOME GRASSES

A number of grasses more or less valuable for forage
often prove. difficult to eradicate in meadows and pastures
where. they crowd out more valuable sorts. They are
able to displace other plants because they spread by creep-
ing underground rootstocks that take complete possession
of the soil in all directions. One
of the worst of these is the
notorious Witch-grass, Quack-
grass, or Couch-grass. In Jo-
calities where Johnson-grass has
been introduced for forage, this
is likely to prove as troublesome.
Wire-grass or Flat-stemmed
Blue-grass is another species
that is likely to take possession
of light sandy soil.

All these troublesome grasses are likely to be introduced,
either with barnyard fertilizers or with grass and grain

SPRIG OF. JOHNSON-GRASS

WEEDS OF MEADOWS AND PASTURES 15

seeds. In permanent pastures some patches may be kept
down by salting, thus inducing close feeding by sheep or
cattle. In some cases, however, the removal of the turf
or cultivation with a hoed crop becomes necessary.

Most meadow and pasture weeds are troublesome, be-
cause they reduce the product of the land, but the Squirrel-
tail Grass or Tickle-grass is much worse
than these, because it produces festering
sores in the mouths of cattle. Consequently
it-not only reduces the grass and hay crop,
but it renders them of less value for feeding.
This is a widely distributed annual, easily
recognized by its glistening, whitish heads
of barbed awns, each awn an inch or two
in length. It is especially troublesome ‘in
Western meadows and alfalfa fields, being
considered in many regions the most pes-

tiferous weed. The seeds are carried by the Sila
wind, though fortunately they are not dis- ane

tributed in grass seed. Rotation with an
arinual crop, or the pulling and burning of
the plants before the heads appear are the
only effective remedies, and they necessitate
community action for the best results. If

one farmer keeps his meadows free and his f
neighbor does not, there is little benefit to
either.

In California a closely related annual grass from Europe
is troublesome in similar ways. It is called Mouse Barley
or Wild Barley, and is often abundant in sandy pas-
tures.

16 FARM FRIENDS AND FARM FOES

SUNFLOWER FaMILY

Meadows and pastures that have been seeded for a long
time are liable to become infested by a number of vigorous
weeds of the great Sunflower or Thistle family (Composite),
some of which prove exceedingly troublesome unless they
are carefully eradicated on their first appearance. One of
the most conspicuous of these is the Oxeye
Daisy or Whiteweed. In many of the New
England and Middle states whole fields are
whitened by it in early summer. The
blossoms are beautiful, but their beauty is
not likely to be appreciated by the farmer
who sees them take the place of a good
crop of hay. The plant is so distinctive
on account of the character of the blos-
soms, with their large yellow centers sur-
rounded by rays of long white petals, that
it is at once recognized by every one. The
flowers are borne on stems one to two feet
high, several of the stems generally devel-
oping from a single root.

CONE-PLOWER It is easy to.see why the Oxeye Daisy
is a dangerous intruder in meadow lands. Its period of
blossoming extends from May to November, so that it is
able to ripen an enormous number of seeds. These are
readily scattered and soon develop into little plants that
are rarely noticed the first season. They blossom quickly
the second season, and continue as perennials thereafter.
Each plant spreads out to form new crowns, and thus crowds
out the surrounding grasses. The fresh leaves, stems, and
flowers are distasteful to cattle, and very few insects will
eat any part of the plant.

WEEDS OF MEADOWS AND PASTURES 17

The careful pulling of these daisies in meadows or pas-
tures when they first appear and before they have gone to
seed, will help greatly in keeping them out. In general,
frequent rotation of crops with good cultivation and fer-
tilization is useful in preventing the growth of this as well
as of other weeds.

The Orange Hawkweed is another dangerous weed of
this family introduced from Europe. Although the date
of its appearance on American soil is comparatively recent,
it has spread over a large part of the country, and in
many places has already become seriously troublesome.
It has a dozen or more medium-sized orange-colored ”
blossoms borne on the top of a hairy stem, a foot or more
high. Nearly all the oblong leaves are in a rosette at the
base of the flower stalk; they are hairy and about four
inches long. The plant lives from year to year by means
of its rootstocks and runners that spread from a single
root in all directions.

The Orange Hawkweed is most likely to appear in pas-
tures or meadow lands, and should be destroyed by a thick
layer of salt as soon as noticed. When large areas are in-
fested, the application of salt at the rate of a ton to the
acre is recommended.

The spiny leaves, stems, and purple flower heads of the
common Pasture Thistle are familiar to every one. This
plant is a biennial. When one of the winged seeds lodges
in a bit of soil, it develops the first season into a rosette of
leaves that store up nutriment in the thickened taproot.
This rosette lives through the winter and the next season
sends up the spiny flower stalk to develop a new crop
of seeds. Fortunately the plant spreads only through the
seeds and is easily destroyed by cutting off below the
“crown.

18 FARM FRIENDS AND FARM FOES

The Canada Thistle is distinguished from the common
pasture thistle by its small flower heads. The plant, as a
whole, is more slender, while its leaves are narrower and

more deeply cut. The flowers are purple,

$a, Fe and are followed by seeds bearing a feath-
OY LF ery pappus. The species is regarded as one
of the most troublesome weeds, largely on
account of its perennial roots which spread
in a]l directions, so that a single plant may
become a center from which many others
develop. Because of these roots, also, the
plant is difficult to. eradicate. Thorough
plowing, repeated mowing,

CANADA seeding downto get a heavy

THISTLE fy

# sod, and the application of

!
Ses.
Ny

y

kerosene to the roots are
the remedies most gener-
ally recommended.

When tillable land is
badly infested with Canada
Thistles the following pro-
cedure is recommended by
the Illinois Experiment Station :—

1. Cut the thistles when in full bloom (July) as close to
the ground as possible.

2. Plow about three inches deep and sow millet or
“Hungarian grass, seeding heavily; harrow. This
may follow the preceding at once or after some
two weeks’ delay.

3. In September plow under the crop, or save it for hay,
as desired. At all events, plow and seed liberally
with rye.

WEEDS OF MEADOWS AND PASTURES IQ.

4. Plow under rye in May and seed again with millet,
or Hungarian grass, or plant to some hoed crop
(corn) and give the most thorough. cultivation,
with continued destruction of every remaining
thistle.

5. Continue the clean cultivation and sharp lookout for
thistles another year.

The Cone-flower, the Flea-banes or White-tops and the
various sorts of Wild Sunflowers are well-known plants
that are frequently troublesome in meadows and pastures.
They generally make a tall and vigorous growth that
shades the grass beneath, and thus prevents its develop-
ment. When they take possession, tillage and reseeding
are necessary.

The Chondrilla, a curious European plant compara-
tively recently introduced, proves troublesome in pastures
with light soils. It is a biennial, developing during the
first season low-lying rosettes of leaves, very similar to
those of the dandelion. On these the small yellow com-
posite flowers appear, to develop later into seed fruits,
which also are strikingly like those of the dandelion. They
are scattered by the wind, so that when once introduced
into a new locality the Chondrilla is likely soon to be gen-
erally distributed. Cultivation and fertilization seem to be
the best measures to exterminate it.

Several trouble makers in lowland pastures are those
weedy composite plants having spiny or hooked fruits that
become attached to the wool of sheep or the hair of other
animals. The Spanish Needles, Bur Marigolds, Beggar
Ticks, and Stick-tights are examples of these. Such plants
are likely to develop in undrained areas, and proper drain-
age is generally necessary to check their increase. Along

20 FARM FRIENDS AND FARM FOES

the margins of streams frequent mowing through the sea-
son will prove helpful.

The Blue.and the White Vervains or Wild Verbenas,
Ironweed, Joe-pye weed, and the various Wild Asters are
other well-known plants of this family that are likely to be
abundant in moist places in pasturesand meadows. Drain-
age, tillage, and seeding down are the best ways to be rid
of them.

CARROT FAMILY

The Wild Carrot, which is typical of the great family of
umbel-bearing plants, is particularly troublesome in pastures
and meadows. Such fields are often wholly occupied by
it, rendering the little grass that may. develop practically
worthless. This plant has been troublesome in the Eastern
states for many years, and has recently been spreading
through the fertile fields of the Middle West.

The small white flowers of the Wild Carrot are crowded
together in flat conspicuous heads, commonly having a
little purple flower in the middle. These develop into
curious masses, suggesting miniature birds’ nests, rounded
in outline. The individual “seeds” are really spinose
akenes which may be distributed by animals or by the wind
that blows the whole seed head along when it breaks off.

‘The Wild Carrot propagates only by means of seeds, so
that the main point to be attained in suppressing it is the
prevention of seeding. This may be accomplished by per-
sistent mowing, which will finally lead to the death of the
plants. At first, mowing simply causes new flower-bear-
ing shoots to be sent out. The plants may also be de-
stroyed by hand pulling, or by cutting them off slightly
below the soil surface with a spud, hoe, or disk harrow.
When a grass field is badly infested with this weed, the

WEEDS OF MEADOWS AND PASTURES 21

best way of treating it generally is to plow and plant with
cultivated crops for a time.

In the states bordering on the Gulf of Mexico another
species of Wild Carrot is very troublesome. It is called
the Small Carrot. It is a biennial, occurring in all sorts
of situations to which the seeds may be carried by wind or
animals.

OTHER HERBACEOUS WEEDS

Two members of the Plantain family are often trouble-
some in meadows and pastures. ‘The Western or Large-
bracted Plantain ap-
pears to have been
originally native to
the Mississippi Val-
ley, but has recently
become very gener-
ally distributed in
grass and clover
seed. It is com-
monly classed as
a winter annual,
though it may also
develop from seeds
scattered in spring.
It differs from the
other plantains in |
its plume-like flower |
heads, due toa large |
bract projecting © MILKWEED SEEDS
from beneath each
tiny floret on the spike. The leaves are short and narrow
so that the plants do not become conspicuous until the

22 FARM FRIENDS AND FARM FOES

flower heads appear. A single plant may produce three
thousand seeds which are likely to be carried but a short
distance. Consequently a dense colony will soon be pres-
ent, crowding out all other vegetation. Pulling the plants,
frequent mowing, or tillage in a hoed crop seem to be the
only remedial methods. The sowing of pure grass and
clover seed is the most important preventive measure.

The Ribwort, Rib-grass, or Narrow-leaved Plantain is one
of the most trying pests that infest light soils. It is com-
monly introduced in clover and grass seed and soon de-
velops a thickened rootstock that renders it very difficult
to eradicate. On account of this rootstock it is a peren-
nial, so that ‘the mere prevention of seeding will not lead
to extermination; the roots must be pulled up, cut off
deeply, or plowed under.

On barren sandy lands
in meadows and pastures
as well as in cultivated
fields, the Sheep Sorrel or
Field Sorrel is likely to take
complete possession of the
_ soil. This well-known weed
_is an indication of poor
_ farming, and the best way
to eradicate it is to enrich
and till the infested areas.
Its seed is very commonly
distributed in barnyard fer-
e tilizers, as well as in other
Siepiisewanr ways, and the plant is likely

to appear in any neglected
spot where the soil is acid. It is so easily eradicated

‘by good methods of farming that it need never become

WEEDS ‘OF MEADOWS AND PASTURES 23

troublesome. Its presence indicates that lime should be
applied.

Another group of plants that are likely to run out the
grass in light soils in dry situations is that of the Five-
fingers or Cinquefoils of the great Rose family. The Com-
mon Cinquefoil, the Silvery Cinquefoil, and the Norwegian
Cinquefoil are the most abundant species. The Barren
Strawberry is closely associated with these in structure and
habit of growth, and is often found in the same situations.
The Cinquefoils have compound leaves composed of five
leaflets, while the leaves of the Barren Strawberry are com-
posed of but three leaflets. Like the common Wild Straw-
berry all these plants occupy increasing areas by send-
ing out runners just above the surface of the ground, the
runners starting new plants that take root and in turn
send out other runners. In this way the soil is soon
covered with a mat of plants that prevents the growth of
grasses.

These low-growing weedy plants often furnish favorable
conditions of shade and moisture for the starting of larger
species like the St. Johnsworts and the Goldenrods. There
are various kinds of each of these, some of which often
render hilly pastures yellow with their bloom. Along with
them are likely to occur the white blossoms of the Yarrow
and the small flower heads of the Wild Asters.

The presence of most of these weeds in light soils is an
indication of the need of soil improvement by tillage and
fertilization.

Various kinds of Milkweeds, especially the Common
Milkweed, are likely to prove troublesomein pastures and
meadows. Such plants send out underground rootstocks
in all directions ; from these, vigorous new shoots come up
so that a strong colony is soon spreading outward to shade

24 FARM FRIENDS AND FARM’ FOES

and destroy the grass. The winged seeds are scattered
everywhere; consequently it is very desirable to extermi-
nate wayside plants. .

Several species of Buttercups abound in lowland meadows
and pastures. When green some of the more abundant of
these have an acrid taste that leads cattle to pass them by,
though this bitterness is so lost in drying that the hay is
not especially injured.

_FERNS OUT OF PLACE

In the more northern regions of our land various species

of ferns often take possession of parts of meadows and

pastures. They are likely to start

along a hedge, fence, or the borders

of the woods, and gradually to ex-

tend over a greater area. The

Brake Fern, or Bracken, is one of

the most abundant of these. It is

especially liable to overrun com-

paratively dry land in the open

HARDHACK| Sunshine, while most of the other

ferns are more likely to overrun

& moist or shaded parts of a field.

ated The Sensitive Fern, the Cinnamon

CAPSULE | Fern, and the Flowering or Inter-

Side View rupted Fern are often troublesome

y in undrained spots. All these

ferns, however, are symptoms of

lack of drainage or neglect of til-

lage, and are to be subdued by im-

proved agricultural methods. Their destruction when they

have full possession of the soil is a difficult matter, requir-
ing frequent hoeing and cultivating for several seasons.

WEEDS OF MEADOWS AND PASTURES 25

TROUBLESOME TREES AND SHRUBS

Over a great central region in the United States the
Sassafras is a troublesome fence-side bush. Its seeds are
carried by birds, and its underground rootstocks spread out
to form a thicket of new plants. In the latter respect, it
resembles the Yellow or Black Locust, though the seeds
of this trée are scattered by the wind. When Locust
thickets are once established in a pasture or meadow, they

‘are difficult to eradicate. Their presence, however, is not

so dangerous as that of the Honey Locust, for the great
thorns of this tree sometimes penetrate the feet of cattle
and cause much trouble.

Many other trees and shrubs are liable to prove trouble-
some in pastures and meadows if permitted to .establish
themselves along walls and fences. The surest way to
prevent their spreading is to cut them off as fast as they
appear, cutting persistently every year, especially in sum-
mer when the new growth is finished. It is, of course, de-
sirable to do away with all needless fences.

Many kinds of shrubs and trees are likely to take posses-
sion of neglected pastures, especially in hilly regions.
In northern localities the Gray Birch and the Aspen
Poplar spring up in great abundance, as do also the Low
Juniper and the Red Cedar or Savin. The latter are
especially likely to arise in clumps of Sweet-fern or Hard-
hack. These are two of the most troublesome pasture
shrubs. The easiest way to keep a permanent pasture free
from such intruders is to exterminate them as fast as they
appear, before they have obtained a firm foothold.

Poisonous PASTURE WEEDS

The most vexatious meadow and pasture weeds are those
that not only prevent the growth of grasses, but are

26 FARM FRIENDS AND FARM FOES

poisonous to stock when eaten. Several such pests have
proved very troublesome in the United States, especially
in the West, although they are by no means restricted to
any one region.

The Loco Weeds are.the most notorious of the stock-
poisoning herbs; they are so-called because the affected
animals become “locoed,” the Spanish word for crazy.
Several species are known, all belonging to the genus
Astragalus, of the great family of Legumes or pod-bearing
plants. Peas, beans, and vetches are familiar examples of
the legume family. Two species of Loco Weeds are the
most important: one is called the Woolly Loco Weed ;
the other the Stemless Loco Weed. Both are sometimes
called Crazy Weed.

The Woolly Loco Weed is a perennial plant having a
general resemblance to a Vetch or
Larkspur. Its leaves and stems
are covered with silky hairs that
give it a silvery effect, and its pur-
ple flowers develop into two-celled
i, seed-pods. Leafstalks and flower
stalks arise from a short central
stem. The plant belongs origi-
nally to a wide area in the Great
Plains region, between Wyoming
and Texas, though especially
troublesome in Colorado, Nebraska,
and Kansas. In Colorado, it was
so destructive that bounties were
offered for its destruction. In
four years nearly $200,000 was
paid by the state for this purpose.
The Stemless Loco Weed has a more slender appearance

POISON HEMLOCK

WEEDS OF MEADOWS AND PASTURES 27

than the Woolly species. Its leaflets are more slender and
its pods are one-celled. It is distributed over an even
greater area than the Woolly Loco Weed.

The Larkspurs are closely related to the Loco Weeds,
belonging to the same family of Legumes. There are
many species of these, several of which are known to be
poisonous to stock. The Dwarf Larkspur, the Purple
Larkspur, and the Wyoming Larkspur are the most trouble-
some kinds. They are especially likely to be eaten in early
spring, when the leaves offer tempting forage to cattle, be-
fore the better plants are well started.

Another weed that has been very troublesome in poison-
ing stock is the Rattlebox or Rattleweed. This is native
to a great region extending from New Jersey to Kansas
and Minnesota, occurring especially in low sandy soils. It
is dangerous to horses and cattle, both in the pastures and
in hay. In some of the Western states disease in horses
caused by it is called the Bottom Disease, because only
stock pasturing on the so-called bottom lands are likely to
be affected by it.

A few poisonous weeds commonly occur in wet places in
meadows and pastures. Thus the well-known Sneezeweed
withits attractive yellow flowers is poisonous to cattle, sheep,
and horses. It is abundant along ditches and the borders
of ponds and streams. The Poison Hemlock or Spotted
Cowbane, which occurs in similar situations, is even more
dangerous. Not only are all parts of the plant extremely
poisonous to man and animals, but water in which the
roots have been trampled may prove poisonous. The
roots have an aromatic taste that leads children to eat
them, sometimes with fatal results. Both these plants
should be exterminated wherever they occur.

1 In the case of all these poisonous weeds the only safety

28 _FARM FRIENDS AND FARM FOES

lies in exterminating them to as great an extent as possible.
And it is especially important that there be codperation to
this end among all the landowners of a locality.

Poisonous TREES AND SHRUBS

The Choke Cherry is one of the commonest and most
dangerous of shrubs. It is found along roadsides, woods
and fences, throughout the greater part of Canada and the
United States. Its seeds are
scattered everywhere by birds,
and it spreads rapidly by un-
derground stems. As the leaves
wilt after the bushes are cut,
Prussic acid, a virulent poison,
is formed within them by the
combination of two nonpoison-
ous substances. This is often
fatal to cattle that feed upon
the withering branches. Conse-
quently it is desirable to prevent the growth of Choke
Cherry bushes, and to leave no freshly cut leaf-bearing
branches within the reach of stock.

Black Cherry leaves also develop: this poison as they
wither, and perhaps the same is true of other wild cherries.

Certain species-of Laurel, especially the Mountain Laurel
and Sheep Laurel or Lamb-kill, are poisonous to stock.
The leaves and green stems contain a principle that is even
more fatal than strychnine.

Among the more important shrubs that are likely to
spread from walls and fences into the adjacent fields are
the various species of Sumachs. The seeds of these are
left along fences by birds, and the resulting plants, when

WEEDS OF MEADOWS AND PASTURES 29

well grown, send out rootstocks in all directions. From
these rootstocks other plants arise, so that a continually
expanding thicket of shrubbery is soon established. The
Smooth, the Dwarf or Mountain, and the Staghorn or Vel-
vet Sumachs, are the common nonpoisonous species. The
Poison Ivy and the Poison Sumach or Poison Dogwood are
.the poisonous species. The Poison Ivy is one of the most
generally distributed. These, however, are harmful chiefly
to mankind and are external irritants rather than internal
poisons.

A LITTLE BOOK

PROFITLESS WEEDS

BY

CHARLES R. JONES

Tough thistle choked the fields and killed the corn,
And an unthrifty crop of weeds was borne.
— Drypen.

ILLUSTRATED

THE BROWN SCHOOL

Igo

A SUGGESTION For TITLE-PAGE OF BOOKLET ON WEEDS

30 FARM FRIENDS AND FARM FOES

OBSERVATIONS FOR PUPILS

PasTURE WEEDS

1. Make a list of twelve weedy plants that you have seen growing in
the pastures of your locality.

2. Are such plants more troublesome along fences, hedges, or walls,
than in the open pasture ?

3. Are weeds more abundant in pastures heavily stocked with domes-
tic animals or those lightly stocked ?

4. What are the best ways of getting rid of pasture weeds in your
vicinity ?

5. Ifa weedy pasture is near, make @ list of the weeds present and
mention the way in which each kind probably got started in that field.

6. How often are pastures plowed up and reseeded in your locality ?

MEADOW WEEDS

1. Make a list of the ten most troublesome weeds present in the
meadows of your locality.

2. See if you can tell which ones were probably started by being
mixed with grass, grain, or clover seed; which were blown in by the
wind; and which were brought in in other ways.

3. Are any of these plants that have been recently introduced into
your region ?

4. If ameadow.is near, make a list of the weeds present and mention
the way in which each kind probably got started in that field.

5. How often are meadows plowed up and reseeded in your locality ?

6. Which meadows show the most weeds, those recently seeded
down or those that have been seeded down for a long time ?

ReaD such references in the following as your teacher directs : —

Some Poisonous Plants of the Northern Stock Ranges, Farmers’ Bulletin 206,
Thirty Poisonous Plants, Farmers’ Bulletin 86. Johnson-grass, Farmers’ Bulletin
279. Canada Thistle, Circular 27, Division of Botany, U. S. Dept. Agr.

CHAPTER III

The Weeds of Gardens and Cultivated Fields

THE weeds that infest gardens and cultivated fields are
familiar to most people. Such plants are seen daily by
every one in town and country, and must be constantly
kept in mind by all farmers and gardeners. To a large
extent they are annuals and produce seed in such abundance
that neglected soil is quickly covered with young plants.
Most of them are easily kept in check when the ground is
given proper tillage.

Grass FAMILY

By far the most troublesome of these garden weeds is
the Quack-grass or Witch-grass, which is known by a dozen
other names. This notorious pest multiplies both by seeds
and by underground rootstocks
that penetrate the soil in all direc-
tions, sending up leafy branches
everywhere. If these rootstocks
are cut into pieces, each piece
will produce a new plant. On
this account, hoeing and culti-
vating ground infested by Witch-
grass is likely to do more harm than good. When the
grass has taken complete possession of a piece of land, it is
often cut for hay, but this only leads to the wider scatter-
ing of the seeds through the fertilizers from the barn.

Quack-grass thrives upon ordinary tillage, and is to be
subdued only by a vigorous and persistent course of treat-

gr

QUACK GRASS

32 FARM FRIENDS AND FARM FOES

ment. It is often said that to kill it, you must dig it out,

dry it on a rock, burn it, and then be very careful where

you put the ashes! In gardens and limited areas, the best

way is to dig out the rootstocks, when no crop is in the

ground, with atined potato digger and cart them away.
By keeping persistently at the
roots every spring and fall, the
land can finally be cleared. Small
patches may also be smothered by
covering the surface with boards,
tarred roofing paper, or something
similar.

Several species of annual grasses
are likely to become troublesome
in gardens and fields during the

PIGEON . .
GRASS latter part of the growing season.
One of these is the curious Fly-
away-grass or Old-witch-grass, the
plume-like seed heads of which
are to be seen every autumn roll-
ing before the wind, and finally
lodging along fences. Because of these heads that thus
fly along the surface of the ground, dropping their seeds
as they go, this grass is likely to appear even in ground
that has been kept free from seeding plants. Consequently
it is desirable that the grass be kept in check wherever
it appears.

Two species of Foxtail or Pigeon-grass are universal
weeds. The Yellow Foxtail or Common Pigeon-grass
seems to be generally more abundant than the Green Fox-
tail or Bottle-grass. They are very similar, except for the
difference in color. Both appear about midsummer in
gardens, cultivated fields, and waste places, often carpet-

It

WEEDS OF GARDENS AND FIELDS 33

ing the ground with their spiked heads. When mowed off,
they send up new heads, which are able to develop close to
the soil surface. The seeds of the Foxtails are commonly
distributed in clover and millet seed, and so
are often sown with these. Persistent late
culture and hand weeding are the only effi-
cient means of checking these grasses.

One or more kinds of Crab-grass or ©
Finger-grass are very likely to develop after
midsummer, especially in wet seasons or on
moist land. These have the peculiarity of
spreading their stems in all directions, the
stems striking roots into the soil whenever
in close contact with it. This makes the
plant difficult to eradicate, because any of
the rooted stems left will continue to grow.
Fortunately it is an annual and so does not retain posses-
sion from season to season. It is likely to develop in
neglected barnyards and thus have the seeds scattered with
the fertilizers.

The seeds of the Barnyard Grass are also very likely to
be scattered in the way just mentioned. This isa tall coarse
plant, often reaching a height of three or four feet. It
frequently develops in corn and potato fields late in summer,
getting its growth after cultivation ceases. It is compara-
tively easy to subdue by hand pulling. Under the name
Japanese Millet it has lately been added to the list of de-
sirable forage plants.

} y
ts FRUIT

SHEPHERDS PURSE

MustTarp FAMILy

Several abundant garden weeds belong to the Mustard
family. Wild Mustard or Charlock, Black Mustard, Wild
Radish, and Peppergrass are familiar illustrations. These

34 FARM FRIENDS AND FARM FOES

are all found in gardens more or less, though the Mustards
are more likely to be troublesome to grain and forage
crops.

The Shepherd’s Purse is one of the garden weeds most
likely to develop early in the season. It is able to do this
because it is a winter annual, developing the autumn be-
fore into a rosette of low-lying leaves. In spring it sends
up its slender central stalk, along the lower and middle
parts of which are a few narrow leaves, some having curi-
ously incised margins, while along the upper part are the
small white flowers, crowded together toward the top.
These develop into the purse-shaped seed pods, borne on
the ends of slender stems.

This familiar plant is commonly found wherever a few
inches of waste ground give it an opportunity to grow.
Tillage late in autumn or early in spring is the best way to
destroy it.

Pink Famity

One or more species of Chickweed are so widely distrib-
uted that they occur in almost every garden. The Smooth
Chickweed is known by its smooth leaves and stems, and
its minute white flowers with the green pistils longer than
the petals. It is a winter annual. The Mouse-ear Chick-
weed is known by its hairy leaves. Technically there are
two species known by the latter name; one of these is a
perennial.

These Chickweeds multiply by spreading over the sur-
face of the soil as well as by seeds which are produced in
abundance throughout the season. They are comparatively
easy to keep in check by proper tillage.

During the latter part of summer, the heart of the care-
less gardener is often vexed by the rapid growth of the

WEEDS OF GARDENS AND FIELDS 35

succulent Purslane or “pusley.” Its thick brown stalks
creep along the ground, spreading rapidly from the root,
and seriously interfering with crop growth. The leaves,
as well as the stems, are smooth and thick, while the pale
yellow flowers borne in the axils of the leaves generally open
only in the morning, when the sun is shining. The small
seeds are produced in capsules, the tops of which come off
when the seeds ripen. It has been estimated that 1,250,000
seeds are sometimes produced byasingle plant. Fortunately
this Purslane is an annual, requiring only frequent surface
tillage for its prevention, although when the plants become
large, it is necessary to remove them to prevent their grow-
ing again, This is one of those weeds that compel the gar-
dener to keep a soil mulch through the summer, and thus
conserve the moisture during the driest season of the year.

GOOSEFOOT AND AMARANTH FAMILIES

The plant commonly called Lamb’s Quarters, Goosefoot,
or White Pigweed, is a widespread and troublesome gar-
den pest. Where it finds room, it be-
comes a large and vigorous weed, five
or six feet high and about two feet in
diameter. Usually it is two or three
feet high. The leaves are somewhat
arrow-shaped, with irregular teeth along
the margins, and rather long, slender
petioles. The narrow clusters of green-
ish white flowers appear in the axils
of the leaves, toward the ends of the
branches. The general color of the plant is pale green,
with a whitish powder scattered’ over the flowers and young
growth, and often over the leaves, also. The small seeds
are black and shiny when separated from their greenish

36 FARM FRIENDS AND FARM FOES

covering. They are developed in great numbers, and
often produce plants so crowded together in field and gar-
den that there is no chance for the regular crop to mature.

This White Pigweed often grows rapidly, ‘and should
be destroyed by surface tillage. If it gets started in the
garden, frequent cultivation is the best way to keep it in
check.

The common Pigweed is one of the plants most char-
acteristic of neglected gardens in the latter part of
summer. The broad, wavy-margined leaves are borne on
the ends of long petioles that arise from a cylindrical main
stalk, which in turn grows from ared root. The plant is
sometimes known as Redroot. It is an annual, developing

. rather late in the season, and consequently is very likely
to be found in fields of corn and potatoes after cultivation
ceases. Each plant produces great numbers of small
seeds, some of which may ripen as early as August. The
pest is to be attacked by thorough cultivation, or by hand
pulling in fields where late tillage is impracticable.

As far as its flowers and seeds are concerned, the
Tumbleweed is closely related to the Pigweed, both be-
longing to the Amaranth family; but in its manner of
growth it is very different. The Tumbleweed sends out
numerous branches, that give it a broad expanse, so that
when the main stalk breaks off near the root, it is able to
roll and tumble along the ground with every gust of wind,
scattering its seeds as it goes. It commonly brings up be-
side a fence or other obstruction, where regular windrows
of the plants may sometimes be seen. It is easily kept in
check in gardens and cultivated fields by tillage or hand
pulling. .

WEEDS OF GARDENS AND FIELDS 37

SUNFLOWER FAMILY

The Ragweed or Roman Wormwood is a pestiferous
plant found in most situations where weeds may grow late
in summer. It is nearly always to be seen along paths
and highways, in fence corners, and along garden borders,
as well as in cornfields and wheat stubble. It is an an-
nual, and has a straight central stalk from
which many spreading branchesarise. The
latter bear numerous leaves with deeply
cut lobes and many small, greenish, incon- .
spicuous flowers. As in the case of the
Horseweed, to which the Ragweed is
closely related, the pollen-bearing blossoms
are borne along the sides of the branches.
near the tips, while the seed-bearing flowers
are borne along the lower parts of the
same branches. One reason the Ragweed is so ubiquitous
is because the young plants are able to develop in hard
soil where most weeds cannot get a foothold.

When mowed off an inch or two above the ground, the
Ragweed is likely to produce new branches from the
cut main stalk, from which seeds may develop; conse-
quently thorough work is necessary in subduing the pest.
One effective method is to pasture infested fields with
sheep.

In the Middle West, the Giant Ragweed or Horseweed
is one of the most abundant plants. Its luxuriant growth
is to be found everywhere, but it is especially vigorous and
troublesome on moist bottom lands. Poorly cultivated or
untilled parts of such fields are frequently covered with a
dense growth of this robust annual, the seeds of which
are carried by water from one valley to another. It often

38 FARM FRIENDS AND FARM FOES

reaches a height of ten or twelve feet, the simple stems
shooting straight upward and bearing along their ribbed
sides the large opposite three-lobed leaves with dentate
margins. The flowers are small and inconspicuous, being
borne in rows along the ends of the branches. The staminate
or pollen-bearing blossoms are above the pistillate or seed-
bearing flowers. The former are much more abundant
than the latter. Each of the pistillate flowers bears a
single seed. As the Horseweed is an annual, it may be
kept in check by thorough cultivation, or in untilled lands
by repeated mowings. There is often danger, however,
that during times of floods, bottom lands may be reseeded
from regions upstream.

The Clotbur or Cocklebur-is another pernicious weed of
the Sunflower family, which commonly develops Jate in the
season in gardens and cultivated fields. This plant is eas-
ily known on account of the peculiar burs, or seed’ heads,
covered with. hooked spines. It is a low-growing annual,
attaining a height of. but a foot or two, but
spreading over quite an area. The prin-
cipal stalks are tough and woody, and
bear the broad triangular leaves on the
ends of long, slender petioles. Two sorts
of flowers are borne by each plant, stam-
inate or pollen-bearing, which appear’ at
the upper end of the principal stalk, and
pistillate or seed-bearing, which develop
lower upon the same stalk. The pollen: drops from the
former upon the latter, or is blown from plant to. Pan
by the wind, and: thus fertilizes.the embryo seeds.

The bur really consists of a lot of bracts called, whew thus.
grown together, the involucre. As the seeds mature: the
bur hardens, the hooked spines becoming ' stiffer -as- they:

a
me CLOT BUR

WEEDS OF GARDENS AND FIELDS 39

dry out, until finally they are strong enough to cling to the
hair or fur of any passing animal.

Fortunately the Cocklebur spreads and -multiplies only
through its seeds, so that it is comparatively easy to keep
in check in cultivated fields by means of clean culture con-
tinued late in the season.

Potato FAMILy

The Horse Nettle is a perennial weed native ‘to the
southeastern region of the United States, whence it has
gradually spread westward. Its general resemblance in
leaf, flower, and fruit to the common potato shows its re-
lation to that plant. The two belong to the same genus
—Solanum. The rough, prickly plants attain a height
of from one to two feet, bearing good-sized oak-like downy
leaves, with long spines projecting from the midrib on
both the upper and the lower surfaces. The flowers are
white or purple, and develop into round yellow berries.
The latter are composed of a pulpy substance in which
many small seeds are embedded. These seeds are dis-
tributed by birds.

Besides the seeds, the plant spreads and reproduces by
slender rootstocks that penetrate the soil in all directions
and live from season to season. These make the Horse
Nettle a difficult pest to subdue. Clean cultivation and the
eradication or starving out of the rootstocks are the best
methods.

‘Like the Horse Nettle, the Buffalo Bur is a native of
America, having originally developed upon the plains of
the far West, where its burs became entangled in the hairy
‘fur of the wandering buffaloes. Since the advent of the
white man, the plant has spread eastward, until now it is
found in many regions throughout the country. Like the

40 FARM FRIENDS AND FARM FOES

Horse Nettle, also, this plant belongs to the same genus as
the potato, the flowers resembling those of this common
vegetable in shape, although they are yellow in color. It
is an extremely spiny plant, more so than the Horse Nettle,
and its fruit develops into spinose burs, inside which are
numerous small black seeds. These become attached to
| clothing or the hair of animals, and
are thus disseminated, although the
| whole plant is sometimes blown
from place to place, carrying the
_seeds with it.

The Buffalo Bur may be kept ©
down, if seedingis prevented, either .
by mowing or cultivation.

‘Nearly a score of species of
Ground Cherries, of the genus Phys-
alis, are found in North America.
All are readily recognized by the
curious berry-like fruit inclosed in
the inflated bell-shaped calyx that
forms a pod-like covering. The

GROUND CHERRY OR foliage resembles that of the to-

ee mato. One of the most abundant
sorts is called the Husk Tomato, or Strawberry Tomato,
and is grown as an edible fruit.

These Ground Cherries are readily kept in check in a
well-tilled garden. Most of them are annuals, though at
least one is a perennial.

WEEDS oF OTHER FaMILiEs

Many years ago, perhaps in the days of Pocahontas,
a weedy plant appeared in the gardens of Jamestown,

WEEDS OF GARDENS AND FIELDS 41

Virginia. It was a very distinctive species with good-
sized, dark green leaves, large white flowers, and curiously
spined fruit capsules. It had a decidedly disagreeable
odor, and was found to be very
poisonous. So the plant became
well known, and when it spread
to the gardens of the surrounding
region, it was called Jamestown
Weed, a name that was gradually ae Eopsule

contracted to Jimson Weed, by pr JIMSON WEED

which it is now generally known.

It is also called Thorn Apple, Jamestown Lily, Apple of
Peru, and Mad-apple. Possibly the last name is due to
the fact that infusions of leaves have been used for the
cure of hydrophobia. Or it may be due to the fact that
the plant when eaten produces convulsions and delirium.

In addition to the white-flowering Jimson weed, there is
a very similar purple-flowering species. Both are annuals
from the tropics, and are especially abundant in the South-
ern states. Nearly every year children are poisoned by
eating the seeds. These plants should be destroyed wher-
ever they are seen.

There are several creeping plants that are troublesome
as weeds. One of the worst of these is called the Hedge
Bindweed or Wild Morning Glory. Its rootstock is peren-
nial, while the stem and leaves die down every autumn.
Its leaves are somewhat arrow-shaped, and its white or
purplish flowers bear a general resemblance to those of the
cultivated Morning Glory. It is especially troublesome on
low moist land.

The Wild Morning Glory is propagated both by seeds
and by the spreading of underground roots. On account
ef these roots it is a difficult weed to eradicate. Hoeing

42 FARM FRIENDS AND FARM FOES

and pulling are effective when only a few of the plants
are present.

A similar species is Wild Buckwheat or Black Bindweed.
The stems and blossoms of this plant are smaller than are
those of the Bindweed, while the flowers, instead of being
produced singly on stems, are quite small and clustered to-
gether in racemes. Itis called Wild Buckwheat because its
seeds are quite similar to those of buckwheat. It is an an-
nual species, and consequently is not very difficult to subdue
by cultivation.

A number of. the more abundant weeds are likely to de-
velop in gardens and plowed fields, during the latter part
of summer. In some cases they are really a benefit, in
that they enforce surface tillage during the season when a
soil mulch is most needed. In fields of corn, potatoes, and
some other crops, however, such late tillage is impracti-
cable, and about the only way to fight the weeds is to pull
them up by hand.

OBSERVATIONS FOR PUPILS

1. How many of the weeds treated of in this chapter infest gardens
and cultivated fields in your locality ? Here is the list: —

Barnyard Grass Hedge Bindweed
Black Bindweed Horse Nettle
Buffalo Bur Jimson Weed
Chickweed Lamb’s-quarters
Crab-grass Pigweed
Finger-grass Purslane
Fly-away-grass Quack-grass
Giant Ragweed Ragweed *
Green Foxtail Shepherd's Purse
Ground Cherry Tumbleweed

Yellow Foxtail

2. What other weeds occur in gardens and cultivated fields in your
locality ?

WEEDS OF GARDENS AND FIELDS 43

3. Make a list of the field and garden weeds you are acquainted with,

and print the names in alphabetical order on a page of your booklet.

4. Make a careful study of such of these weeds as your teacher thinks

desirable, incorporating the results into your booklet. The following
outlines may prove helpful for such studies : —

Pe ‘oo

Be Oe

Mm PWN 4

YAW RY vo

PURSLANE

Covnt the number of seeds in one “ pusley” capsule.

Count the number of capsules on one long branch.

Estimate the number of seeds produced by the plant.

Count the number of plants in a space two feet square, and estimate
the number of seeds produced in a square rod.

How are “pusley ” seeds distributed ?

When do you find Purslane most abundant ?

Make a drawing of stem, leaf, and fruit.

LaMB’s QUARTERS. OR WHITE PIGWEED

. Why should this be called White Pigweed ?

. Where have you found it most abundant ?

. How are the seeds scattered ?

. Do you know how it looks when young?

. Have you seen any leaves affected by leaf miners? If so, rear some

of the adult flies from them, and see whether they resemble the flies
you can easily rear from spinach.

. How early should the plants: be destroyed td prevent their maturing

seed?

. Draw a good-sized leaf, showing petiole, veins, and margin.

OUTLINE FOR OTHER WEEDS

What sort of root has this plant ?

Does it spread by underground rootstocks ?

How is it protected from being eaten by animals ?

When do the flowers appear? Describe them.

When do the seeds ripen? How are they scattered ?

Estimate the number of seeds on one plant.

What do the young seedlings look like? When may they be found ?

44 FARM FRIENDS AND FARM FOES

8. In what condition does the plant pass the winter—in the seed
state, or as a living plant, or both ?

g. How is it commonly introduced to new fields ?

1o. In what ways may it be destroyed or prevented from growing ?

11. Make some or all of these drawings : —

Root Flower
Leaf Seed

S|
\ Sete
oe a};

GILL-OVER-THE-GROUND

CHAPTER IV

The Weeds of Grain and Forage Crops

THE weeds that infest fields of grain and forage crops
are commonly introduced with.the seed. In many cases,
however, the weed roots or seeds may be present in. the
soil because of neglect of crops previously grown upon the
land, or the seeds may be scattered through the fields during
autumn, winter, and spring before the grain or forage crop
is sown. Consequently the surest way to prevent injury in
such fields is to sow clean seed and adopt good agricultural
methods.

Grass FAMILy

Perhaps the most notorious grain-field plant is Chess or
Cheat Grass. In earlier days there was much discussion
in regard to the origin of this pernicious plant. The idea
was very commonly upheld that wheat turned to Chess, so
that under certain conditions, as it was supposed, a farmer
might sow good wheat seed and reap only a crop of Chess.
It seems likely that this was the basis for the use of the
common name Cheat. It has long been known, however,
that Chess comes from seed of its own, and not from wheat,
so that when the Chess appears it is certain, either that its
seed was present in the ground before sowing or that it
was mixed in with fertilizers or the wheat that was used
for seeding. It is well established that the seed of Chess
may lie dormant in the soil for several seasons, and this

45

46 FARM FRIENDS AND FARM FOES

probably is the explanation of its presence in many grain
fields, in which no Chess seed developed the previous
season. :

‘Chess is a winter annual, and its slender seeds are some-
what similar to oats, although they are darker in color, and
the grain is of smaller size. These seeds are likely to be
found in cheap qualities of clover, oats, and wheat seed,

Mixture of weed seeds commonly found in low-grade alsike clover seed: a, alsike
clover; 4, white clover; c, red clover; d, yellow trefoil; ¢, Canada thistle;
J, dock; g, sorrel; 2, buckhorn; 2, rat-tail plantain; 2,lamb’s-quarters; Z, shep-
herd’s purse; m, mayweed; z, scentless camomile; 0, white campion; 4, night-
flowering catch-fly; 7, oxeye daisy; 7, small-fruited false flax; s, cinquefoil;
4, two kinds of peppergrass; z, catnip; v, timothy; x, chickweed; y, Canada
bluegrass; z, clover dodder; 7, mouse-ear chickweed; 2, knot-grass; 7, tum-
bling amaranth; 4, rqugh amaranth; 5, heal-all; 6,lady’s thumb. (Enlarged.)

although, as in the case of many other pernicious plants,
the public inspection of seeds is driving these poorer qual-
ities out of the market. When a field is infested with
Chess, it may well be planted to a hoed crop for two or
three seasons. This procedure, and the sowing of pure
seed, will prove an adequate preventive.

WEEDS OF GRAIN AND FORAGE CROPS 47

In the great spring wheat regions of the Northwest, the
Wild Oat is one of the most troublesome weeds in fields of
oats. This plant bears a striking resemblance to the or-
dinary cultivated oats, from which it is easily known by the
long-tipped awns borne by the terminal florets of. each
cluster of flowers, and by the fact.that the kernel or grain
is very light. When present in an oats field, these Wild
Oats mature-earlier than the main crop and in an irregular
fashion, many of the individual florets dropping away as
they ripen. The presence of the plant not only reduces
the regularcrop, but also sometimes causes trouble because
the stiff awns irritate the mouth parts of the. animals: to
which the crop is fed.

The seeds of Wild Oats retain their vitality for a long
period when buried. deeply in the soil. Consequently, a
badly infested: field may require several seasons’ tillage’ in
other crops before. all the seeds present have germinated.
A carefully planned rotation is the best method of. pane
rid of the plant..

MusTArRD FAMILY

.In many localities, the most vexatious weeds in grain
fields are those belonging to the Mustard family. The
seeds of these are very commonly mixed with oats.and other
grains, so-they: are sown at seeding time. One of the most
generally troublesome is the Charlock, Wild Mustard, or
English Mustard, as:it issometimes called. This was origi-
nally a native of Europe, but is now very generally dis-
tributed in America. It is especially troublesome in fields
of oats, the young mustard plants growing along with the
oats: and materially: lessening the crop. Charlock is dis-
tinguished. from--the other Mustards by a pod, long and
knotted,.and having at the tip arather thick, two-edged beak.

(

48 FARM FRIENDS AND FARM FOES

The Black Mustard is a much more prickly plant, having
pods that are more or less oblong, smooth, and four-angled.
A single plant of either of these Mustards may produce
from 10,000 to 15,000 seeds. This accounts for the enormous
numbers of them that often appear in neglected fields.

In many parts of Canada and the United States, the
Tumbling Mustard or Tall Mustard has recently become
a troublesome pest. This species seems to have been in-
troduced with the soil carried as ballast by ships, and dumped
on the so-called ballast grounds at Philadelphia. It has.
since been widely distributed by railroads, and is able to
develop under a great variety of climatic conditions. Like
the other Mustards, this is an annual. It branches freely,
and reaches a height of from two to four feet. The small
yellowish flowers are borne along the tips of the slender
branches, and are less conspicuous than those of the Char-
lock. The seed pods are very slender, and are commonly
two or three inches long. This species is closely related to
the more widely distributed Hedge Mustard, the pod of
which is much shorter and of larger diameter.

In the case of all these Mustards, as with most annual
weeds, careful cultivation with a hoed crop for a series of
years is necessary for-complete exterminationin a field. The
seeds of many of the plants of the Mustard family retain
their vitality for several years, so that those: which are
buried deep in plowing, are likely to be brought to the
surface long after they matured, and find favorable condi-
tions for growth. It is especially important that grain’
used for sowing be free from the seeds of any of these
plants.

Numerous experiments have shown that young mustard
plants may be killed in grain fields without serious injury
to the grain crop by spraying with a solution of one part

WEEDS OF GRAIN AND FORAGE CROPS 49

iron sulphate to four parts water by weight. The applica-
tion should be made on a fair day after the dew has evapo-
rated.

Another member of the Mustard family, which is
troublesome in fields of winter grain, as well as in those of
flax, is the so-called False Flax. This is a pest from
Europe which has been introduced into America compara-
tively recently. Its resemblance to Flax is indicated by its
common name. The flowers and seeds, however, are much
smaller than those of Flax. In appearance and habit of
growth, it also bears a general resemblance to Shepherd’s
Purse and Peppergrass. Like these weeds, it may be
either an annual or a winter annual; that is, the seeds may
germinate in spring and blossom the same season, or they
may germinate in autumn, the plants living through the
winter and blossoming the next season. As a rule, it is
only the latter that mature their seeds, the season in the
Northern states being too short for the seeds of those
plants that germinate in spring to reach maturity.

False Flax is generally introduced as a mixture in flax
seed, clover seed, and various grass seeds ; consequently all
such seeds should be carefully examined before being sown.
When the pest has become established, rotation with a hoed
crop is necessary to exterminate it.

WEEDS OF OTHER FAMILIES

The Cockle or Corn Cockle is a well-known pest in grain
fields. Its presence is generally due to impure seed, the
black seeds of the Cockle being sown with the wheat or
other grain. It is an annual, so that it causes little trouble .
unless sown with the seed. It grows to a height of three ,
or four feet, and has a slender stem with very few branches,
each of which bears on its tip a good-sized reddish-purple

50 FARM FRIENDS AND FARM FOES

blossom. There are comparatively few of the Jong, narrow
leaves, which, with the stem and outer part of the flowers,
are covered with a coat of fine hairs.

The dark purple or blackish seeds are produced in an ob-
long pod. They are threshed with the wheat; and as they
are nearly the size and weight of the wheat kernel, it is
very difficult to separate the Corn Cockle seeds from the
grain. Inconsequence the flour is of inferior quality. The
presence of the seeds is shown by the black particles of the
pulverized seed coat. Flour badly contaminated by Cockle
seeds is injurious when eaten, as they.contain a poisonous
principle that produces disease and death.

The Cockle plants are easily pulled up in wheat fields
and should be removed, especially from all fields that are
intended to produce seed grain.

Few weedy plants have such distinctive beauty as has
the famous Field Poppy or Corn Poppy of the English
poets. In England the fields of wheat are called corn
fields, although in America this term is usually restricted
to Indian Corn. The Field Poppy has long been a pest in
European wheat fields; but it gives to the landscape a
glow of scarlet color, much as our own meadows are
decorated with the Oxeye Daisy. This Field Poppy has
been introduced into many regions in America, probably
through adulterated -seed, and threatens to become trouble-
some wherever it appears. It is so conspicuous a plant
that it can scarcely be overlooked, and when first introduced
into a locality it should be exterminated. This is also one of
the garden Poppies and of course there is danger that it
_may spread to cultivated fields.

The famous Russian Thistle or Russian Tumbleweed is
another European plant that has become destructive in
America. The history of the introduction of this pest has

WEEDS OF GRAIN AND FORAGE CROPS 51

been carefully traced. Apparently it was first brought in
by immigrants from Russia in the great Northwest, about
1873, and since then it has spread with marvelous rapidity,
not only by being blown across long stretches of prairie,
but also by means of railroad trains, and probably -in
other ways. It has attracted more attention than any
other weedy plant of recent introduction, and has been
the cause of a great awakening in regard to the whole
subject.

The Russian Tumbleweed is an annual that starts. as a
slender seedling bearing a general resemblance to a very
young pine tree. Its leaves are slender, soft, and velvety.
It grows rapidly, however, and toward midsummer takes
on a spiny appearance, spreading out to cover an area three
or four feet in diameter, with the height nearly as great,
and a rounded outline similar to that of our common
Tumbleweeds. When the seeds are finally mature and
ready to be dispersed, the main stalk breaks off at the
surface of the ground and the plant rolls away. It then
justifies its German name “ Wind Witch,” or its Russian
name ‘Leap the Fields.” With the impetus given
by a violent wind, the plants go rolling and tumbling
across the prairies, to be caughtin great windrows when an
obstacle interferes. As they roll along they drop their
seeds by the way, so that the country traversed is likely to
become thoroughly infested.

While the greater part of the weeds that infest grain
fields arise from seeds present or introduced, it sometimes
happens that when meadow or pasture land is broken up
and planted to grain, there is trouble from perennial weeds
whose roots or rootstocks remain in the soil. Thus, if a
meadow is infested with milkweeds and is planted to oats,
the milkweeds will multiply rapidly under the favorable

52 FARM FRIENDS AND FARM FOES —

conditions for their growth. In such cases rotation with a
hoed crop is desirable.

THE Parasitic DopDER

All the weeds so far discussed in this chapter injure the
crop by robbing the soil of food and moisture, or by oc-
cupying the space above the soil to the exclusion of the
cultivated plants. There is one group of pernicious weeds,
however, which do more than this, for they actually attack
the green tissues of the crop and rob them of the life-
giving sap. These plants are commonly called Dodders,
and there are several species that attack different crops.
In their life history, however, they are very similar to one
another.

The young Dodder plant starts from a seed well stocked
with nourishment. When the seed germinates, this nour-
ishment enables it to develop into a seedling which soon
comes in contact with the stalk of some green plant.
Then the little Dodder sends out from along the sides of
its own stalk curious rootlike projections that penetrate the
tissues of the other plant and draw out the sap. There is
thus established the relation of parasite and host: the
parasite is the Dodder sucking the lite sap from its victim,
which is the host plant. The root and lower stem of
the Dodder soon wither. In the case of clover, which is
often infested by Dodder, the clover plant continues to
-grow, having roots in the ground and leaves in the air,
but those clover stalks which are attacked by the Dodder
become dwarfed as well as hard and woody.

As the Dodder grows, it constantly twines around more
stalks of its host plant, sending into their tissues more of
the rootlike suckers, and after a time developing small
blossoms which later mature into seed. As the Dodder is

WEEDS OF GRAIN AND FORAGE CROPS 53

a parasite, it has none of the green coloring matter of
most plants, for it is not able to manufacture starch and
other organic material fromthe inorganic substances in
earth and air. Instead of this, it utilizes for its growth the
materials thus organized by the green leaves of its host.
The Dodders are commonly yellow or orange in color.
They have no leaves.

The seeds of Dodder are a common impurity in many
grain, grass, and forage seeds. Such seeds should, of
course, be carefully inspected before planting, and if seri-
ously infected should not be used. When a field is al-
teady infested, the Dodder may be destroyed by mowing
and removing the crop before the Dodder blossoms, or
later the crop. may be mowed and the ground burned over
after the crop thus cut has dried sufficiently to burn. In
Western alfalfa fields Dodder is often troublesome the
first year after seeding, though less so in later years.

PREVENTIVE MEASURES

Any study of the weeds that infest grain and forage
crops makes it obvious that the most important methods
of preventing injury by such pests are: first, the sowing
of clean seed, that is, grain free from the seeds of weedy
plants ; second, the use of fertilizers free from weed seeds;
and third, a proper rotation with other crops. To insure
pure seed, constant inspection by state and government
officials of all seeds offered for sale is necessary. To in-
sure fertilizers free from weed seeds, care in feeding do-
mestic animals is necessary. To insure proper rotation of
crops, the adoption of improved agricultural methods in
every community is necessary. With these conditions
right there need be little trouble from weedy plants in any
locality. There is always danger, however, that some new

54 FARM FRIENDS AND FARM FOES

pest will be introduced, and it is very desirable that the
people of each community should be on the alert for such
newly introduced weeds. In order that they may do this,
each school should have a collection of weeds and their
seeds for reference, and a study should be made of the
weedy plants of the locality. Any unknown plants may
be sent to the State Experiment Station, or to the Depart-
ment of Agriculture at Washington for determination.

OBSERVATIONS FOR PUPILS

1. What weeds have you observed in connection with such of -the
following crops as are largely grown in your locality : —

Alfalfa

Alsike Clover
Oats

Red Clover
Wheat

2. Is there any evidence to show that part of these were introduced
with seed? ,

3. Examine with a lens samples of forage plant seeds for sale in your
locality. Compare the seeds with the pictures in Farmers’ Bulletin 382.

4. Determine the percentage of adulteration of the crop seed with
other seeds. :

5. If you are unable to determine what seeds are present as adul-
‘terants, send samples to your State Experiment Station or to the Seed
Laboratory, Department of Agriculture, Washington, D.C.

READ such references in these publications as your teacher directs =

Dodder in Relation to Farm Seeds, Farmers’ Bulletin 306. The Adulteration
of Forage-p'ant Seeds, Farmers’ Bulletin 382.

CHAPTER V
The Economics of Weeds

Every farmer realizes that weeds are among the most
important factors in success or failure in agriculture.
They occur wherever the soil is cultivated and stand ever
ready to take the place of the crop planted if proper tillage.
is not given. They not only rob the crop of sunshine and
needed space in earth and air, but they
also deprive the soil of more-or less of its
available plant food, draw out its mois- |
ture, and according to the present belief
of some authorities actually poison the
soil for other plants.

Weeds, however, are by no means to |
be considered an unmixed evil. In many
cases they are rather to be thought of as
a blessing in disguise, for they compel
that tillage of the land which is neces- |
sary for the conservation of moisture and
the healthy growth of most crops. ‘“ The
truth is,” writes L. H. Bailey in a famous
paragraph, “that weeds always have
been and still are the closest friends and helpmates of the
farmer. It was they which first taught the lesson of the
tillage of the soil, and it is they which never allow the les-
son, now that it has been-partly learned, to be forgotten.
The one only and sovereign remedy for them is the very

55

MEADOWSWEET

56 FARM FRIENDS AND FARM FOES

tillage which they have introduced. When their mission is
finally matured, therefore, they will disappear, because
there will be no place in which they can grow. It would
be a great calamity if they were now to disappear from
the earth, for the greater number of farmers still need the
discipline which they enforce. Probably not one farmer in
ten would till his.lands well if it were not for these pains-
taking schoolmasters, and many of them would not till at
all. Until farmers till for tillage’s sake, and not to kill the
weeds, it is necessary that the weeds shall exist, but when
farmers do till for tillage’s sake, then weeds will disappear
with no effort of ours.”

While the beneficence of weeds .as a whole must be ad-
mitted as a fortunate fact, it is also true that often they
are not even a blessing in disguise. Like other things
in Nature, the laws that govern them involve many in-
conveniences in special cases. Rain is a blessing,
but sometimes it causes suffering and loss of prop-
erty and even of life. Winds are necessary, but
often do serious harm by their violence. With
weeds, as with these direct forces of Nature, man
must adapt his operations to suit-the conditions
that he finds upon his land in his efforts to make
it productive.

Examples of weeds that could easily be dis-
pensed with are readily pointed out. The Mus-
tard in a newly planted grain field does not indi-
cate that tillage is needed, although it does in-
dicate that there has been carelessness in seed
selection. During rainy seasons the hoe and cultivator
must frequently be kept in operation to subdue weeds
much oftener’ than any requirements of the crop alone
would necessitate. The weeds that appear late in the

Spud

ECONOMICS OF WEEDS 57

season in corn and potato fields require hand pulling
because tillage then would injure the crops, and often
even hand pulling involves some loss through the disturb-
ance ef the roots.

The most famous definition of a weed is that it is a plant
out of place. In soil devoted to a crop of a given kind,
_the presence even of other crop plants is generally not
wanted. So under some circumstances our ordinary grains,
vegetables, and flowers may appear as weeds. In fact, in
the case of the flowers many weeds have originated as gar-
den escapes, and there is always danger that new ones may
be so introduced. :

THE STRUGGLE FOR LIFE

It is well known that the most troublesome weeds are
those best equipped in the struggle for life. By being
able to grow quickly where other plants grow slowly, by
producing many seeds where other plants produce few
seeds, or by being able to do anything else that enables it
to get on in the world better than its neighbors a plant
has an advantage that tends to make it a weed. There is
always an intense struggle for soil, moisture, air, and sun-
light, and the plants best fitted to take advantage of con-
ditions existing at a given time and place will win. It is
the farmer’s business so to plan his operations that the
crops he sows will have the advantage of all weedy in-
truders.

One of the chief advantages that most weeds have in
the struggle for life lies in the production of great num-
bers of seeds. This is well shown in the following esti-
mates by the Kansas Experiment Station of the number of
seeds ripened by one plant, made after careful studies of
each species : —

58 FARM FRIENDS AND FARM FOES

NAME OF WEED NUMBER OF SEEDS
Purslane . ‘ ‘ ; ; . z . 69,000
Velvet leaf ‘ : ‘ : : : zi 31,900
Ragweed . . 2 “ A : : 23,100
Cocklebur : 5 F 3 . : F 9,700
Beggar-ticks a . : . : 10,500
Redroot . . 4 ‘ F ‘ ‘ 85,000
Tumbleweed 3 3 ” ‘i . ; . 14,000
Crab-grass . 5 5 j . . . . 89,600
Yellow Foxtail . . : a 4 é . 113,600

When plants are able to multiply at this rate, it is easy
to see how readily they might overrun the earth.

METHODS oF DISTRIBUTION

Under the conditions of Nature weeds are dispersed in
almost all the many ways in which plants spread. They
are carried by wind, water, and animals, and exhibit number-
less devices for taking advantage of these agencies. The
study of these devices is of great interest.

Under the conditions of modern agriculture, however,
man plays an important part in the distribution of weeds,
Vast numbers of seeds are carried from place to place in
hay, ballast, and packing materials, and even more are dis-
persed as impurities of grains and commercial seeds.

During recent years enormous numbers of weed seeds
have also been distributed in the various stock feeds upon
the market. Many investigations have shown that a large
part of these seeds are not digested, so that when they reach
the fields from the barn they germinate quickly. Asarule
these seeds are not readily detected in the feed because
they are mingled with chaff and grain or smeared over with
molasses. By careful studies, however, experiment station
officials have been able to identify and count these seeds
and to show the danger in the use of such feeds.

ECONOMICS OF WEEDS 59

‘The Connecticut Experiment Station has shown that in
the case of eleven feeds upon the market, there were the
following numbers of weed seeds in one pound of each: —

No. 1 11,528 No. 7 8,160
No. 2 7,800 No. 8 10,360
No. 3 29,324 No. 9 48,663
No. 4 22,224 No. Io 21,267
No. 5 8,574 No. 11 86,000
No. 6 27,100

The seeds thus present in such enormous numbers be-
longed to a comparatively few species of the most trouble-
some weeds. Among the most abundant of these were the
foxtail grasses, white pig-
weeds, knot-weeds, char-
lock, black mustard, rag-
weed, sorrel, docks, and
thistles. “All of these
weeds are characteristic of
grain screenings which are
the refuse separated from
the grain, in order to make
the latter marketable or fit
for milling. These screen-
ings vary a good dealin quality. Thus an analysis recently
made here of wheat screenings showed about 33 per cent
of flax and shrunken cereal, 15 per cent of foxtails, 8 per
cent of bindweeds and pigweeds, 15 per cent of weed seeds
of other species, and 21 per cent of dust, broken seeds,
and sand.”

BROAD-LEAVED Dock
Growth of First Season

LENGTH OF LIFE

One of the most important considerations in regard
to any weed is its length of life. If it lives but one

60 FARM FRIENDS AND FARM FOES

season, it is likely to be less dangerous than if it lives
two or more seasons. Like other plants, weeds are com-
monly grouped as aznuals, living but one year, dennzals,
living two years, and perennials, living many years. The
phrase winter annuals is given to those plants that start
their growth in autumn and finish their development the
following spring or summer.

The remedial measures to be taken against weeds depend
largely upon the term of life. The annuals live from year
to year by means of their seeds. Consequently the preven-
tion of seeding by tillage or other means and the destruction
of the seed are the most important general measures. It
has lately been found that some annuals like the mustards
may safely be killed in grain fields by spraying with a weak
solution of iron sulphate. The biennials reproduce also
by seeds, and are to be treated much asthe annuals. The
perennials commonly reproduce both by seeds and by root-
stocks or other vegetative growths, so that their destruction
is generally more difficult than in the case of the annuals
and biennials.

The methods that may be employed for the destruction.
of the roots or rootstocks of perennial weeds have been
well summarized by L. H. Dewey in these words : —

(1) They may be dug up and removed, a remedy that can
be practically applied only in small areas.

(2) They may be killed by applying chemicals either to
the freshly cut root or at the base of the main stem. Salt,
strong brine, coal oil, crude sulphuric acid, and carbolic
acid have been successfully used for this purpose. A few
drops of carbolic acid applied at the base of the main stem
with an ordinary machine-oil can is the best method that
has been yet devised for killing weeds with chemicals (ex-
cept spraying with sulphate of iron).

ECONOMICS OF WEEDS 61

(3) Rootstocks or perennial roots may be starved to
death by preventing any development of green leaves or
other parts above ground. This may be effected by build-
ing straw stacks over small patches, by persistent, thorough
cultivation in fields, by the use of the hoe or spud in waste
places, and by salting the plants and turning sheep on in
permanent pastures.

(4) The plants may usually be |
smothered by dense sod-forming |
grasses or by a crop like clover or |B
millet that will exclude the light. |

(5) Most rootstocks are readily
destroyed by exposing them to |
the direct action of the sun dur- |
ing the summer drought, or to the |
direct action of the frost in the |
winter. In this way plowing, for
example, becomes effective.

(6) Any cultivation that merely *

breaks up the rootstocks and

leaves them in the ground, especially during wet weather,
only multiplies the plant and is worse than useless, unless
the cultivation is continued so as to prevent the growth
above ground. Plowing and fitting corn ground in April
and May, and cultivating at intervals until the last of June,
then leaving the land uncultivated during the.remainder of
the season, is one of the best methods that could be pur-
sued to encourage the growth of couch-grass and many
other perennial weeds.

Recent studies by Spillman and Cates have shown that
the rootstock grasses, like quack grass, Bermuda grass, and
Johnson grass, are readily killed out by allowing the fields
to become meadows and pastures, so that a dense sod will

GOLDENROD SEEDHEADS

62 FARM FRIENDS AND FARM FOES

form. Then cut or feed off the grass frequently to induce
a shallow development of rootstocks. These may then be
turned up by shallow plowing and destroyed. by clean cul-
ture, summer fallowing, or winter freezing.

LESSONS FROM WEEDS

The most important general lessons we may learn from
our study of weeds are, first, that good agriculture is the best
preventive of their injuries, and, second, that this must be

"practiced not only by all the farmers of a given community,
but by all farmers everywhere. So it becomes the duty
of each one to adopt the best methods practicable on his
own farm as well as to encourage in every way possible
the practice of such methods in every locality.

OBSERVATIONS FOR PUPILS

Choose certain weeds which you have not before
reported upon and seeif you can answer these ques-
tions about each : —

Where did it come from ?

How does it spread ?

How long does it live ?

How does it pass the winter ?

How does it injure the crop ?

- Is it poisonous or hurtful to domestic animals ?
In what ways may it be destroyed ?

When you have a composition to write, choose

some weed for a topic and use these questions as an
HARDHACK outline for your guidance.

WANK EON a

PART Il

FRIENDS AND FOES AMONG THE
INSECTS

SLM

COVER DESIGN FOR A BOOKLET ON INSECTS

THE BOOKLETS ON INSECTS

At least two insect booklets may be prepared by each pupil, one on In-
sect Enemies and another on Insect Friends. The drawings and reports
upon the Observations for Pupils suggested at the ends of the chapters will
furnish abundant material for voluminous booklets.

In making drawings of insects so as to show a back view with each side
symmetrical, a butterfly with wings spread, for example, it is best to draw
one half beside a straight line, then to transfer this half by means of tracing
paper to the other side of the line. It is easier thus to get both sides alike.

CHAPTER VI

Orthoptera: the Grasshoppers, Crickets, and Cockroaches

THE Grasshoppers, Crickets, Cockroaches, Walking
Sticks, and a few other species make up the order of straight-
winged insects called Orthoptera. Practically all of them
are injurious, or capable of becoming so. With the excep-
tion of the Tree Crickets and the Mantids few of them are
likely to be of great service to man, except possibly as a.
source of food to poultry.

The insects of this order are characterized by having
biting mouth parts, incomplete transformations, and four
wings — the front pair usually being thickened, while the
hind pair are membranous and folded like a fan beneath
the front ones. This is a comparatively small group, but
one in which there are some very destructive species. In
America the Rocky Mountain Locust has done enormous
damage. In the Old World the locust plagues of both an-
cient and modern times were due to insects belonging to
this order.

STRUCTURE OF A GRASSHOPPER

If you examine a grasshopper carefully, one of the first
things you notice is that the body is divided into three im-
portant sections. At the front end is the “ead; next to
this are two closely connected parts that bear the legs
and wings and together form the ¢horax ; next to the thorax
is a part divided into rings — the abdomen.

65

66 FARM FRIENDS AND FARM FOES

The head varies greatly in shape with different species
of grasshoppers, but in general it is larger above than be-
low. From near the middle of the front there project two
slender feelers or antenne, each of which is composed of
a number of dis-
tinct rings or
segments joined
together. Just

MOouTH PARTS OF GRASSHOPPER above the base
uw, labrum; 4, mandible; ¢, tongue; d, maxilla; e, la~ of each antenna
bium. Magnified. is a large com-
pound eye, the surface of which through a lens resembles
the surface of ahoneycomb. Each eye hasa great number
of hexagonal divisions: these are the facets which make
up the compound eye. There are three simple eyes on the
grasshopper’s head — two between the compound eyes and
one in the middle line above. These are very different in
structure from the compound eyes, being merely small,
round, lenslike objects. These simple eyes are often
called oceliz.

Below are the mouth parts of the grasshopper. Begin-
ning from above, we see first a large four-sided flap or lip,
which moves up
and down on a
basal hinge ; this
is the upper lip mph
or lobes. Be GRASSHOPPER
neath it there is a pair of rather large jaws or mandibles
attached so as to move sideways, and having sharp, toothed,
cutting edges. On the inside of the mouth between the
mandibles is the tongue; and below this are the second
jaws or maxilla, while still lower is the underlip or /adium,
with its labial palps or feelers.

a

dult

GRASSHOPPERS AND CRICKETS 67

Directly back of the head, there is a large capelike seg-
ment bearing a pair of legs. This is the first division of
the thorax, and is called the prothorar. The remainder
of the thorax is made up of two parts united. The one in
the middle is the mesothorax ; this bears the front wings °
and the middle
legs. Behind this
is the metathorax ;
this bears the hind.
wingsand the hind
legs.

The front wings
are long and slen-
der, and when at rest serve as a protective covering to the
hind wings. The latter are then folded in longitudinal
plaits like a fan. When the grasshopper is flying, the front
wings are extended at right angles to the body, and the
hind wings are stretched out.

The abdomen is composed of a number of joints or seg-
ments, which move freely upon one another at their points
of contact. In female specimens the abdomen ends in
four-pointed projections by means of which the hole in the
ground for the eggs is made; these form the ovzpositor or
egg-depositor.

OBLONG LEAF-WINGED GRASSHOPPER

SHORT-HORNED Locusts

The common Grasshoppers or short-horned Locusts form
one of the most important families (Acridiidz). These
have short antennz or “ feelers,” short ovipositors, and but -
three joints to the zavsi— the short joints at the ends of
the legs. They feed upon grasses and other forage crops,
and are often very destructive. In many of the males,
there is a sound-producing apparatus.

68 FARM FRIENDS AND FARM FOES

The Red-legged Locust is one of the commonest
members of this family. Its eggs are laid in the ground
early in autumn and remain there
through the winter. The next sum-
mer they hatch into small grasshoppers
that resemble the adult in general ap-
pearance, but of course are much
‘smaller and have no wings. They
molt or cast their skins several times
during the next six weeks, and then
they become full grown with well-
developed wings.

The famous Rocky Mountain Locust
is very similar to the Red-legged spe-
cies. Fortunately it is unable to de-
velop continuously except at high al-
titudes, such as the plateaus of the
Rocky Mountains. Here it used to become so abundant
that it was forced to migrate
for food. Atsuch times, enor-
mous numbers of the grass-
hoppers flew toward the Mis-
sissippi Valley, where they
fed upon all kinds of grasses
and grains and many other
plants. As they came sud-
denly in enormous swarms, it
was impossible to fight them
successfully, and they often
did great damage.

There are many other spe-
cies of grasshoppers belong-
ing to this family, which are common and widely distrib-

COMMON CRICKET
Female

TREE CRICKETS
Male above; female below

GRASSHOPPERS AND CRICKETS 69

uted. The Carolina Locust is one of the most familiar.
It is abundant along roadsides and may be known by its
hind wings with yellow borders: The Bird Grasshopper
is our largest species.

MEADOW GRASSHOPPERS

The more slender Meadow Grasshoppers or Long-horned
locusts form another distinct family (Locustide). These
have long, slender antenne or “feelers,” conspicuous,
.sword-shaped ovipositors, and four joints to the tarsi.
Nearly all the members of this family are green in
color. They live chiefly on grasses and other herbaceous
plants, though some species are common in trees and
shrubs. The Meadow Grasshoppers, the Katydids, and
the wingless cricket-like Grasshoppers are the important
members of this family.

CRICKET FAMILY

The family to which the Crickets belong is called the
Gryllidz. These insects are characterized by having hind
legs adapted to jumping, long, slender antennz, and hori-
zontal wings with the outside edge turned down at a right
angle to the main part. In most Crickets there are pecul-
iar projections called s¢y/ets at the hind end of the body,
and there is usually in the females a spear-shaped ovipos-
itor.

The principal types of Crickets are Tree Crickets, Black
Crickets, and Mole Crickets. The first live on trees and
shrubs above ground, the second on the ground, and the
third in holes in the ground. In the case of the Black
Crickets, eggs are deposited in the soil early in autumn
and remain unhatched until the following season. Some
specimens, however, are generally to be found in winter in

qo FARM.FRIENDS AND FARM FOES

a half-grown condition, so that these insects may hibernate
in two stages of their life.

The Tree Crickets are generally greenish or whitish
insects, living on the leaves and branches of trees, shrubs,
and herbs. They feed upon plant lice or .
aphides, and thus differ in their food
habits from most of the order. But they
often do considerable damage to rasp-
berry canes by depositing their eggs in
long rows in the pith. Such canes are
likely to split open and winter-kill.

The Mole Crickets are among the most
remarkable examples of insect life. They
are perfectly adapted to an underground,
burrowing life. The front legs are de-
veloped into digging organs by means
of which the insect can make a tunnel
in the soil, through which the cylindri-
cal body easily. passes. They are brown
in color, and their food consists of under-
Mote Cricket ground roots of various sorts.

COCKROACHES AND WALKING STICKS

The Cockroaches (Blattidz) are characterized by their
flattened forms, their legs fitted for running, their flat over-
lapping front wings, and their long, bristlelike, many-jointed
antennz. Many forms of Cockroaches are wingless, though
the typical full-grown form has well-developed wings.
These insects feed upon almost anything, being commonly
found about kitchens and sheds, especially where there are
water pipes. Some species are also found in the woods,
under the bark of trees, where they feed upon a variety of
materials. Probably the original home of all the species

GRASSHOPPERS AND CRICKETS 71

was in the forest. The eggs are deposited in curious little
brown packets, that may often be found under the loose
bark of fallen logs.

The only other important members of the order Orthop-
teraare the Walking Sticks, which occasionally are injurious,
and the Mantids, which are generally useful in that they
feed upon various sorts of destructive insects.

OBSERVATIONS FOR PUPILS

SHORT-HORNED GRASSHOPPERS OR TRUE LOcusTS
A

1. Get afew good-sized grasshcppers — the larger the better. Kill
them in a cyanide bottle or by immersing in alcohol. Study the struc-
ture carefully to see if you can make out all the details mentioned on
pages 65-67 of this chapter.

2. Collect a lot of grasshoppers in a meadow or pasture. How do
the young differ from the adults? Rear a few in a vivarium, feeding
with clover or grass.

3. Place a piece of sod in the bottom of a box or a wide glas~ cylin-
der. Puta few full-grown grasshoppers in also. See if you get eggs
laid.

4- Look up some of these references : —

The Insect Book, pages 332-335. American Insects, pages 136-147. Nature Bi-
ographies, pages 89-95. Life Histories of -imerican Insects, pages 67-81.

B
1. Write or tell a story with this title : The Life of a Grasshopper.
Describe : —
Where and when the eggs are laid.
What the eggs look like.
When the eggs hatch.
What the young grasshoppers look like.
The growth of the young grasshoppers.
Their food.
When they become full grown.

2. Illustrate your story with sketches: if written, draw on paper ; if

told, draw on the blackboard.

72 FARM FRIENDS AND FARM FOES

LONG-HORNED OR MEADOW GRASSHOPPERS

1. Get a few Meadow Grasshoppers of different kinds and put in a
vivarium. Feed with clovers or grasses.

2. In what ways do these differ from the true locusts or common
grasshoppers ?

3. Watch to see if you can find out just how they sing.

4. Look up some of these references : —

The Insect Book, pages 336-340. American Insects, pages 149-156. Stories of
Insect Life, Second Series, pages 6-10.

CRICKETS

1. Collect some Black Crickets and keep in a glass vivarium with sod
in the bottom. Observe whether you can see them move their wings as
they sing. See if you can get some to lay their eggs.

z. You can generally get Tree Crickets in summer and autumn by
beating branches of trees and shrubs over an open inverted umbrella.
Keep some in a vivarium, providing aphides for them to feed upon.

‘3. Look up some of these references : —

The Insect Book, pages 341-344. American Insects, pages 157-161. Life His-
tories of American Insects, pages 45-58.

WALKING STICKS.

1. You can often get live Walking Sticks by beating branches over
an umbrella. Keep in a vivarium and insert leafy twigs for food.
Notice how quiet the insects remain by day.

2. Look up these references : —

The Insect Book, pages 323-325. Nature Biographies, pages 58-63.

CHAPTER VII

Hemiptera: The True Bugs

WHILE the word dug has been in common English use
for a long time as applying to an insect of almost any kind,
the entomologists restrict the word to a certain group of
insects which they call Hemiptera or Half-winged Insects.
The mouth parts of the members of this order are formed
for sucking, and the transformations are incomplete, their
life changes resembling those of the grasshoppers rather
than those of the butterflies and moths. An immense
number of noxious insects are included in this group,
some of the most notorious being the Squash Cy
Bug, Chinch Bug, the various kinds of aph-
ides or plant lice and of the scale insects or
’ bark lice, the Periodical Cicada, and many
other equally injurious pests.

The life history of these insects is well il-
lustrated by that of the common Black Squash
Bug. This pest appears in the garden in
early summer, and the females soon deposit
their eggs upon the young squash plants. \
These eggs are small, rounded objects, more ¢ \
or less triangular in their general outline. In aa
from six to fifteen days they hatch into tiny naira
bugs, which grow into the form and size of the parents.

The newly hatched Squash Bug is more brilliantly colored
than at any later time in its life, and these colors make it
very conspicuous against the green background of the

73°

14 FARM FRIENDS AND FARM FOES

leaves. The abdomen and the hind part of the thorax are
light green; the legs and feelers or antennz are a beauti-
ful crimson; the head and front part of the thorax are a°
light crimson; while the margins of the eyes are darker.
This brilliancy, however, lasts for a short time only. An
hour after hatching, the crimson is noticeably darker, and
in a few hours the insect is nearly black.

The young Squash Bugs soon begin their attacks upon
the plant by inserting their tiny beaks into the succulent
tissues of the leaves. In their general habits they resem-
ble the adults. .After about three days of this feeding, the
abdomen becomes noticeably swollen and the color some-
what lighter. This. is an indication that the period of
molting has arrived. These young bugs are often called
larve or nymphs. They now assume a quiet, stationary
attitude. The process of molting begins by the splitting
of the skin lengthwise along the middle of the back, the
split extending along the thorax and the front of the abdo-
men. .The time required to complete this molting opera-
tion varies greatly, but generally is not longer than an hour
or two.

A few hours after the first molt, when the bugs have
taken on their normal color, they are considerably lighter
than before. They are also more alert. They feed again
upon the sap of the leaves for about nine days, when they
undergo their second molt. After this has taken place, so
that the nymph is in its third larval stage, the body is
larger and flatter, with the margins more sharply defined
and the color somewhat darker than in the second stage.

The most notable difference shown by the insect in the
fourth stage, which is entered upon by the third molt about
eight days after the second, is the noticeable development
of'the wing pads. These become more conspicuous than

HEMIPTERA: THE TRUE BUGS 75

before. After living in this fourth stage for about a week,
the insect molts for the fourth time, entering upon its fifth
stage. It is now quite different in appearance, and is
easily recognized as a full-grown nymph, —a condition
analogous to the pupa state of butterflies and moths, in that.
it is the stage immediately preceding the adult. The
wing pads are greatly enlarged, while the thorax is wid-
ened and lengthened. The body is more rectangular and
so similar to a mature bug that at a little distance it may
readily be mistaken for the latter.

The full-grown nymph lives in this fifth stage about
nine days before the final molt, by which it matures into
the adult Squash Bug.

THE CnHincH BuG

The Chinch Bug has a life history similar to that of the
Squash Bug, but it does much more damage because it at-
tacks the great grain crops—corn, wheat, oats, and simi-
lar staples. The areas in which it occurs in greatest
abundance are shown by the dots on the map below. It
has been estimated that during the sixty years from 1850 to
1910 the losses due to this insect exceeded $300,000 coo.

The full-grown Chinch Bugs pass the win-
ter in the shelter of thick grass, fallen leaves,
or other protection, and come forth in the
spring. They then scatter to such grain
crops as they can find. Here they lay their
eggs, one bug often laying four or five hun-
dred eggs. The young bugs soon hatch and
attack the grain plants by sucking the sap
through their pointed beaks. When they are abundant,
they actually hide much of the surface of the leaf or
stalk, and of course kill the plants.

CHINCH BUG
Magnified

76 FARM FRIENDS AND FARM FOES

The young Chinch Bugs pass through a series of molts
very similar to those of the Squash Bugs. Those that
hatch from eggs laid in spring become full grown about
midsummer or a little later. They then lay eggs for an-
other brood. These become full-grown before winter and
hibernate in such protection as they can find.

The destruction of Chinch Bugs in their winter quarters
is one of the most effective remedial measures. By burn-

AREAS OVER WHICH THE CHINCH BUG OCCURS IN MOST DESTRUCTIVE
NUMBERS

ing over strips of grass lands along fences late in the fall
or early in the spring, many bugs may be destroyed. They
may also be attracted to strips or patches of trap crops,
such as millet, wheat, or corn, where they may be plowed
under or otherwise killed. They are often trapped in fur-
rows and killed by spraying with kerosene.

Under certain weather conditions these bugs may be
killed in vast numbers by the Chinch Bug Fungus—a
parasitic disease that spreads rapidly in moist air. This

HEMIPTERA: THE TRUE BUGS ~ 17

disease has been propagated artificially and distributed
over wide areas by state officials to good advantage.

Harieqguin CasBacE Buc

Throughout the Southern states, the Harlequin Cab-
bage Bug is one of the best-known insects. It is called
by many common names, due to its abundance and its con-
spicuous markings in red and black. It feeds freely upon
a variety of plants, but is most destructive to cabbages. Its
life history is very similar to that of the Squash Bug. The
barrel-shaped eggs are laid in clusters, commonly in two
rows of six eggs each. They soon hatch into small flat-
tened bugs that bear a general resemblance to the adults,
although, of course, they have neither wings nor wing
pads. These young nymphs suck the sap from the leaves
through their pointed beaks, and during the next month
shed their skins four or five times before they reach
maturity. There are several broods every year, and the
winter is commonly passed in the adult condition.

As the Harlequin Cabbage Bugs come from their winter
quarters very early and are readily attracted to mustard,
turnips, and other plants, it is generally practicable to use
these as trap crops. By planting, for example, a few rows
of mustard in the cabbage field, the bugs will be attracted to
these plants and may be readily destroyed together with
the plants by spraying with pure kerosene. . The field will
then be comparatively free from the pest, and those that
come later may be subdued by hand picking.

CicaDAS OR HARVEST FLIES

The Harvest Flies or Cicadas (Cicadidze) are the largest
insects belonging to the suborder Homoptera. Every one
has heard during the hot days of midsummer and early

78 FARM FRIENDS AND FARM FOES

autumn, the strange, shrill noise of the common Harvest
Fly, or Dog-day Cicada. This insect is present everywhere,
and its curious song is-one of the most striking and charac-
teristic of summer sounds.

The most famous member of this family, however, is the
strangely interesting Periodical Cicada or Seventeen-year
Locust. The adults of these insects appear in certain lo-
calities at intervals of either thirteen or seventeen years.
They may then be exceedingly numerous. At such times
they deposit eggs in the twigs of trees. These eggs soon
hatch into strange little larve that drop to the ground and
work their way through the soil until they find some roots
of trees or shrubs. Here they remain feeding and growing
very slowly for a long period of years. As already indi-
cated, in some regions they complete their development in
thirteen years and in others in seventeen years. By the
end of: this long time, the little larvae have become quite
large, and are of the shape shown in the lower illustration
on the next page. They now come to the surface of the
soil and crawl up the trunk of some tree or shrub, where
they emerge as adult cicadas. These are able to make a
curious shrill noise, somewhat similar to that of the Dog-
day Cicada, although in both species the ability to sing is
confined to the males. When the insects are very abun-
dant, the sound may become almost deafening.

Lear Hoppers

If with a close-meshed insect net, you sweep diligently
a few yards of meadow or pasture land, it is probable that
the most abundant insects you find in the net will be the
small, flattened, quick-jumping Leaf Hoppers (Jassoidea).
These insects vie with the plant lice in their enormous
numbers. They are likely to be present in any region.

PERIODICAL
CICADA

~ Adult emerging
from pupa

Full-grown pupa

80 FARM FRIENDS AND FARM FOES

So many of them, however, live concealed in grass lands
that most people have little knowledge of their abundance.
They are nearly all quite small insects, but doubtless do a
great deal more damage than is commonly attributed to
them.. They suck the sap from practically all kinds of

grains and grasses, and many infest trees,

shrubs, and other plants. They are

closely related to the Tree Hoppers found
on the twigs of trees.

The life history of many species of the
grass-feeding Leaf Hoppers has been carefully studied.
The eggs are laid in autumn in the grass blades and remain
unhatched through the winter. In spring they hatch into
tiny nymphs or larve that suck the sap from new grass
blades and gradually develop into adult Leaf Hoppers.
During this process they generally molt or cast their skins
four or five times, reaching maturity early in summer.
There seem generally to be at least two broods of the grass-
feeding Leaf Hoppers in a season.

In cases of great injury by these grass-feeding Leaf
Hoppers, it may be worth while to burn over the areas
most badly infested in winter or early spring, and thus de-
stroy the winter eggs. It has also been found that vast
numbers of the adult insects may be killed by the use of a
broad pan similar to the hopper-dozer often employed to
destroy grasshoppers. If this pan is covered with kero-
sene, tar, or some similar substance, the insects will be
caught and killed.

Many crop pests are found among the Leaf Hoppers
that feed upon vines, shrubs, and trees. The Grape Leaf
Hopper is one of the most destructive and widely distrib-
uted of these. Its life history has been carefully worked
out in New York, where it has been found that the adult

TREE HUPPERS

HEMIPTERA: THE TRUE BUGS 81

insects spend the winter under leaves and rubbish, or in
some similar shelter. They come forth rather early in the
spring and feed for two or three weeks upon the leaves of
raspberries, strawberries, and other plants. Early in May,
when the leaves of the grapes appear, these adult Leaf
Hoppers fly to the vineyards and attack the developing
foliage. They continue here for many weeks. The fe-
males deposit their small, whitish eggs in the green tissues
of the blades of the leaves, several eggs being inserted
side by side.

A fortnight later these eggs hatch into small larve or
nymphs that also suck the sap from the leaves and grad-
ually develop, passing through five molts before they be-
come mature. These young nymphs are able to run over
the surface of the leaves, but they do not jump as do the
fully developed Leaf Hoppers. They reach maturity dur-
ing the latter part of the summer and continue present
until October, when they seek shelter for the winter:
There is thus normally but one brood in a year, although
in more southern regions there are probably two broods.

The most effective means of combating this insect are
burning over the places of hibernation, destroying the
nymphs with a solution of whale-oil soap at the rate of one
pound to ten gallons of water, and trapping the adults upon
sticky shields held temporarily beside the vines.

The Apple-tree Leaf Hopper is another widely distrib-
uted destructive species. Examples of this may be found
on'the under side of apple leaves at almost any time during
the season. The Rose Leaf Hopper is another form that
may practically always be found upon rosebushes, where
the characteristic result of Leaf Hoppers’ injury may be
seen in the whitened spots on the upper surface of the
leaf.

82 FARM FRIENDS AND FARM FOES

Jumpinc PLant LIcE

The Jumping Plant Lice (Psyllidz) are few in number of
species, and with the exception of the Pear Psylla are of
comparatively little economic importance. This Pear Psylla,
however, often becomes a very serious pest, attacking pear
trees in overwhelming numbers, and sucking out the sap
to such an extent as to cause great injury. The adult
insect, which is only about the size of an ordinary plant
louse, passes the winter on the bark of pear trees, commonly
more or less concealed within crevices. They deposit their
eggs very early in spring, especially about the buds or
upon the unfolding leaves. In two weeks or so, the eggs
hatch into tiny larva which attack the petioles of the
leaves as well as their general surface. In about a month
each larva reaches maturity, having molted five times
during the process. There are several broods each year,
the number doubtless varying with the locality.

Like the aphides, these insects secrete a large amount
of the so-called honey dew, which consists chiefly of the
sap of the plant that has passed through the bodies of the
insects. Where a pear tree is badiy infested, this honey
dew covers the leaves, often collecting in large drops,
which are believed to act sometimes as lenses in condensing
the sun’s rays so as to burn the foliage beneath. Upon
this honey dew, there also develops a black fungus that
soon gives the leaves and fruit of the infested tree a strange
blackened appearance.

ScALE INSECTS OR CoccIDs

The strange Scale Insects or Coccids (Coccidz) form one
of the most important groups of the Homoptera. Many
of these are commonly known as Bark Lice, because they

HEMIPTERA: THE TRUE BUGS 83

are found so frequently upon the bark of trees. If you
examine the twigs or leafy branches of some apple trees,
you will probably: find what .look like miniature oyster
shells upon the bark. These are ex-

amples of the Oyster-shell Scale. If:
you will carefully pry up one of these

tiny scales and look at its under side

with a lens, you will probably find a

large number of minute oval eggs.

Early in summer, these eggs hatch into

tiny insects that wander over the sur-

face. of the young bark. Ina day or

two, they fix themselves in: one place |
by inserting their beaks into the tissues
and sucking out the sap, where they re-
main and gradually develop their scaly
covering.

One of the most destructive insects
ever introduced into America belongs
to this family. It is the notorious San
José Scale, a pest that during recent
years has attracted more attention from
fruit growers than any other insect.
It is especially dangerous because its presence is difficult
to detect until it becomes sufficiently abundant to injure or
kill the infested tree. It then appears as a curious scaly
crust on the bark. When only a few are present, they are
difficult to find, as they are simply small circular spots of
much the same color as the bark, plainly seen only through
a magnifying glass.

The appearance of the individual scales is well shown
in the pictures on the next page. Each scale is a
small circular object, closely attached to the bark, not more

SCALE INSECTS ON
ROSE

y

Much Magnified

SCALE

JOSE
INFESTED PEAR TwiG

SAN

Magnified

HEMIPTERA: THE TRUE BUGS 85

than one sixteenth of an inch in diameter, having a dark
raised point near the center. At first these scales are
likely to be scattered here and there over the bark, but as
they increase in numbers, they are found nearer together,
touching or overlapping one another. Finally, when they
become very abundant, they make a thick scurfy layer, of
a grayish color that obscures the natural color of the bark
and is easily rubbed off with
a knife. The presence: of
such a layer indicates that
the sap from the bark is be-
ing sucked out by millions
of the insects, and that the
health of the tree is being
seriously impaired.

The young scales that live
through the winter develop
in early spring into mature
insects, and each of the fe-
males may give birth to about
four hundred young. These are tiny yellow creatures that
crawl around for about a day before they finally fasten
themselves to the bark by inserting their curious beaks to
suck the sap. They then begin to secrete the scale which
is so characteristic of this family of insects. The scale is
composed of white waxy threads secreted bythe skin of
the larvae, which mat together to form a rather dense
covering. This whitish scale turns gray or even almost
black within a few days. The female scales are always
wingless, but the male scales develop into active two-winged
insects which are able to fly about.

When the San José Scale appears upon older trees, it is
most likely to be found on twigs and smaller limbs, but

* 86 FARM FRIENDS AND FARM FOES

upon young trees it may occur over the whole surface of
the bark. It does not confine its attacks to the bark, how-
ever, for leaves and fruit are often infested. Upon these,
as well as upon young bark, there is frequently a very
characteristic purplish ring around each scale. When the
leaves are infested, the insects are especially likely to be
found along the midrib.

This scale has commonly been introduced into new
localities by means of young trees from nurseries: There
are now rigid inspection laws in nearly all the states to
prevent the further distribution of the pest in this way.
The most effective remedy so far discovered, is that of
spraying in late autumn with a miscible oil or a lime-sulphur
wash. As is so often the case, the use of this lime-sulphur
wash has been found to have additional advantages in de-
stroying other insects and in preventing various fungous
diseases.

The Cottony Maple Scale is one of the most distinctive
members of the great family of Bark Lice. It may be
found in vast numbers, especially in the Middle Western
states, upon the twigs of the silver maple, and is easily
recognized by the mass of cottony tufts which are found
beneath each of the darker-colored scales. Early in sum-
mer great numbers of eggs are deposited inside of these
cottony masses. About three thousand eggs commonly
occur beneath each scale. In June or July these eggs
hatch into tiny larvae that wander over the leaves and soon
fix themselves, inserting their beaks to suck the liquid
from the tissues. Here they continue to develop until
shortly before the time for the leaves to fall. By this time,
the males mature into small winged insects that are able
to desert the leaves and fly about. The females, however,
crawl from the leaves to the bark of the neighboring twigs,

HEMIPTERA: THE TRUE BUGS 87

upon which they fix themselves and secrete a larger scale.
They remain on the twigs through the winter, and the
following spring complete their’ growth, produce the
cottony mass within which they lay their eggs, and finally
die.. There is thus but one brood each year. Fortunately
this insect, as well asmost other members of this family, is
commonly kept in check by its parasitic and other enemies.
The most important of these are small, black, four-winged
chalcid flies and various species of ladybird beetles.

THE APHIDES OR PLANT LICE

From the point of view of their destructiveness, the
Aphides or Plant Lice form one of the most important
families, not only of the true bugs, but of all insects.
During very recent years a single species affecting grain
has caused a loss of more than a million dollars in one
state in a single year. There are a great many species of
these little pests, of which the Green Flies of house plants
are familiar examples. They infest nearly all kinds of
crops, sucking the sap through their pointed beaks and
often causing enormous losses.

The life histories of the various species of Aphides are
quite similar. A good illustration is found in that of the
Spring-grain Aphis which has attracted much attention on
account of its damage to grain crops. Pictures of its vari-
ous stages much magnified are shown on the next page.
In many localities, it has been known as the “Green Bug.”
It is especially abundant in the more southern rather than
the far northern states.

Under normal conditions the Spring-grain Aphis passes
the winter in the condition of the egg, attached to leaves or
stalks of various grains and grasses. Early in the spring,
these eggs hatch into small plant lice that suck the sap

88 FARM FRIENDS AND FARM FOES

from the food plants and become full-grown in a very
short time, possibly a week or ten days. All of these
insects that thus hatch from the winter eggs are what are
known as viviparous females, because they are able to give

TAIT MRAIMLABHIC
PRUNG GRAIN-APHIS HineeeSs
De pyre foams yortar FEMALE

waar te +g SOT ERS a ee

y Pes

WINGED \ a

¥

birth to living young. Each insect produces a large
number ofthese young plant lice of the second generation,
and these in turn very quickly mature and give birth to a
third generation. This method of reproduction continues
throughout the spring, summer, and early autumn. ‘On
account of the rapid growth and of the large number of
young produced by each of the viviparous females, the
insect is able to multiply with astounding rapidity.

When the food plant is green and succulent, nearly all

HEMIPTERA: THE TRUE BUGS 89

the aphides are wingless forms, but when for any reason
the condition of the food plant is less favorable to the
development of the plant lice, large numbers of winged
viviparous females are developed. These are often called
winged migrants, because so many of them fly away to other
fields where they settle upon new plants and there give
birth to living young. In this way the insect commonly
spreads from field to field, and when it has wintered in the
South, it may gradually spread northward to infest new
localities.

When the grain crop ripens, the aphides usually migrate
to various kinds of grasses, where they continue to develop
throughout the summer, and migrate back again in autumn
to fields of young grain. In these fields they continue to
reproduce in the same viviparous manner until the approach
of cold weather. Atthis time a sexual generation is devel-
oped, the males commonly being winged, while the females
are wingless. The winter eggs are laid by these females,
and thus the yearly cycle is completed.

When the winters are mild, it very often happens that
this Grain Aphis is able to continue to develop through-
out the winter in its viviparous condition, so that ina given
locality we may have it passing the winter both in the
egg state and in that of various ages of viviparous females.
It is under such conditions that the greatest damage is
likely to occur, especially because of the fact that the in-
sects are able to thrive and multiply in a lower temperature
than is favorable to the development of the tiny parasitic
flies that commonly keep them in check.

An even more interesting life history is that of a closely
related plant louse known as the European Grain Aphis.
This insect is abundant and very generally distributed in
America. Its special point of interest is that it develops

go FARM FRIENDS AND FARM FOES.

in summer on various grains and grasses, and: migrates in
autumn to apple trees, where the winter eggs are laid.
Consequently, when we attempt to follow its history through
the year, we may begin in early spring with these eggs
upon the buds and bark of apple twigs, with this summary
as a result : — r

In early spring the eggs hatch into small aphides that
crawl at once to the, developing buds where they begin to
suck the juices of the unfolding leaves. In a few days,
this first generation from the egg, often called the stem-
mothers, begin giving birth to living young that also suck
the sap from the leaves and soon become mature. In this
way, four or five generations may develop on the apple in
spring. A large proportion of the later generations are
winged females, which fly away to settle upon grasses and
grains and start colonies upon these host plants. Conse-
quently these are called winged migrants. As a rule, all
of the plant lice of this species thus desert the apple before
midsummer.

The winged migrants upon grains and grasses establish
colonies that continue to increase throughout the remain-
‘der of the summer upon these food plants, one generation
following another in rapid succession. Rather early in
autumn, however, a generation of winged females, called
the return migrants, is developed from the grain and grass-
feeding colonies. These return to the apple, where they
give birth to a generation of wingless egg-laying aphides,
by which the winter eggs are laid upon twigs..

There are various other species of aphides which may be
found upon the leaves of the apple. The presence of these
other species has rendered the working out of the life his-
tory of this European Grain Aphis a much more difficult
problem than might at first appear.

HEMIPTERA: THE TRUE BUGS gi

It was formerly supposed that to a large’extent each
kind of plant was subject to attack by a special kind of
plant louse, but after careful studies were made of the
structure and life histories of the plant lice, it was found
that very often a single species
of the insects may attack sev-
eral species of plants. One of
the most striking examples of
this ability to live upon various
host plants is that of the Melon
Aphis, which infests an extraor-
dinary variety of host plants.
These include vegetable, field,
and fruit crops, as well as many
cultivated flowers and an extraor-
dinary number of weeds and
other wild plants. It has been
known by such common names
as Cotton Aphis, Orange Aphis,
and Dock Aphis. It is so com-
monly destructive to melons, cu-
cumbers, and related plants that
it is now generally called the
Melon Aphis, although in cotton-growing regions it is
known as the Cotton Aphis.

The life history of this insect is not very different from
that of the Spring-grain Aphis already described. The
winter is passed both in the egg state.and in that of the
viviparous females. Reproduction begins early in spring
and continues throughout the season, the insects multiply-
ing with marvelous rapidity and migrating from time to time
from one food plant to another. The ability of the species
to develop upon so great a variety of hosts renders it

EGGS
APPLE APHIS

yf

92 FARM FRIENDS AND FARM FOES

easy for the migrating females to find suitable food, and it
also renders the pest very difficult to fight successfully.

ANTS AND APHIDES

One of the most interesting things about the aphides is
their relation to various kinds of ants. If you look ata
colony of plant lice upon almost any tree or shrub, you will
probably find at least one kind of ant wandering around
among the aphides, and very likely you will find a regular
, procession of ants go-
ing up and down the
trunk -of the tree or
shrub. If you watch
one of these ants care-
fully, you will probably
see it find a plant louse,
touch it with the feelers
or antennz and very
ANT ATTENDING APHIDES UPON A WILLOW likely jap ee drop of

Twi liquid exuded by the

aphis, for these ants

visit the plant lice to obtain the liquids that pass through

their bodies. In-consequence, the plant lice are sometimes
referred to as the milch cows of the ants.

There are many strange and interesting things to be found
out concerning the relations of the ants and the aphides.
Toa very large extent, many species of aphides find friendly
helpers in the ants.. One of the most interesting examples
of this is the case of the Corn-root Aphis, an insect often
very destructive to corn crops in the Mississippi Valley.

This Corn-root Aphis is constantly attended by a small
brown ant that burrows out tunnels along the corn roots in
order that the plant lice may have a place to live. As the

HEMIPTERA: THE TRUE BUGS 93

numbers of the plant lice increase, the ants extend the
burrows to provide for them. The ants continue thus to
look after the needs of the aphides throughout the summer
months. In autumn, however, a still more interesting thing
takes place, for at this time an egg-laying brood of aphides
is developed and the small blackish eggs are taken by the
ants far down in their underground nests, where the eggs
are cared for throughout the winter. When the eggs hatch
early the following spring, the young plant lice are carried
by the ants, generally to the roots of some grass-like weed,
there to start the new season’s brood, which will be trans-
ferred later to the roots of the young corn plants.

In a case like that of the Cornroot Aphis, where the
eggs of theinsect pass the winter in the cornfield, rotation
of crops is the best means of reducing injury by the pest.
It is fortunate that there are great numbers of enemies of
aphides in general, for otherwise it would probably be im-
possible to grow many crops now produced. Many birds
feed freely upon the eggs and later stages of aphides, while
vast numbers of predaceous and parasitic insects develop at
their expense. The insecticides that are most effective in
destroying plant lice are kerosene emulsion, whale-oil soap,
and various decoctions and extracts from tobacco stems.

SENOS GES WEN SEENON’

SSS

ELM LEAF AFFECTED BY APHIDES

94 FARM FRIENDS AND FARM FOES

OBSERVATIONS FOR PUPILS

SquasH BuG

To what extent are these insects troublesome in your locality ? ?
What plants do they attack ?
What methods are used to kill them ?
Try placing shingles or small boards about the hills to see if the
bugs seek their shelter at night.
5. Make a drawing of the Squash Bug for your insect booklet.
Read : —

The Common Squash Bug, U. S. Bureau of Entomology, Circular 39.

PWN
eS

HARLEQUIN CABBAGE BuG

Is this insect common in your region?

. What plants have you known it to feed upon?

Have you seen the eggs? Where were they laid?

. What remedies have you known to be used against Harlequin
Cabbare Bugs?

PWN

CICADAS OR HARVEST FLIES

1. Have your ever known an outbreak of the Periodical Cicada? If
not, ask your friends about such outbreaks.

2. Do you know the song of the common cicada? How often do
you hear it? Is it more likely to be heard on hot or cool days? Did
you ever see one of the cicadas on a tree?

3- Read some of these accounts of cicadas : —

American Insects, pages 166-168. Stories of Insect Life, Second Series,
pages I-5.

Lear HOPPERS

1. Look on the under sides of the leaves of trees, shrubs, and herbs
to find leaf hoppers. Are they of different sizes and colors? You can
get many of them by sweeping grasses and herbage with an insect net
or by beating branches over an open inverted umbrella.

2. You will readily find the earlier stages of the leaf hoppers on many
leaves. Are the wings developed? Can the young hoppers jump like
the adults?

HEMIPTERA: THE TRUE BUGS

95

Bark LICE OR SCALE INSECTS

1. Look on apple twigs for the characteristic scales of the Oyster-
shell Scale. Pry up a scale and look on the under side with a lens.
In ie fall, winter, or early spring you are likely to find many eggs.

. Examine various fruit trees, especially
pee plums, and pears, for the San José
Scale. If found, learn whether the trees
have been sprayed to destroy them. In
autumn the scales are likely to be found
upon the fruits.

3. Examine other trees and shrubs for
other scale insects. In order to learn their
names, send such as you find to the Bureau
of Entomology, U.S. Department of Agri-
culture, Washington, D.C., with a letter
telling on what plant you found them.

APHIDES OR PLANT LICE

1. You generally can find these insects |
with very little trouble. Look on the leaves |
of apple or other fruit trees, or on willows or |

other trees. Look also on the leaves of
flowers and vegetables. Doall the different
kinds of aphides you find look alike?

2. In fall and winter look on the bark
of the willow branches and about the buds
of apple trees to find the winter eggs of the

CICADA EMERGING FROM
NYMPH SKIN

aphides. Examine them trouee a lens and make asketch for your inséct

‘booklet.

3. Many aphides live in gall-like modifications of the leaves. Make

sketches of such of these as you can find.

4. Read one ormore of these references : —

American Insects, pages 171-176. Life Histories of American Insects, pages

209-247.

CHAPTER VIII

The Butterflies and Moths

THE great order of insects to which the butterflies and
moths belong is called Lepidoptera, a word meaning scale-
winged. This name was given to the group because each
of the beautiful wings with their varied colors and markings

is. composed of a thin

PROMETHEA MOTH COCOON

membrane, to which are attached
vast numbers of tiny scales over-
lapping one another, much like the
shingles of a house. The insects
of this order have sucking mouth
parts and. two pairs of wings. The
transformations arecomplete. The
period of growth and feeding is
that of the larva or caterpillar, the
adults eating only the nectar of
flowers or similar substances, or,
in some cases, taking no food at
all.

This order includes a large num-
ber of species, varying greatly in
size and habits. Some of the moths
are so tiny as to be barely visible

to the unaided eye, while others are so large and conspic-
uous as to attract attention at considerable distances. By
far the largest proportion of the species feed in the larval
state upon the tissues of plants, and consequently a great
many injurious insects are found in the order.

96

THE BUTTERFLIES AND MOTHS 97

THE BUTTERFLIES

The highest group of the Lepidoptera is the great super-
family to which the butterflies belong; this is commonly
called the Papilionina. This includes four distinct families
which need not be considered specifically here.

The butterflies as a group are day-flying insects, with.
knobbed antennz or “feelers,” small bodies, and compara-
tively large wings. The caterpillars do not spin cocoons,
changing to the pupa state as naked chrysalids, although
often there is a loop of silk over the shoulders to hold the
chrysalis in position. These caterpillars have three pairs
of true legs and five pairs of prolegs.

A familiar example of the life history of a butterfly is.
found in the common Cabbage Worm, the adult of which
is the common white butterfly, with black spots upon the
wings, which is to be seen flying about gardens throughout
the summer. These butterflies lay eggs upon the cabbage
leaves. The eggs soon hatch into small greenish larve
that feed upon the tissues of the leaf for a few weeks,
molting or casting their skins four or five times during this
period. When full grown, they find some sheltering leaf,
stone, or board, beneath which they change to the chrysalis
state, to emerge a short time later as adult butterflies.

While as a group the butterflies have by no means as

. Many injurious species as have the-various groups of moths,
a number of rather destructive insects belong to it. One
of the most widespread of these is the Black Swallow-tail
or Asterias Butterfly, the Jarvee of which feed upon the
leaves of celery, carrots, parsnips, and various other mem-
bers of the parsley family. These caterpillars are green,
marked with black, and may very commonly be found upon
the garden plants mentioned. Another species, which is

98 FARM FRIENDS AND FARM FOES

often destructive, is the Mourning Cloak Butterfly, the
caterpillars of which frequently defoliate willow, poplar,
and elm trees, so that in some localities they are called the
Spiny Elm Caterpillars.

An even more generally destructive butterfly is the larg-
est of our North American forms, called the Cresphontes
Butterfly. This is a Southern species, being, however,
widely distributed as far north as Massachusetts, New

ORANGE-DOG CATERPILLARS

York, and Illinois. Throughout the orange-growing re-
gions, the caterpillars are commonly known as “Orange-
dogs,” because they feed so largely upon the leaves of

THE BUTTERFLIES AND MOTHS 99

orange trees, being especially destructive to young plants
in the nursery. They are curious-looking caterpillars, and
doubtless their unusual appearance, possibly suggestive of
a watchdog, has given rise to the common name.

Briefly summarized, the life history of the Orange-dog
Butterfly is this: The eggs are deposited singly upon the -

—_—— x i
BUTTERFLY OF ORANGE-DOG CATERPILLAR JUST EMERGED FROM CHRYSALIS

young growth of the orange, generally near the tips of
leaves or branches. In a week or more they hatch into
tiny caterpillars that feed upon the tender foliage. When
not eating they rest upon the lower surface of the leaves.
In about a week, they becoime too large for the skin with
which they were born, and they. molt or cast’ their skin,
coming forth with a new one that had been formed beneath

100 FARM FRIENDS AND FARM FOES

the old. They then feed again for a week or so before
molting for the second time.

These processes of feeding and molting are commonly
continued for four or five weeks, the caterpillars eating
more and more of the leaves as they grow older. They no
longer confine themselves to the succulent young leaves
and shoots. A single insect may do much damage to a
young tree, as it consumes a relatively large amount.of the
growing tissues of the plant. When full grown in the
caterpillar stage, the insect changes to the chrysalis, gen-
erally attaching itself by silken threads to the bark of a
twig or branch of the orange tree. The chrysalis takes on
the same general coloring as the surrounding bark, so that
it becomes decidedly inconspicuous. In a little less than
a fortnight it emerges as an adult butterfly.

Like the caterpillars of the other Swallow-tail Butter-
flies, these Orange-dogs have curious yellowish scent organs,
which protrude from the upper surface just behind the
head. When the caterpillar is disturbed, these give forth
a very disagreeable odor, which is believed to serve as a
means of repelling birds and possibly other enemies. At
any rate, good observers have noticed that the insect is not
molested by birds, although it is known to be subject to
attack by various insect parasites. Each female butterfly,
apparently, is able to deposit four or five hundred eggs,
-and one of the interesting ways suggested for preventing
the injuries of the caterpillars is to shoot the butterflies
upon the wing with cartridges loaded with sand or small
bird shot.

SpHinx Morus

A beautiful family of the scale-winged insects is that of
the Sphinx Moths or Sphingidz; these’ are. commonly:

THE BUTTERFLIES AND MOTHS IOI

called Hawk Moths. They are characterized by having
large bodies, with small wings and very long curious
tongues, which sometimes reach a length of five or six
inches. Nearly all of them fly just at twilight, rather than
during the day. The family includes a large number of
species, several of which are injurious to cultivated crops.

Most of the caterpillars of the Hawk Moths have the habit
of assuming during the day a curious attitude, with the
head end of the body held rigidly erect in a way suggestive
of the famous Sphinx of Egypt. To this is doubtless due
their common name of Sphinx Caterpillars. A familiar
illustration of these larvae may be found late in summer on
tomato, potato, tobacco, and related plants, for the common
tomato and tobacco worms belong to this group. There
are really two species .of these tomato worms, one being
more abundant in the North, and the other in the South.
When full grown the caterpillars burrow into the-soil, where
they change to brown pupz, and early the following sum-
mer wriggle to the surface of the soil, to emerge as beauti-
ful grayish Hawk Moths.

Another common, widely-distributed member of this
family is the- Pandorus Sphinx, the caterpillars of which
are often injurious to grapevines and Virginia creepers
or woodbines. The moth is large and beautiful, exquisitely
colored in greens and browns. The eggs are laid early in
summer upon the leaves of the food plant, hatching in a
few days into small sphinx caterpillars that feed and molt
for several weeks before becoming full grown. They are
then three or four inches long, and the thickness of a man’s
finger. They now crawl to the ground and burrow into
the soil a short distance, where they change to pupa, to
remain until the following season, when they emerge as
moths. ,

102 FARM FRIENDS AND FARM FOES

SILK-SPINNING MortTHs

One of the most important groups of the Lepidoptera
is that of the silk-spinning moths (Bombycinz), of which
the most famous is‘the silkworm of commerce. Asa rule,
the bodies of the Bombycine Moths are large and thick,
and the mouth parts are generally inconspicuous or absent
altogether. In the latter case the adult moth is unable to
take any food, consequently these moths are seldom to be
seen visiting flowers, as do the Hawk Moths and the Owlet
Moths. The caterpillars are frequently thickly clothed
with hairs, and they nearly always change to pupe within

the protection of
silken cocoons.
The .families of
this group in-
clude some of the
insects most de-
structive to vege-
tation.
The most beau-
tiful American
insects are the
larger forms of
the Bombycine
Moths. The
wonderful trans-
lucent beauty of
the Luna Moth,
the handsomecol-
oring of the Ce-
cropia Moth, and the glorious browns of the Polyphemus
Moth deservedly attract the attention of every one that sees

|
4

LuNA MOTH: Reduced

THE BUTTERFLIES AND MOTHS 103

them. The curious cocoons of the Promethea Moth fas-
tened so securely to the branches of many trees and shrubs
may be found throughout the winter over a large part of
North America, and, if brought indoors, will yield a har-
vest of attractive moths in early summer.

The familiar Tent Caterpillar, the nests of which are to
be found in so
many wild cherry
and apple trees
during May and
June, is also a
smaller example
of one of these
families of © silk
spinners. These
Tent Caterpillars
are very easily
reared indoors, so
that it is easy to
watch them spin
their cocoons, ‘
change to pup, and emerge later as rather small brown
moths.

The most notorious member of the nearly related family
of Tussock Moths is the destructive Gypsy Moth, which
during the last few years has done enormous damage in
New England, and millions of dollars have been spent in
fighting it. This Gypsy Moth is a native of Europe and
was introduced into America about 1869. Since then
it has gradually spread from the Massachusetts town where
it first escaped, and threatens to become one of the most
widespread and destructive of insect pests. It is very
desirable that people everywhere should be on the watch

104 FARM FRIENDS AND FARM FOES

for it, so that on its first appearance in a new locality it
may be promptly exterminated.

The adult Gypsy Moths appear upon the wing during
the latter part of summer. The females are larger than
the males, having a wing expanse of nearly three inches,
and are of a whitish color. Their bodies are very large
and heavy, so that the moth is able to fly only to a very
slight extent. The male moths have a wing expanse of
less than two’ inches, and are of a brownish-yellow color.
Their bodies are slender, and the moths are able to fly
readily.

Soon after emerging from the cocoons, the female moths
deposit their eggs in characteristic masses, each mass com-
monly containing about five hundred eggs. They are very
likely to be deposited in such hiding places as hollow trees
or logs, or among the stones of stone walls. These eggs
remain unhatched until about the time the leaves begin to

appear the following spring. Then they hatch into tiny
caterpillars that feed upon the leaves. These grow rapidly,
molting several times as the weeks go by, until finally they _
become full-grown hairy caterpillars that change to pupz
within very slight silken cocoons, if, indeed, the few silken -

THE BUTTERFLIES AND MOTHS 105

threads that commonly protect them may be called cocoons
at all. A short time later they change again to adult
moths.

The special aanger from these Gypsy Moths is due to the
fact that they multiply so rapidly, feed so ravenously, and
attack practically all kinds of growing plants, including even
the coniferous evergreens. They are as yet comparatively
little injured by birds or parasitic enemies, although every
effort is being made by official entomologists to introduce
into this country the various parasites that keep the species
in check in Europe.

The Fall Web-worm is a caterpillar easily found during
late summer and early autumn. Its unsightly nests occur
upon a great variety of fruit and shade trees. These Web-
worms hatch from eggs laid in clusters upon the leaves by
a whitish moth. The tiny caterpillars begin to spin a pro-
tective-web as soon as hatched. When very young they
are yellowish, marked with black, and have a few hairs
projecting from their bodies. They spin webs over the
nearer leaves and then feed upon their green substance,
eating this out so that the network of veins is left. As the
days go by, they enlarge the web to cover other leaves,
which are in ‘turn attacked. They molt about once a week,
remaining always beneath the protecting web. As they
become full grown, the caterpillars eat more or less of the
veins along with the leaf substance, but they generally avoid
the midribs.

The full-grown Web-worm caterpillars are a little more
than an inch long, with the body densely clothed with
yellowish hairs. They now leave the trees and descend to
the ground. There they spin slight silken cocoons within
which they change to the chrysalis state, and remain until
the following June, when they emerge as moths to lay eggs

106 FARM FRIENDS AND FARM FOES

for another brood of Web-worms. There is thus but a single
generation in a season.

One of the most destructive moths that has ever ap-
peared in America is the famous Brown-tail Moth, which
has already done an enormous injury in New England,
and which threatens to become widely distributed over the
country. This pest seems to have been accidentally intro-
duced with a shipment of nursery stock from Europe. It
is especially troublesome not only because the caterpillars
feed upon practically all kinds of deciduous trees, but also
because their bodies are covered with poisonous hairs that
cause great suffering when they get upon the human skin.

The Brown-tail Moth passes the winter in characteristic
nests composed of compact masses of leaves fastened to-
gether by silken webs. Inside each of these nests, there
are commonly several hundred tiny caterpillars. When
spring comes, these little caterpillars leave the nests when
they wish to feed, crawling along the twigs until they
reach foliage. At first they return to the nests at night
and when not feeding, but as they grow larger, they are
likely to desert them altogether. They continue to feed
and grow until about the middle of June. Each caterpillar
then spins around itself a silken cocoon, which is attached
to some convenient. shelter, commonly the leaves of the
food tree. Inside these cocoons, the caterpillars change to
chrysalids, and three or four weeks later again change to
the peculiar whitish moths, with a tuft of brown hairs at
the end of the body of the females. This tuft gives the.
insect its common name.

These moths appear in June, and lay eggs in clusters of
two or three hundred each on the leaves, generally near
the ends of the branches. During the latter part of the
summer these eggs hatch into ‘small caterpillars, which

THE BUTTERFLIES AND MOTHS 107

feed upon the leaves, forming gradually’ the: protective
nest that remains upon the trees through the winter. The
caterpillars remain inside the webbed leaves, and thus
wait until the following spring.

An effective remedy for this insect is that of burning
the winter nests. In localities where it is not yet found, a
constant watch should "be kept for it, and any suspicious-
looking nests should be sent to the State Experiment
Station for examination.

OwLet Motus

Another important family of the Lepidoptera is that of
the Owlet Moths, or the Night-flying Moths (Noctuidz).
These. are comparatively small moths, having thick bodies,
slender antennz, rather small wings, and for the most
part inconspicuous colors. The larve are generally
smooth-bodied worms, that commonly trarisform into papz
in earthen cells. This group includes a large number of
very destructive insects, of which the Army Worm and the.
Cutworms are good examples.

For more than:’a hundred years, the Army Worm has
been destructive to American crops. It is one of those
insects which appear at irregular intervals in enormous
numbers, and then suddenly disappear for many years.
Briefly told, the story of the life of the individual Army
Worm is this : —

On some summer night there appears flying about a
meadow, a rather large, light-brown moth. She finds a
cluster of grass blades. Into the folded leaves of one or
more of these, she pushes a number of small, whitish
eggs, grouping them in rows of a dozen or more. A week
or ten days later, each egg hatches into a minute whitish
worm, that nibbles at the grass blades at night, andduring _

108 FARM FRIENDS AND FARM FOES

it is about to enter.

duces a hollow cell.

the day hides beneath the grass from the rays of
the sweltering sun.
This larva grows rapidly in size. At the end

of a week it molts or casts its skin, a process in

which the old
skin splits open
along the back,
and the worm
crawls outclothed
in a new skin that
has developed be-
neath the old one.
Again it feeds as
before, its vo-
racity increasing
with its size. This
molting is re-
peated four or five
times during the
month after the
eggs hatch, so
that by the end
of this period, the
insect’ is one and
a half inches long,
and has the brown

markings of the full-grown Army Worm.

The instinct of the caterpillar now teaches it to seek
more secure shelter for the helpless stage, upon which
It burrows into the soil an inch
or less and wriggles about in the earth until it pro-
In this it casts its skin again and

becomes a pupa—the third stage of its existence. When

THE BUTTERFLIES AND MOTHS 109

the caterpillars are very abundant, many of them do not
go into the ground, but change to pupz beneath whatever
shelter may be at hand. About a fortnight later, another
change takes place, and the fully developed moth emerges
from the pupa, thus completing the cycle of the insect’s
life. The moths fly toward dusk and at night, and by
means of their long tongues, coiled up when not in use,
they suck the nectar of various flowers.

During ordinary years the Army Worm is present in
most of the regions where its outbreaks occur, individual
caterpillars feeding in meadows and pasture lands, but the
number is not sufficient to attract notice. At such times,
their habits of life are very similar to those of the common
Cutworm, to which, indeed, the Army Worm is closely re-
lated. It is only when the caterpillars become so nu-
merous that they exhaust the food supply of the field in
which they develop, that the “army” habit is assumed.
Then, however, they are forced to seek new quarters for
food, and as their only mode of progress is by crawling
along the ground, they move in solid masses toward ad-
jacent fields. They feed preferably upon the various
grasses and grains, although, when driven by hunger, they
will eat the leaves of clover and other plants.

One of the most effective means of preventing the in-
juries of these armies of caterpillars is to dig a deep ditch
or trench, into which the worms fall in great numbers,
where they can be destroyed by various mechanical devices.

The Cutworms form one of the most vexatious groups
of injurious insects. They are the smooth-skinned, thick-
bodied worms, an inch or so in length, which are so often
to be found by careful digging about a tomato or cabbage
plant that has been cut off in the night. They attack a
great variety of crops and often cause serious losses.

110 FARM FRIENDS AND FARM FOES

The Cutworms are the young or larve of rather large
millers, or night-flying moths of the family Noctuidz. One
of them is represented natural size in the figure ‘below.
In the case of several of our common species—for there
are many different kinds of Cutworms
pt — these moths lay eggs in grass lands

ROEM LARS late in summer or early in autumn.
The eggs soon hatch into small worms that feed upon the
grass until ‘cold weather, when they seek such shelter as
can be found in the soil or rubbish at or near the surface
of the soil, and remain quiet until spring. They are likely
to be half grown when winter closes in..

When the sunny days of April come, the Cutworms
again begin to feed. If the grass land has been plowed,
they eat.such green things,as they can find, until the corn
or other crop'comes up; then they feed upon it. If they
are in grass near gardens, they are likely to wander over
the garden more or less, taking such plants as they find.
They travel at night, remaining concealed in or near the
soil during the day.

Toward the latter part of the spring the Cutworms be-
come full grown in this larval state. They then burrow
into the soil, and change to pupz or chrysalids of a
brownish color. About two weeks later they again change
to adult moths.

Various remedies for Cutworms are known. In gardens,
when a plant has been cut.off, a prompt search of the soil
about the base of the:stem will generally reveal the worm,
which may then be killed. On a larger scale, the use of a
poisoned bait made by mixing a small amount of Paris
green with bran or middlings, or a mixture of the two, has
been successful. This is scattered upon the grass beside
the field to be protected, or is placed in rows in the field

THE BUTTERFLIES AND MOTHS Itl

itself. But great care is of course necessary in such use
of poisons.

It is not often that an insect attacks three crops which

are so different in every way as cotton, corn, and tomatoes.
This is the case, however, with the noctuid moth, known
by the various names of Bollworm, Corn Worm, and To-
mato Fruit Worm. The cater- |
pillars have a general resemblance |
to some of the commoner cut- |
worms, although they vary greatly |
in color and markings. In the
Southern states, these caterpillars |
feed to a destructive extent upon |
the bolls of cotton, on account of |
which they are called Bollworms. —
In regions farther north, these
caterpillars feed inside the husks |
of green corn, upon the tassels and
immature kernels; on account of
which they are commonly called COGN BOLLWORM
Corn Worms or Tassel Worms.
In some regions where tomatoes are largely grown, these
caterpillars feed upon the green fruit, often boring into it
in a very destructive manner; consequently, they have re-
ceived the name Tomato Fruit Worm. In the South, how-
ever, the insect does not confine its attention to cotton, for
it often feeds also upon green corn even in cotton-growing
regions.

As a Corn Worm, the life history of this insect may be
summarized in these words: The adult yellowish or yel-
lowish-green moths appear in the cornfield early in the
summer and deposit their eggs upon the leaves or stalks
of the growing plants, Four or five days later these eggs

112 FARM FRIENDS AND FARM FOES

hatch into small caterpillars that commonly hunt until they
find the end of a young ear of corn, where they feed upon
the green tassels and gradually burrow beneath the husks,
eating both tassels and young kernels as they proceed.
When once beneath the protection of the outer husks, they
remain until they become full grown. They are then a
little over an inch long. Each makesa round hole through
the husk and enters the soil below the plant, where within
an oval cell it changes to a pupa. Some time later it
again changes to an adult moth.

The life history of the insect when it feeds upon cotton
is very similar, except that the young cotton bolls are at-
tacked instead of the ears of corn. An interesting fact in
regard to the species is that in the more northern regions
this insect does not seem to be able to survive the winter
in any stage. Consequently, it is believed that most of
the injury there done each season is caused by moths that
fly northward from the south.

The Larger Cornstalk-borer, which is alse known as the
Sugarcane-borer, is one of the most: generally destructive
insects in the Southern states. Early in spring, about the
time the young corn plants are four or five inches high, a
rather small moth appears in the fields and lays eggs upon
the leaves of the young corn plants. These eggs soon hatch
into small caterpillars that burrow into the stalk until they
reach the pith. Then they begin feeding upon this pith,
usually burrowing upward. They continue to feed and
grow for several weeks, often coming out of -the original
plant and burrowing into a neighboring one. About mid-
summer, they become full grown in the larval state. Then
they change to pupz inside the tunnels within the corn-
stalks, to emerge a fortnight later as adult moths.

These moths lay eggs for a second generation of cater-

THE BUTTERFLIES AND MOTHS 113

pillars, that burrow into the cornstalks in the same way,
and usually remain through the winter in their tunnels with-
out transforming to pupz. Early in spring, however, this
transformation takes place, and the moths appear in time
to lay their eggs upon the young corn plants of a new
season.

This Cornstalk-borer is especially destructive in regions
where old cornstalks are left in the field through the winter.
The destruction of these, with the hibernating caterpillars
inside, will very largely reduce the injury the following
season. It is another one of the numerous insects which
point the moral that “ good agriculture is the first and best
insecticide.”

Copiinc Motu

It is more than a century since the Codling Moth or
Apple Worm began to prey upon the fruit of American
‘orchards. This pest was
introduced from Europe
early in our history. Its
life history in brief is
this : —

The parent insect is
a small chocolate-brown
moth, scarcely half an
inch long, which appears
among thetreesin spring
about the time the young
apples are forming. The
tiny whitish eggs are de-
posited upon the fruit,
stems, or leaves. These eggs shortly hatch into small larvae
that commonly enter the blossom end of the apple, where

114 | FARM FRIENDS AND FARM FOES

they are likely to nibble for a few days before they burrow
down toward the core. When once within the fruit, they
feed and grow for about a month. Then they leave the
fruit and find shelter where they spin their cocoons, within
which: they change to pup. Each insect remains in this
pupal state for about two weeks; then it emerges as an
‘ adult moth, like the
one that laid the
original eggs.

These moths com-
\ monly lay eggs for
‘a second brood of
/ worms, that de
velop in the apples
throughout the late
summer or eatly au-
tumn months. The
larve leave the ap-
if ples when fullgrown
and, in the shelter of rough bark or something similar, spin
silken cocoons, within which they remain until about the
time the apples blossom the following spring.. Then they
change to pupz, and change again in about two weeks to
adult moths. There are two broods of these moths a year,
each distributed over a long period.

The injuries of the Codling Moth larve may be pre-
vented to a large degree by spraying with arsenical poisons
in spring, soon after the petals of the blossoms have fallen.
It is especially desirable that a thorough spraying be given
before the calyx end of the young.apple is closed. In the
picture above, the calyx in each of the outer fruits is open;
that of the larger, middle fruit is closed. By means of the -
spraying machine, the fruit grower is able to place in the

AppLEs SHOWING CALYX OPEN AND CALYX
CLOSED

THE BUTTERFLIES AND MOTHS 115

upper or blossom end of the apple a few particles of poison,
so that when the newly hatched worm nibbles at the skin,
it is likely to eat one or more of these particles and be killed.
Two sprayings are generally desirable ; the first less than a
week after the petals fall, and the second ten days er two
weeks after the first.

Lear RoLtiters anp LEAF MINERS

Examples of the great group of Leaf Rollers, several
families of which are commonly classed together into one
superfamily (Tortricina), are easily found wherever there
are trees or shrubs in variety. These insects are espe-
cially characterized by the ability of the
larve to fasten together the edges of ¢
leaves by means of silken threads.
Sometimes it will be a single leaf
cleverly rolled into a tube, and at other
times it will be a number of leaves upon
the same branch, sewed together to make a tent. In
either case, the leaves thus united are utilized as a home
for the young caterpillars, that feed upon the green sub-
stance on the inside, and so escape, to a large extent, the
attacks of birds.

When fully grown, the caterpillars change to pupae,
either in the webbed home or in some other shelter, and
a little later they change again into small moths. One of
the commonest examples of this great group is the so-
called Rose Leaf Roller, which is also often found upon
the leaves of apple and many other trees. Fortunately in
the case of most Leaf Rollers, the protecting web does
not prevent the access of parasitic flies which destroy the
caterpillars in great numbers.

The smallest of the scale-winged insects belong to the

LreaF ROLLER’ MOTH

116 FARM FRIENDS. AND FARM FOES

great group of Leaf Miners (Tineina). For the most
part, these insects in their:larval stages live between the
upper and lower surfaces of leaves as true miners. Some
of them, however, have other habits. A comparatively
small number make tiny silken cases-which serve as houses
within which they live. Others burrow in fruits, stems,
or seeds. Still others feed upon wool or furs or feathers ;
the common clothes moths are illustrations of these.

.. If. you will look carefully at the leaves ef the nearest
apple tree, you will belikely to find illustrations of the true
Leaf Miners.: . Several distinct species live upon the tissues
of apple leaves. : One of the commonest is the Apple-leaf
Trumpet Miner, which is easily recognized by the curious
trumpet shape of the yellowish mine that is conspicuous
within the ‘green tissues of the leaf. The life history of
this species is very simple... A small brown moth lays her
egg upon: the surface of the leaf. The egg shortly hatches
into a tiny larva, that burrows through the’skin of the leaf
and feeds upon the green cells inside. Here it continues
to feed and grow for some weeks, casting its skin occasion-
ally. It remains as a Jarva within the mines when the
leaves fallin autumn. In the spring it changes to a.pupa,
still within the fallen leaf, and a little later the. moth
emerges. This insect is sometimes so numerous as seri-
ously to‘injure the foliage of the trees. -

PEACH-TWIG BORER

The insect which in California is known as the Peach
Worm and which in many other parts of the country. is
called the Peach-twig Borer,’is one of the most extraor-
dinary of fruit insects. This is due to the remarkable varia-
tion of the habits of the larve in the three aificrent broods
developed during each year.

‘THE BUTTERFLIES AND MOTHS — 117

‘The life history of this pest in California’ has been very
carefully worked out by the investigators ‘of the State Ex-
periment Station. In brief it is as follows : Throughout
the-fall and winter the small caterpillars are hidden within
curious cells that they make in the bark of the trees, es
pecially in- the forks of
the branches: , Thesé lit-
tle burrows are > furnished -
with a‘silker lining, and *
are covered with a sort_
of thatch made hy fasten- *
ing tiny bits of bark to-’
gether with silk. Within:
these hibernating’ cells,
the insects are protected
from most dangers. Early
in spring, the larvee become active and get ready to emerge
from their winter quarters by tearing away a part of the
protective covering. Finally they emerge and attack the
-young buds, burrowing their way into the pith of the short
branches. They thus become twig borers, and often do
great damage.

After a few weeks of this existence, they hide: ‘within the
bits of -curled- bark upon the -trunk and larger branches,
where they change to pupe, generally very “slightly: shel!
tered by a few silken hairs. These pupe shortly change
again into adult moths, that lay their eggs on the bark of
the young twigs. . These eggs soon hatch into tiny larve,
which also become twig borers during ‘the first weeks of
their life, usually upon a tree loaded with'fruit. This brood
of worms lives as‘twig borers for only about three weeks.

They then leave the..twigs and burrow into the green
peaches, entering at the stem end and feeding freely upon .

PEACH-TWIG BORER! WINTER BURROW
Cur OPEN .,

118 FARM FRIENDS AND FARM FOES

the green pulp. Here they continue until they become
- full-grown as larve, often doing an enormous amount of
damage to the peach crop. Finally they emerge from the
fruits and change to pupz on the outside of the peach,
generally in or near the stem cavity. A week later, these
pupz change to moths that deposit their eggs upon the
peaches, and these eggs hatch into worms that also burrow
into the peach fruits, finally maturing and pupating on the
outside of the fruits in the same way that the second
generation did.

A week later, the third brood of moths appears, generally
during the latter part,of August, and these deposit their
eggs upon the bark of the trees. The larve that hatch
from this lot of eggs burrow immediately into the bark
and hollow out the hibernating cells.

There is thus in the extraordinary history of this Peach-
twig Moth a series of three broods of larvz, one of which
is exclusively a borer of bark and twigs, the second of
which is both a twig borer and a fruit worm, and the third
of which, on fruiting trees, is exclusively a fruit worm. It
has been found that the hibernating worms may be de-
stroyed by spraying the trees in spring with a lime, salt,
and sulphur wash, and the injuries may be prevented to a
considerable extent by burying or covering. the piles of
wormy peaches.

THE BUTTERFLIES AND MOTHS IIQ
®

OBSERVATIONS FOR PUPILS
BUTTERFLIES
A

I. Make a list of butterflies that you know by sight. If you have
access to the Butterfly Book or Comstock’s How to know the Butterflies,
you can identify those you see.

2. Keep the caterpillars of some butterflies in a vivarium to see their
changes. You can probably find some one of these : the Cabbage
Worm, Orange-dog, Monarch Butterfly caterpillar on milkweed, Black
Swallow-tail caterpillar on parsley, celery, or parsnip plants or the
Mourning Cloak Butterfly caterpillars on willow, poplars, and elm.

3- Read some of the chapters on Butterflies in Dickerson’s Moths
and Butterflies ; also such of the following as you have access to : —

American Insects, pages 446-454. Nature Biographies, pages I-10, 11-21, 71-88,
Stories of Insect Life, First Series, pages 12-17, 22-27, 37-40.

B

1. Write or tell the story of The Life of a Butterfly. Follow some
such outline as this : —
The laying of the egg.
The hatching of the larva.
The growth of the larva.
The change to the chrysalis.
The change to the butterfly.
The habits of the butterfly.

If the story is written, illustrate it by some sketches of the life stages.

SPHINX MOTHS

1. Late in summer or early in autumn one can generally find larve
of Sphinx Moths by a little searching of these plants : Tomato, grape,
woodbine, or Virginia creeper, purslane, and various trees and shrubs.

‘2. When a Sphinx larva is found, keep it in a vivarium with two.
inches of earth in the bottom. Feed it regularly and keep the vivarium
clean. When it is full grown, it will probably enter the soil to pupate.
Then put the vivarium away in a cool cellar till spring.

3- Read these accounts of Sphinx life histories : —

American Insects, pages 431-439. Moths and Butterflies, pages 224-242.
Stories of Insect Life, Second Series, pages 38-45, 56-62.

\

120 FARM FRIENDS AND FARM FOES
ry

.. BOMBYCINE MOTHS

1. In winter or early spring hunt for cocoons of the giant silkworms
—Cecropia, Promethea, Polyphemus, and other Jarge moths. When
found, keep in a cool place until ‘April or May, then bring. into ne
Schoolfoom to see the moths emerge.

Read the chapters on these moths ‘in Diékerson’ 's Moths and Butter=
flies.

2. In spring you can easily find nests of the Tent Caterpillar. Bring
ie a few larvz and rear in a vivarium.

“Read Mature Biographies, pages 22-34.

"+3. ‘In autumn you can generally find nests’ fi he Fall Web-worm and

cal rear a few of the larva.

Orier’ INSECTS :

ae you do not find Cutworms in your.garden,, you: can probably
haa them under boards along fences or roadsides. Keep a few ina
vivarium, feeding them leaves of clover, and see if you can rear them
successfully. 2.0.0. a

2. If the Bollworm, Corn Worm, o or "Cansato Fruit Worm occur in
your region, see if you can find aid rear’some of the larve.

3. Late in autumn get some nearly full-grown Codling Moth larve in
apples, place in a vivarium, and see if you can get them to spin cocoons.
Keep these to see if you can get the moths from them.

4. Make an estimate .of the..percentage .of ‘apples injured by the
Codling Moth in some orchard. Is the. injury less in orchards sprayed
in spring.than.in those not sprayed ?

5. A little searching of the leaves of trees and shrubs at almost any
time in summer will Teel examples of leaf rollers at work. One
species is common in the leaves of cultivated strawberries. .Another
conspicuous one, is the Wild Cherry. Tent-maker. Rear some of the
larva,into moths. A few small caterpillars can be ue reared in a
covered jelly glass or a glass fruit-jar.

6. Examine the leaves of apple and other trees for leaf miners. They
are generally abundant in summer and early autumn. Break off a twig
with infested leaves and put itina bottle of water to keep the larve alive
until they changé to pupe. ‘Then put the leaf in a jelly glass or other

suitable receptacle, covering with cheesecloth held. in place by a rubber
band.

THE BUTTERFLIES AND MOTHS 121

y. Examine peach trees and peach fruits for the Peach-twig Moths.
See if you can rear the moths.

Read such of these references as your teacher may request : —

The Brown-tail Moth and How to Control It, Farmers’ Bulletin 264. The
Gypsy Moth and How to Control it, Farmers’ Bulletin 275. The Cotton Bollworm,
Farmers’ Bulletin 290. Insects Affecting the Cotton Plant, Farmers’ Bulletin 47. .
The Imported Cabbage Worm, U. S. Bureau of Entomology, Circular 60. The
Peach-tree Borer, U. S. Bureau of Entomology, Circular 54.

"WINTER NEST OF BROWN-TAIL MoTH

CHAPTER IX

The Two-winged Flies

So far as numbers of individuals are. concerned, the
Two-winged Flies of the order Diptera are among the most
abundant of all
insects. These
are distinguished
by the fact that
there is but one
pair of wings, al-
though in most
species there is
a pair of curious
little projections
called halteres
or “balancers”
which represent
the second pair
of. wings. The
flies have com-
plete transformations, and in the larval state commonly ex-
ist as footless maggots. The mouth parts are formed for
sucking, although there are often special modifications for
biting, in connection with the sucking apparatus.

Fortunately, there are comparatively few species of Dip-
tera that are destructive to cultivated crops. Among these
few, however, are some of the most troublesome of all in-
jurious insects, such as the Hessian Fly, the Apple Maggot,

122

LARVA

HESSIAN FLY

PUPARIUM PUPA fica

THEA ROD hy,

THE TWO-WINGED FLIES 123

the Pear Midge, the Clover-seed Midge and certain
other pests.

GaLL GNATS

The Hessian Fly belongs to the family of Gall Gnats
(Cecidomyiidz). These are mosquito-like flies which live
in the larval state upon the growing tissues of plants,
commonly causing an abnormal swelling, which is called a
gall. In the case of the Hessian Fly, the adult insect is a
small creature with smoky brown wings, which appears in
the wheat fields in autumn soon after
the young plants are up. It deposits
eggs upon the leaves, generally a little
above the joints. These eggs shortly
hatch into very. small maggots that
work their way down to the joints and
into the space between the sheath and
the main stalk. Here they remain
and gradually absorb the sap of the
plant. They grow rather slowly, and Husstan FLY
their presence causes a slight swelling Magnified
of the surrounding tissues and prevents
the normal growth of the young wheat plant. After some
weeks, they become full grown in this larval stage, and now
change to what is called the flaxseed condition. To bring
about this change the outer skin of the larva separates from
the skin beneath and gradually hardens into a brown pro-
tective covering. This covering, which looks like a flax-
seed, is commonly said to be the puparium. It corresponds
in a way to the cocoon of a moth in that it serves as a pro-
tection to the insect inside, although its method of formation
is entirely distinct from that by which a cocoon is formed.

The larve remain within these flaxseeds throughout

124 FARM FRIENDS AND .FARM FOES

the winter: In the spring, still inside, they change to pu-
pz, and a little later change again to adult Hessian Flies.
These adults lay eggs for another generation of larve that
attack the wheat in the spring and cause much of it to be
so dwarfed and weakened that the crop is seriously injured.
As arule, this brood of flies seems not.to become mature
until the latter part of the season.

In the case of an insect so minute and so protected
during its earlier stages as the Hessian Fly, many insecti-
cidal methods of controlling it are useless. Consequently,
farmers must resort to agricultural methods if they would
prevent damage by it. One of the most successful of
these methods is that of planting narrow strips of wheat
early in the fall, to attract the flies to lay their eggs, in
order that the main crop of wheat planted later may escape
infestation. The early trap crop.may then be plowed un-
der, so that the eggs and larve present will be destroyed.

Another insect belonging to this same family and also
attacking the wheat is called the Wheat Midge. The
larve in this case are found in the heads of grain rather
than in the stalks, and the damage they do is in the de-
struction or dwarfing of the kernels of wheat. In recent
years this insect seems to have done comparatively little
damage. =

Closely related, both in structure and habits, to the
Wheat Midge is a tiny fly called the Clover-seed Midge.
The flies lay their eggs in the blossom heads of clover,
and the eggs hatch into larvee that develop at the expense
of the young seeds, often causing a serious lessening of-
the crop where clover is grown for seed. The’ injury to
hay crops, however, is very slight.

The Pear Midge is the most destructive insect of this
family that attacks fruit. The eggs are laid in the flower

THE TWO-WINGED FLIES 125

buds and hatch into larve that attack the seed cavities of
the young pears, sometimes doing serious damage. When
fully developed in the larval state, they drop to the ground
where they change to pupz, and emerge soon after as
adult flies. Plowing during the latter part of June and fer-
tilizing with a heavy dressing of
some potash fertilizer is helpful in
-destroying the larva and pupe.

CRANE FLIES
The Crane Flies (Tipulidz) ‘are-
among the largestof the Two-winged
Flies. These insects look like gi-

gantic mosquitoes and may- be’seen APPLE
throughout the summer in pastures MAGGOT
and meadows, as wellasabout houses. MAGNIFIED
In their larval stages some of the Mea Se

commoner Crane Flies feed upon ‘

decaying vegetation and occasionally ‘upon grass roots,
although they are very seldom destructive in America.
These flies show very well the peculiar balancers that rep-
resent the second pair of wings,

Fruit Maccots

Comparatively few Two-winged Flies are injurious to
fruit crops. One of the most destructive of: these is the
‘Apple Maggot or Railroad Worm, a pest that is often very
troublesome in orchards. The adult fly deposits eggs -be-
neath the skins of young apples during the summer. Each
of these eggs soon hatches into a small footless maggot
that tunnels through the fruit in all directions. It continues
the work for five or six weeks, by which time the apple is
pretty well “railroaded ” and ruined for cooking or eating

126 FARM FRIENDS AND FARM FOES

purposes. The injured fruit is likely to fall to the ground.
Then the maggot leaves it and finds ‘shelter in the soil or
in the rubbish at its surface. Here it changes to a pupa,
and remains until the following sea-
son when it emerges as an adult fly.
Thus there is but one brood each
year.

Unfortunately the injuries of this
insect cannot be prevented by spray-
ing. The eggs are deposited beneath
the skin of the fruit out of the reach

CHANNELS OF of insecticides. The best method of

Rene BSR Se checking its increase is that of picking

up or feeding to stock, the fallen apples, so that the worms

‘will be destroyed before they go into the ground. This is.

another insect that indicates the necessity of codperation
in agricultural methods.

A closely related insect, which has done a great deal of
damage in Mexico, is the Orange Maggot or Orange Fruit
Fly. This attacks oranges in very much the same way that
the Apple Maggot attacks apples. When introduced into
an orange-growing locality, it is likely to become a serious
pest. The fact that there was constant danger of its intro-
duction into the orange-growing regions of California has
caused much discussion among horticulturists. It is one of
those pests for which fruit growers should be constantly on
the watch, although, of course, there is no danger of dam-
age from it in regions where the citrous fruits are not
grown.

Root Maacots

There are a number of destructive species of flies be-
longing to the Root-maggot group (Anthomyiine). In

THE TWO-WINGED FLIES 127

the adult state, these flies bear a general resemblance to
the familiar house fly, although commonly they are some-
what smaller and are easily distinguished by experts. The
Cabbage Maggot, which is also knownas the Radish Maggot,
and the Turnip Maggot, is a good example of these insects.
The adult flies appear in the cabbage fields when the plants
are set out, and deposit their <2

small white eggs about the
base of the stalks. A few
days later these eggs hatch
into tiny, whitish, footless
maggots that attack with
theirrasping mouth parts the
outer tissues of the roots.
They continue to feed and
grow for three or four weeks,
commonly causing the death
of the plant on account of
the destruction of the sec-
ondary roots or of the girdling of the primary root. By
the end of this period they become full-grown as larve
and change to pupe.

This process of changing to the pupa state in a large
proportion of the two-winged flies differs from that of most
other insects. The insects are unable to spin cocoons, but
they get the protection of an outward covering in this way:
The skin, which in most insects is cast off when the larva
changes to a pupa, in these maggots gradually hardens and
becomes brownish in color. It does not split open any-
where, so that it forms a covering to the insect, inside which
the latter becomes a pupa after this outer skin, which is
now called the puparium, has hardened. Itremains within
this puparium about a fortnight when it again changes into

428 FARM FRIENDS AND FARM FOES

an adult fly that breaks through the outer shell and emerges
tothe sunlight. The formation of the puparium takes
place in the soil an inch or less below the surface.

As the common names already mentioned indicate, this
little pest is by no means confined to cabbage; it attacks
radishes and turnips, as well as a variety of wild plants be-
longing to the mustard family. There are several broods
each year. The insects commonly pass the winter as
adult flies, although a certain proportion of them hiber-
nate also in the puparia.

The Cabbage Maggot has been one of the most trouble-
some insects that the gardener has to fight. It is often
very destructive in seed beds where the young cabbages
for late planting are being grown. Recent experiments
have shown that the best way of preventing this injury is
to surround the seed beds with a broad frame twelve inches
high, tacking cheesecloth over the frame. If the frame is
so tight that no flies can enter, the seedlings will grow
rapidly and be free from i injury not only by these maggots,
but also by the flea beetles which are often very destructive
to such seedlings. When the plants are large enough to
set out, the cloth should be removed and full exposure to
the sun be given for at least a week. This is to harden
the seedlings so that they may be transplanted successfully.

The Onion Maggot is another vexatious insect belong-
ing’ to this family, which is very similar to the Cabbage
Maggot in its appearance, habits, and life history. It
attacks onions, especially the young ‘plants, and in many
regions is the most destructive enemy of this’ crop.

Another group of insects’ belonging to this same family
attacks the leaves of cultivated crops ‘instead of the roots.
The adult flies deposit their whitish eggs upon the surface
of the leaves of beets, spinach, and other succulent plants.

THE TWO-WINGED FLIES 129

These eggs very soon hatch into small maggots that bur-
row through the outer skin of the leaf and begin to de-
velop as miners of the interior tissue. They thus become
true leaf miners, and their presence is soon shown by the
difference in the color of the surface of the leaf. By
holding such a leaf up to the light, the maggot inside can
generally be seen. These larve continue to develop
within the leaf for a few weeks before they become full
grown, and by this time a single ‘larva will ‘have injured
a large portion of a leaf. When full grown they burrow
through the outer skin and drop to the ground, where they
change to pupz slightly below the surface. A little later
they again change to adult flies. There appear to be sev-
eral broods each year.

As is the‘case with the root maggots, these leaf- mining
species are by no means confined to cultivated crops. They
may very: commonly be found:at work upon wild plants, such
as the white pigweed or some of the commoner docks.

OBSERVATIONS FOR PUPILS
HESSIAN FLY

1. If you live in a.wheat-growing region, learn what you can about
local damage by the Hessian Fly. If not now injurious, ask your farmer
friends if it has been in the past.

2. Examine wheat fields to see if you find injured plants. If so, look
for the larve or “ flaxseeds” of this insect.

3. If found, place the flaxseeds in a glass dish to see if you can rear
the flies.

4. Read the account of the Hessian Fly in Circular. 70, Bureau of
Entomology, U. S. Department of Agriculture.

AprpLE MaGGoT

1. If you live in an apple region, determine whether this insect is pres-
ent. Examine windfalls of early varieties to see if the characteristic bur-
rows in the pulp are present.

130 FARM FRIENDS AND FARM FOES

2. If the pest is at work, gather some injured apples, and place in a
box with an inch or two of soil.in the bottom. The larve will probably
enter the soil, and you will be able to rear the flies.

Root MaGGots

1. What crops in your region are injured by root maggots ?

2. Get some:of the maggots from roots of radish, turnip, cabbage, or
onion. Keep in moist earth and see the change to paparia and later to
flies.

3. Try to find eggs, larva, and puparia about the roots of injured
plants.

LEAF-MINING MAGGOTS

1. Examine the leaves of beets, spinach, dock, and pigweed to find
discolored areas. If made by the leaf miners, the larvae may readily be
seen by holding the leaf up to the light or by opening the mine.

2. Place some of the leaves that have larve of good size in a bottle
of water. Set in a vivarium with earth in the bottom. The larvae will
probably pupate in the earth and later change to flies.

THE STORY

Tell or write the life story of one of these injurious flies that you know
most about. Illustrate by drawings on blackboard or paper. Perhaps
this outline will help you : —

Size, color, and appearance of the fly.
When and where the flies are found.
When and where the eggs are laid.

Size and color of the eggs.

How soon the eggs hatch.

What the larve feed on.

How long the larve live.

Where the larve change to pupz.

How long before the pupe change to flies.

CHAPTER X

The Beetles : Order Coleoptera

THE great order of sheath-winged insects to which the
beetles belong is one of the largest and most important
groups of insects.
Most of its mem-
bers have har-
dened wing cov-
ers over the true
wings, and the
whole outer sur-
face of the body

is hardened in E WHITE GRUB
a characteristic or
manner. The MAY BEETLE
larvee are grubs
that va tl

at vary greatly Egg

in form and hab-
its, and the pupa O

is a quiet stage in

which the insect does not eat or move about.

' The feeding habits of the adult beetles are exceedingly
varied; many feed upon plant tissues; many others upon
animals, alive or dead. Among the plant-feeding groups
are some of the most troublesome, injurious insects, while
among the animal-feeding forms are some very beneficial

insects.
131

132 FARM FRIENDS AND FARM FOES

LAMELLICORN BEETLES

Only a few of the great number of beetle families can
be considered in these pages. One of the most important
of these is the great group of Lamellicorn Beetles (Scara-
bzids). These have curious enlargements on the ends of

the feelers or antennz, each swollen part
consisting of a number of thin plates rest-
ing upon one another. The May Beetle is
a typical example of this group.
In both its adult and its larval condition,
the May Beetle or June: Bug is only too
‘familiar to most people. From the advent
of the first warm days in spring until sum-
LaMELLICORN mer is well along, the brown beetles are
peoine likely to be seen flying about trees or lights
or crawling along the surface of the ground. These beetles
feed freely upon the leaves of a great variety of fruit
and shade trees, sometimes doing much injury in this way.
They deposit their eggs about the bases of grass stems,
and the eggs soon hatch es
into small larvee that feed
upon the roots of grasses
and gradually develop ;
into the well-known white |
grubs, which are almost
always to be found in
abundance when grass
lands are plowed. It is
believed that these white
grubs require at least
three years to complete their development, becoming large
toward the end of this period and able to destroy the roots

i 3

POTATO INJURED BY WHITE GRUB
Reduced

THE BEETLES: ORDER COLEOPTERA 133

of many plants. They finally change to pupz in earthen
cells and generally change again to adult beetles in late
summer or autumn. The beetles remain in the soil until
the following spring.

The white grubs have many enemies among birds and
wild animals, such as foxes and skunks. These natural
enemies are the most potent means of keeping them in
check in regions where the grubs become destructive.
The killing of the adult beetles by attracting to lights. or
collecting in other ways will often become necessary.
This is a case, however, where concerted action by. all the
farmers of the community is exceedingly desirable.

Another vexatious member of this great family of bee-
tles is the so-called Rose Chafer or Rose Bug. This is
one of the most destructive enemies of fruits. The
brown ‘beetles appear in vast swarms early in sum-
mer, when the wild roses are in blossom. They
feed upon the leaves and flowers of a great vari-
ety of fruit and ornamental plants, such as apples, _RosE
pears, plums, ‘peaches, roses, raspberries, straw- a
berries, blackberries, and grapes. They often do serious
damage to the grape crop by eating the blossoms. The
beetles remain active two or three weeks. During the
‘latter part of this period, the eggs for a new brood are
laid in the ground. The insect chooses for this purpose
open fields and meadows having a sandy soil. About a
fortnight later, the eggs hatch into small grubs that feed
upon roots of grasses. These grubs become full grown, or
nearly so, during the summer and early autumn. On the
approach of winter, they burrow deeper, and the following
spring again work their way upward near the surface.
Here in earthen cells they change to pupz, and emerge a
month later as fully developed beetles.

134 FARM FRIENDS AND FARM FOES

This is a difficult pest to contend against. The most
effective method as yet employed is the laborious one of
picking the beetles by hand and destroying them.

Cuiick BEETLES

Every farmer’s boy is familiar with the slender, yellow
Wireworms so commonly found when grass lands are
plowed. These insects feed upon the roots of grasses and
grains. They often become seriously destructive to crops
planted upon ground that has been in
sod for several years. When fully de-
veloped in their larval stage, these Wire-
worms change to pupz within oval cells
in the soil and a few weeks later change
again into adult Click Beetles or Elaters.
They usually remain, however, within
the cells until the following spring, the
tissues gradually hardening until they
become very firm and hard even for a
beetle. Then the adults come forth and
fly freely about, often visiting various
flowers from which they lap up thenectar. These Elaters
are often called, Snapping Beetles from the fact that when
placed upon their backs, they snap upward, apparently in
an effort to regain the crawling position. It is supposed
that the eggs are laid about the roots of grasses.

The Wireworms are very difficult to destroy by any form
of insecticides. The most desirable method of checking
their increase seems to be that of fall plowing, which breaks
up the pupal cells and exposes the beetles to destruction
by weather conditions through the winter.

EYED ELATER

THE BEETLES: ORDER COLEOPTERA 135

Lear BEETLES

One of the most generally destructive families of beetles
is that of the Leaf Beetles (Chrysomelidz). Asa rule, these
are elongated or roundish beetles, having jaws especially
adapted for feeding upon leaves. Their larve, for the
most part, are short, thick grubs, with well-de-
veloped thoracic legs. They feed in both the
larval and adult states upon a great variety of
wild and cultivated plants, and often become seri-
ously destructive to the latter.

No member of this great family is so generally
and unfavorably known as the Colorado Potato Beetle.
Originally a native of the Rocky Mountain region, where it
fed upon a wild species of Solanum, — the genus to which
the common potato belongs, —it started eastward as soon
as the settlers’ garden patches connected its home with the
Atlantic states by means of a practically continuous potato
field. Then it boarded transatlantic steamships and stole
a passage to Europe,
where it gained a de-
cided foothold before re-
ceiving the attention it
deserved.

The various stages
of the Colorado Potato
Beetle are. shown in
the accompanying pic-
tures. The brown-striped
beetles deposit the or-
ange-colored eggs in masses upon the leaves. These eggs
shortly hatch into the curious brown grublike larvee, which
feed upon the tissues of the leaves and cast their skins

LEAF
BEETLE

COLORADO POTATO-BEETLE -

136 FARM FRIENDS AND FARM FOES

occasionally as they increase in size. In three or four
weeks, they become full-grown as larve. Then they make
their way into the soil and change to pupa. Ten days
later they change again to adult beetles. The number of
broods varies with the latitude, there being from two to
four each year. The eggs are eaten by lady-bird beetles,
and the adults are devoured by certain birds, notably the
grosbeaks and the bobwhite. Both larve and adults are
readily killed by spraying or dusting the potato vines with
arsenical poisons.

Another leaf beetle that is very often destructive is the
Asparagus Beetle. This is one of those numerous pests
that have been ‘introduced into America from Europe. It
is not yet generally distributed, but is constantly being in-
troduced into new localities where asparagus is grown.
The adult beetle is rather slender, less than half an inch
long, and is easily recognized by the brilliant combination
of black marked with red or yellow. When such a beetle
is found feeding upon asparagus, it is pretty certain to be
this Asparagus Beetle. If there are twelve spots, however,
it is probably the less common Twelve-spotted Aspar-
agus Beetle, which has also been lately introduced from
Europe.

The eggs of the common Asparagus Beetle are deposited
upon the leaves and stems of the plants,and soon hatch
into small grublike larvee that feed freely upon the leaves,
often doing great damage to young plantations. These
larvae pupate in the ground and soon emerge again as
adult beetles.

Various methods of checking Asparagus Beetles have
been found successful on young plantations. Dusting the
vines when they are wet with dew with fresh, dry air-slaked
lime has been found to kill the larve.. On older planta-

THE BEETLES: ORDER COLEOPTERA 137

tions, which are being cut over, the leaving of a few stalks
as trap plants to attract the adult beetles when they lay
their eggs has been found effective. These trap plants,
of course, are to be destroyed often enough to prevent the
eggs from hatching.

A much more familiar and widely distributed leaf beetle
is the common Striped Cucumber Beetle, which is found
practically everywhere that cucumbers, melons, squashes,
or related plants are grown. These insects pass the
winter as adults under such shelter as they may find, and
in spring feed ravenously upon the young cucumber or
other plants. They also deposit their eggs about the
roots of these plants, and the eggs shortly hatch into
slender larvz that feed upon the roots. In this way, the
beetles not only threaten the crop in their adult state, but
they often do a more serious, though less recognized,
damage in their larval state. These are among the most
difficult of all pests to keep in check. A few hills may be
covered with netting or cloth. The liberal use of refuse
tobacco powder is generally also an efficient protection.
The complete destruction of all squash, cucumber, melon,
and pumpkin vines as soon as the crop is gathered is a
very desirable preventive.measure. If these are left, the
adult beetles find abundant food up to the time they go
into their hibernating quarters, and consequently are in
better condition to survive the winter.

A closely related insect, which at times has been ex-
ceedingly destructive, is the Northern:Corn Rootworm.
This is a small beetle, about the size of the Cucumber
Beetle, but of 2 uniform pale green color. In the larval
state it feeds upon the roots of corn and so weakens. the
plants that the development of the crop is greatly
checked, ‘The larvae change to the pupa state and

138 FARM FRIENDS AND FARM FOES

emerge as beetles during the later part of summer or
early in autumn.

These beetles then deposit eggs in the same, fields in
which they were developed and the eggs remain unhatched
until the following spring. If corn is then planted, the
larve feed again upon the roots and repeat the injury of
the season before, but if the field is planted to some other
crop upon which the larve are unable to develop, the in-
sects will die and the damage will be prevented. Conse-
quently this Corn Rootworm has been a blessing in disguise,
for it has compelled those farmers who were depleting the
fertility of their land by a constant succession of corn
crops, to adopt a system of rotation. The discovery of
the life history of the Northern Corn Rootworm and the
pointing out of the fact that its injuries may be prevented
by the rotation of crops is one of the most notable ex-
amples of the benefits to be derived from: scientific ento-
mology. The credit for it is due to Dr. S. A. Forbes, the
state entomologist of Tlinois.

The insect known in many of the Northern states as
the Twelve-spotted Cucumber Beetle, is also known in the
South as the Southern Corn Rootworm. Throughout its
range, it feeds as an adult upon succulent leaves, and
probably develops as a larva upon a considerable variety
of plant roots. In Kentucky and some other Southern
states it causes much damage to corn crops. Its Southern
life history is briefly this: The adult beetles hibernate at
the surface of the’soil or just below, in fields of clover, al-
falfa, and other crops. They come forth early in spring,
and as soon as the young corn plants are well started, they
deposit their eggs about the roots. The eggs soon hatch
into larvae that become full grown early in summer, chang-
ing to pupz and soon again into adults which appear

THE BEETLES: ORDER COLEOPTERA 139

about midsummer. In a short time, these lay eggs for a
second brood of larvz that develop into adult beetles in
autumn. These beetles hibernate until the following
spring. There are thus two broods of larvze each season.

The fact that this Southern Corn Rootworm hibernates
in the adult condition and that the beetles can fly freely
from place to place, shows at once that this pest cannot be
checked by the simple method of rotation that serves the
purpose in the case of the Northern Corn Rootworm.
Rotation of crops will be helpful, especially if care is
taken not to plant to corn those fields to which the adult
beetles were attracted the previous autumn by an abun-
dant supply of succulent food.

FLEA BEETLES

There are several species of Flea Beetles which also be-
long to this leaf-beetle family. Some of the larger Flea
Beetles have a life history similar to that of the Asparagus
Beetle and the Colorado Potato Beetle, both larve and
adults feeding upon the foliage of the food plants. The
Grape Flea Beetle is an excellent example of
these insects. It often becomes a destructive
pest in vineyard regions.

The smaller Flea Beetles, however, are moré
universally distributed and affect a great vari-
ety of cultivated crops. These are tiny beetles ;

. . “4: FLEA BEETLE
which are able to jump great distances when ~ yasnifiea
disturbed, and which are only too commonly
found upon potato, tomato, cabbage, and other garden
plants. They not only do decided damage by eating out
the surface of the foliage, but they afford an easy ingress
for the germinating spores of many kinds of fungous dis-
eases. In their larval state, some, at least, of these smaller

140 FARM FRIENDS AND FARM FOES

Flea Beetles live as miners in the leaves and stems of va-
rious plants. Spraying with Bordeaux mixture is one of
the best methods of preventing their injuries.

LonGc-HORN BEETLES

The so-called Long-horn Beetles (Cerambycide) form
one of the most sa a groups of the order. The adults
have cylindrical bodies, frequent-
ly of large size, with feelers or an-
tennz generally as long as the
bodies or longer. These beetles
deposit their eggs upon the bark
or wood of a great variety of trees
and shrubs, and the. eggs hatch
into footless grubs that burrow
into the bark or wood of the host
| plant. Some of the most destruc-
ROUND-HEADED Appie-tree tive fruit-tree pests belong to this

BORERS family, a notable example being
Beetle and Pupa the Round-headed Appletree
Borer, which is often very injurious in apple orchards.

The Locust Borer is one of the most abundant as well
as most beautiful of the beetles belonging to this family.
It is attractively colored, being brown or
black, marked and striped with lines of
light yellow. This beetle is very abun-
dant in late summer and early autumn
upon the flowers of goldenrod, which it
visits in search of pollen. The life his-
tory briefly summarized is this: The
beetles found in August or September
deposit their eggs one at a time in the incsaeneeae
crevices of the bark of the common or BEETLE

THE BEETLES: ORDER COLEOPTERA 141

black locust trees. In about ten days these eggs hatch
into tiny larve that excavate slight cells in the bark; they
remain in these cells throughout the winter. Soon after
the sap begins to flow the following spring, the larvze be-
come active and begin to burrow through the bark into the
wood. The burrows that they make are commonly not
very long and are enlarged as the insects increase in size.
The larvee become full grown in a few months, and change
to pup within their burrows about midsummer. A little
later they change again to adult beetles that come forth to
feed upon goldenrod flowers and deposit eggs for another
generation of borers.

The characteristic larvee of various wood-boring beetles
are very often to be seen when firewood is split up, dropping
out of the cylindrical chambers they have burrowed in the
wood. They may also frequently be found beneath the
bark-of fallen trees or in the partially decayed wood of
dead stumps. Some species are much more destructive
than others, but in general their life histories are quite simi-
lar. The Pine Sawyer is a large species that breeds in
dead pine trees and often causes losses of millions of
dollars in asingle year. The Oak Twig Pruner is another
widespread pest; it may commonly be found in fallen twigs
under oak trees.

CURCULIOS AND OTHER SNOUT BEETLES

Most farmers’ boys know how difficult it is to grow
plums. From the time the fruit is half grown until it is
ripe it continues to fall to the ground, and when examined
is found to be wormy and unfit to eat. This worminess
is generally due to the insect known as the Plum Curculio,
a small, hard-shelled, brownish beetle, which appears among
the plum trees in spring. It. gnaws holes in the leaves,

142 FARM FRIENDS AND FARM FOES

the flowers, and the green plums to satisfy its hunger. The
females also cut crescent-shaped holes in the skin of the
young fruits and deposit an egg beneath each of the cres-
cent marks. In from
three to seven days these
eggs hatch into little
grubs that feed upon the
pulp of the fruit, gradu-
ally working toward the
pit. They become full-

=A Food Puncture
ju

Larva-—-----

me sey grown in two or three
CURCULIO weeks. The infested

plums by this time are
so injured that they generally fall to the ground. Then
the larvz leave the fruit, and burrow into the soil about an
inch, where they change to pupz. Three or four weeks
later, they change again and come forth as perfect beetles.
There is but one brood of the worms
each season. The adult beetles hiber-
nate under such shelter as they can find
at the surface of the soil.

The Plum Curculio is by no meansan _2
unmixed evil. In many localities it per- #
forms an essential service by thinning
the plums, thus saving the fruit grower
‘much expense. Besides plums, it attacks
peaches, cherries, apricots, nectarines,
apples, and pears. In the case of the
last two a large proportion of the larve
appear to be unable to develop in the
green fruit, but the injuries by the adult beetles often cause
the fruits to be dwarfed and gnarly.

There are several natural enemies of the Plum Curculio.

STRAWBERRY
WEEVIL

THE BEETLES: ORDER COLEOPTERA 143

One of the most efficient of these is the tiny fly that depos-
its its eggs in the eggs ofthe Curculio. The fly eggs hatch
into maggots that destroy the Curculio eggs and mature in
a few days into other flies like the parent parasites. Conse-
quently several generations of these egg parasites may
follow one another through the season.

There are also other parasites that attack peacH
the Curculio larve. The fluctuations in
the abundance of the Curculios from sea-
son to season is probably due chiefly to
these parasitic enemies.

It has been found that even in large
orchards the injuries of the Plum Cur-
culio may be prevented to a great ex-
tent by spraying the trees with arsenical
poisons, beginning just after the blossoms
have fallen. The adult beetles feeding
upon the leaves and young fruit are thus
poisoned. For a few trees this method is not always so °
successful, and it is necessary to adopt the jarring device.
When a branch upon which the adult beetles are resting is
shaken, the insects fall to the ground, remaining quiet for
some time afterward. By holding sheets stretched upon
wooden. frames under the trees and then shaking the latter,
the beetles may be collected in numbers. It is also often
advisable to supplement the spraying, even in large
orchards, by the jarring process. The destruction of the
plums as fast as they fall and the cultivation of the soil
beneath. the trees during the summer are also helpful
measures.

A group of Snout Beetles that at times has proved
very destructive in the great corn-growing regions of the
Central West, is that of the Billbugs. These are compara-

INJURED BY
CURCULIO

144 FARM FRIENDS AND FARM FOES

tively large insects, having hard bodies with long snouts, on
the ends of which are well-developed jaws by means of
which they can burrow through young cornstalks very
quickly. The adult beetles feed upon the tissues of these
stalks, greatly weakening the plant when they burrow
through it. In the case of a typical species, the insect
hibernates in the adult state, and attacks the young corn
soon after it comes up. The eggs are laid in early sum-
mer, commonly about the bulbs of timothy and perhaps
other plants, and the larvae burrow into these bulbs and there
develop. They grow rapidly and become mature beetles
late in summer or early in autumn.

Some of the best-known species of Billbugs develop as
larvae in sedges or rushes of various kinds. Practically all
of them appear to breed chiefly on low lands where sedges
are likely to abound. The cornfields often injured are
those upon or near such lands. Fall plowing is an efficient
preventive of injury by these pests.

Cotron BoLL WEEVIL

The Cotton Boll Weevil has attracted more attention
during recent years than almost any other destructive
insect. Migrating into
Texas from Mexico about
the year 1890, this pest
has gradually spread to-
MEXICAN ward the north and east

and threatens to become
COTTON BOLL destructive almost every-
WEEVIL where that cotton is

PUPA f
grown. Within about a

EGG dozen years of its intro-
) duction, when it was still

THE BEETLES: ORDER COLEOPTERA 145

largely confined within the borders of Texas, the loss to
the cotton crop in one year due to this insect was esti-
mated at $15,000,000 by Dr. L. O. Howard, entomologist
of the United States Department of Agriculture. The
possible annual loss to the cotton planters of the South
in case the pest should be-
come generally distributed,
has been estimated at
£250,000,000. Conse-
quently it is not strange
that this insect hasreceived
a great deal of attention
from the national and state
governments, and_ that
strenuous efforts are being
made to destroy it where
it now exists, and to pre-
vent its introduction into
new localities.

Briefly stated, the life
history of the Boll Weevil is this: The adult snout beetles
pass the winter in a great variety of shelters, in or near
the cotton fields. In spring they come forth from their
hibernating quarters and attack the young plants, feeding
upon the buds, in which they make small round holes. In
some of these holes are deposited eggs that soon hatch
into whitish, footless grubs that feed upon the interior of
the buds, destroying the blossoms and thus greatly injuring’
the prospects of the crop. These larve grow rapidly and
in a few weeks become mature, so far as this stage is con-
cerned. They then change to pupz still-within the shelter
of the bud, and a little later change to adult beetles. They
gnaw their way out and soon deposit eggs for a second

INFESTED COTTON SQUARE

146 FARM FRIENDS AND FARM FOES

brood of larvz. There are several broods during the sea-
son, the larvz being able in the hot weather of midsummer
to become full grown, so far as the larval stage alone is
concerned, in one week. The later broods develop within
the cotton bolls and thus cause a vast amount of damage.

The Boll Weevils continue to multiply through the fall
upon any plants that are still present in the fields, and those
which hibernate most successfully are the ones that develop
latest in the season. Consequently, as a result of many
careful observations and experiments, it is pretty certainly
established that the most effective practical-remedy for the
insect is to pull up and burn all the cotton plants present
in the fields in autumn. This may usually be done by cut-
ting off the roots with a plow and then at once gathering
the plants by hand and piling them in windrows where they
will rapidly dry out, and in about two weeks may be burned.
The addition of a little crude oil is sometimes desirable to
insure the complete destruction of all the stalks. In an in-
teresting experiment conducted by the Department of Agri-
culture, an isolated cotton-growing region of about four hun-
dred acres was thus treated in autumn, with the result that
the beetles were nearly all destroyed and the following season
the amount of damage done by them was insignificant.

Fall plowing is often a desirable procedure in cotton
culture whether the Boll Weevils are present or not, and so
it seems that this pest, like so many others, will bring about
an improvement in agricultural methods.

OBSERVATIONS FOR PUPILS
PLum CuRCULIO
A

1. Pickup some green plums from beneath the trees. Can you find any
of the crescent-shaped marks where the Curculios have laid their

THE BEETLES: ORDER COLEOPTERA 147

eggs? Can you find any holes where the Curculios have been simply
feeding?

2. Cut open some of the fallen plums. Can you find eggs or larve
in the green pulp? Can you trace the holes made by the larve in bur-
rowing through the pulp?

3. Place a few freshly fallen plums on two or three inches of garden
soil in the bottom of a glass jar or a wooden box. A week later see if
you can find any larve or pup@ in the soil. Leave some of them and
see if you can rear the adult beetles.

4. Hold a sheet or a large piece of paper under a plum tree and jar
the limbs above. See if you can get any of the Curculios in this way.
You may know them by their hard shells and curious snouts. Place a
few of them under a bell glass with a branch of green plums held in a
bottle of water. Watch the beetles eating and ovipositing.

5. Examine peaches, cherries, apples, and pears to find similar injuries
of the Curculios. Do you find any live Curculio larve in green apples
and pears?

B

1. Write or tell a little story with this title: The Life of the Plum
Curculio. Follow this outline : —
The beetle in winter.
The beetle in spring.
The laying of the egg.
The hatching of the egg.
The growth of the larva.
The change to the pupa.
The change to the adult.
Remedies for injuries by Curculios.

2. Make some or all of these drawings: A plum showing feeding
holes and crescent holes; a section of an injured plum with larva in-
side; an apple or a peach injured by Curculios.

3. Read Circular 73, U. S. Bureau of Entomology.

May BEETLES

1. Have you ever seen white grubs in the soil turned over in plow-
ing or spading ?

2. Are these grubs more likely to be found in sod land than in that
which has been cultivated for several years ?

148 FARM FRIENDS AND FARM FOES

3. Did you ever see the fully developed beetles in freshly plowed
ground? At what seasons are they found ?

4. Collect some of the beetles that fly about during the evenings in
May or June. Kill them in a cyanide bottle. Study their structure.
How do they differ from grasshoppers ?

5. When the beetles are thick, try putting a lantern outdoors over a
tub of water with a bit of kerosene on top. See how many beetles are
killed in this way. Write or tell the story of the life history of the
May Beetle. Make some drawings to illustrate the story.

CoTTON BOLL WEEVIL

1. If you live in a cotton-growing region, find out whether the Boll
Weevil is present. If so, learn how long since it first appeared in your
locality.

2. See what stages of the weevils you can find.

3. Look especially in cotton fields in fall to see whether any of the
pests are hibernating there. ;

4. Learn what methods of preventing injury by weevils have been
adopted by the cotton growers.

5. Write a little story with this title: What I Know about Boll
Weevils. Illustrate it with drawings.

6. Read the account of the Cotton Boll Weevil in Farmers’ Bulletin
344.

RosE CHAFER

1. At what season do you find the first Rose Chafers ?

2. What plants do they attack most seriously in your region?

3. Are there extensive sandy lands near, where the larve may de-
velop ?

4. Why is it probable that few birds would eat these beetles?

OTHER BEETLES
Read such of the following references as your teacher directs : —

The Corn Rootworms, Circular 54, U. S. Bureau of Entomology. The
Clover Root-borer, Circular 67, U. S. Bureau of Entomology. The Colorado
Potato Beetle, Circular 87, U.S. Bureau of Entomology. The Fruit-tree Bark-
beetle, Circular 29, U. S. Bureau of Entomology. The Larger Apple-tree
Borers, Circular 32, U.S. Bureau of Entomology.

CHAPTER XI

Hymenoptera: the Ants, Bees, Wasps, and Sawflies

THE ants, bees, wasps, and sawflies, with other related in-
sects, form one of the most characteristic of all the orders.
Itis called Hymenoptera, and its members may be known by
the fact that they pass through complete transformations,
and that the adults generally havé four more or less trans-
parent membranous wings, of which the front pair is the

‘larger. The mouth parts are formed for biting, but there
is commonly present also a tongue by means of which the
insects can suck or lap up liquids. In the case of the
higher members of this order, the larvee feed upon a special
food prepared by the adults.

SAWFLIES

As very few of the Hymenoptera feed on plant tissues,
a comparatively limited number of injurious species are
found in the order. Of these the most im-
portant belong to the great family of Sawflies
(Tenthredinidz) which are characterized by ©
having an ovipositor by means of which the.
insects are able to cut holes in vegetable tis-
sues for the insertion of their eggs. The
eggs are commonly laid within such cavities, but sometimes
they are deposited along the outer surface of leaf or stem.
They soon hatch into caterpillar-like larva, commonly
called false caterpillars or slugs, which feed upon the foli-
age and finally spin cocoons within which they change to

49

CHERRY Saw-
FLY. Magnified

150 FARM FRIENDS AND FARM FOES

pupz, and change again later into adult sawflies. The
sawfly larve have three pairs of true legs and six to eight .
pairs of prolegs. Most of them have the abdomen curved
inward in the curious way shown in the
picture of the Willow Sawfly larva.

The Common Currant Worm is one of
the most familiar of the sawflies, and its
life history fairly illustrates that of many
related species. The small whitish glassy
eggs are deposited in spring upon the
principal veins of the under side of the
lower leaves of currants and gooseberries.
In about ten days these eggs hatch into
small whitish grubs or larvze that eat cir-
cular holes in the leaves. After a few
days they cast their skins or molt—a
process that is repeated several times dur-
ing the next six weeks. In color they
change from whitish to plain green, but
soon become dotted with black, a color condition that con-
tinues until the last molt, when they change to light green
with a little yellow on some parts of the body. As they
grow older the injury to the leaves increases, and in severe
attacks the bushes are completely defoliated.

When fully grown in the larval stage, the Currant Worms
descend to the ground, seeking shelter beneath the leaves
and rubbish. There they spin tough, brown, silken cocoons
within which they change to pupz. A short time later
they again change to four-winged flies. These come forth
early in summer and deposit eggs for a second brood of
larvee, most of which pass the following winter within their
cocoons.

The eggs of the Currant Worm, small as they are, are

WILLOW SAWFLY
LARVA

ANTS, BEES, AND WASPS ISI

infested by a tiny parasite that develops inthem. An ex-
ceedingly minute fly deposits its eggs within the eggs of
the Currant Worm — one in each. The former hatch into
tiny footless larve that develop at the expense of the
material of the Currant Worm egg. Finally these larve
pupate and later change to tiny adult flies.

This Currant Worm was originally a native of Europe,
having been introduced into America many years ago. Its
injuries may be prevented by spraying or dusting the
bushes with hellebore when the larve are young. It should
not be applied when the fruit is ripening.

In addition to the Currant Worm, there are a number
of other insects belonging to this group. A very similar
species feeds upon the foliage of raspberries and is called
the Raspberry Sawfly. Another feeds upon strawberry
leaves and is called the Strawberry Sawfly. Still an-
other, which is an unusually large species, feeds upon
willow and is called the Willow Sawfly. A very character-
istic form often injures grape leaves and is sometimes
called the Grape Slug.

Two similar and characteristic sawfly larvae are found
upon pears, plums, and cherries, and upon roses. These
have in their younger stages curious slimy skins and eat
only the surface of the leaves, causing a characteristic and
easily recognized injury. The presence of this slimy coat-
ing enables one to killthem readily by applying almost any
fine powder, such as road dust or air-slaked lime to the af-
fected foliage. The particles will adhere to the larvee and
eventually cause their death. ;

Most of these false caterpillars are marked in colors of
striking contrast which indicate that they have some method
of defense from birds. They are thus examples of what
the naturalists call warning coloration, and they seem to

152 FARM FRIENDS AND FARM FOES

be comparatively little injured by birds. All of them, how-
ever,‘are easily destroyed by spraying with arsenical poisons
or even with insect powder or hellebore.

FourR-WINGED GALLFLIES

The next most important group of injurious insects be-
longing to the Hymenoptera is that of the Gallflies (Cyni-
pide). There are many species of these insects which
affect almost every sort of tree, shrub, and herbaceous
plant, but comparatively few of them are destructive to
cultivated crops.

One of the most familiar of these injurious insects is the
species that makes its home in' blackberry canes, causing a
large abnormal swelling upon the cane which is commonly
called the pithy Blackberry Gall. The small four-winged
Gallfly deposits its eggs in the growing stem, a large
number of eggs being placed near together. These hatch
into tiny larve which bring about an abnormal growth of
the blackberry tissues that eventually takes the form of the
curious gall. If you cut one of these open, you are likely
to find a great many little cells in which the larve are
living. They finally transform to pupz within these cells,
and emerge later as adult flies. The cutting and burning
of all affected stalks in winter will help to check the increase
of these insects.

A great many forms of Gall insects may be found at al-
most any time upon the willows and the oaks. The familiar
oak apples are excellent examples of the sort of abnormal
vegetation growth caused by the Gallflies.

CuHatcip Fires

The great family of small parasitic flies, called the Chalcid
family, consists for the most part of insects that live in their

ANTS, BEES, AND WASPS 153

larval stages upon other insects. A very few, however,
develop at the expense of vegetable tissues. The Wheat
Jointworm, of the genus Isosoma, is the most notable ex-
ample of the latter, The adult of this is a small fly
which deposits its eggs in the wheat stem at or near a joint.
The egg hatches into a tiny footless larva, which absorbs
the sap of the plant, causing the tissue to harden and the
growth of the wheat to be injured. The larva finally ma-
tures into a pupa and again into an adult fly. When it is
present in large numbers, it may seriously injure the
wheat crop, but it is comparatively easily destroyed by any
procedure that causes the destruction of the stalks contain-
ing larve or pupe. The burning of the wheat stubble is
one effective remedial measure.

OBSERVATIONS FOR PUPILS

IMPORTED CURRANT WORM

1. In spring or summer examine the leaves of currant and gooseberry
bushes carefully for the eggs upon the under side of the midrib and
secondary veins. Do you suppose all the eggs on one leaf are deposited
by one sawfly ?

2. If you find any leaves with eggs upon them, place the leaf in a
vivarium with the stem inserted in a bottle of water. Watch for the
hatching of the larva, and feed them fresh leaves from day to day.

3- Look at the lower leaves on the currant bushes to find some with
round holes in them. Are there any currant worms at work on such
leaves ?

4. Raise a few currant worms in a jelly glass or other vivarium.
Note the changes of color from time to time. Can you find the cast
skins after molting ? Do the caterpillars stop eating and rest before and
after molting? Where does the skin split open before it is cast off ?

5. Examine carefully the legs on a good-sized currant worm. Are
they all alike? Which are more pointed? How many legs in all?
Watch the insect as it crawls, and notice how the legs are used.

6. When the larve spin their cocoons, notice the texture of these.

154 FARM FRIENDS AND FARM FOES

Is it like the texture of a moth cocoon? Are they water-tight ? Can
you find any cocoons out of doors beneath infested currant bushes ?

7. Cut open a cocoon in which the insect has pupated and find the
pupa and the cast skin. Compare this pupa, especially in regard to the
distinctness of the legs and other appendages with the pupa of a moth
or butterfly.

8. eens how the fly escapes from the cocoon. Does it gnaw off
acap? Compare it with a bee or a wasp and then with a two-winged
fly. Study its structural characters.

g. Give either orally or in writing a short account of the life of the
Currant Worm. This outline may help: —

The laying of the eggs.

The hatching of the eggs.
The growth of the caterpillar.
The spinning of the cocoon.
The change to the pupa.

The change to the adult fly.

Io. Make these drawings: A leaf with round holes made by young
larve; leaf badly eaten;.a larva, side view; a cocoon; an adult sawfly.
OTHER INSECTS

Read such of the following references as your teacher may direct : —

The Joint Worm, Circular 66, U. S. Bureau of Entomology. Insect Enemies
of Growing Wheat, Farmers’ Bulletin, 132.

CHAPTER XII
Insecticides and their Application

Ir is well known that there are two principal ways in
which plant-feeding insects get their food. Some insects
bite or chew the parts of the plants upon which they feed,
while others are provided with a hollow beak that they
push into the tissues of the plant to suck the sap. All the
leaf-eating caterpillars are examples of the biting insects,
while the plant lice, squash bug, and many related species
are examples of the sucking insects. The picture below
shows the way in which the sucking mouth parts of the
plant louse are inserted among the cells of plant tissues.

This essential difference in the feeding habits of insects
must be considered when we try to kill them by the appli-
cation of insecticides. In the case of a
biting insect, we may hope to poison it
by placing fine particles of arsenic in some
form upon the leaves of the food plant.
As the insect bites the leaves, it will be
likely to eat some of these particles and
be killed. But in the case of a sucking
insect, we must use some insecticide that aos
will kill by coming in contact with the HEAD OF APHIS
. . . “os SHOWING SUCKING
insect itself. Suchinsecticidescommonly foncuz amono
act by reaching the interior of the insect PLANT CxLLs
through the breathing pores, or ¢rachea, isda
and so they are sometimes called tracheal poisons to dis-
tinguish them from the ordinary internal poisons. Kero-

55

156 FARM FRIENDS AND FARM FOES

sene, whale-oil soap, and pyrethrum or insect powder are
among the most important tracheal poisons.

Some plant-feeding larve have such slimy skins that they
are readily killed by dusting with powdered air-slaked lime,
or ashes. The “slugs” on pear, cherry, and rose leaves
are examples of these. ° :

INTERNAL PoIsons

The poisons most commonly used against biting insects
are certain chemical compounds composed in part of ar-
senic. Arsenate of lead, arsenite of lime, and Paris green
are notable examples of such insecticides.

For a long time Paris green was the most important of
the arsenical insecticides. It is a chemical combination of
arsenic and copper, containing, when pure, about fifty-five
per cent of arsenic. It is in a finely powdered condition,
and, when placed in water, the fine particles do not dis-
solve, but remain in suspension. Because of this fact, one
of the most popular ways of applying arsenical poisons to
plants in danger from the attacks of
biting insects, is in a water mixture
by means of a force pump and spray
nozzle.

In its simplest form this process
consists of mixing about a teaspoon-
ful of the poison in a pail of water,
stirring thoroughly to get the powder
evenly distributed through the water.
A small force pump, to which is at-
tached a rubber tube with a spray
nozzle at the end, is then set in the pail. By working the
handle of the pump, the water with the poison particles
in suspension is forced through the tube and nozzle, com-

INSECTICIDES AND THEIR APPLICATION 1 57

ing from the latter in a mistlike spray. This spray is di-
rected upon the leaves of the plant to be protected, covering
each leaf with the liquid.

As soon as the spraying ceases, the water begins to evap-
orate and rapidly disappears, leaving the particles of poison
more or less evenly distributed over the foliage. There
they remain for some time, so that in case a biting insect
feeds upon the poisoned surface it will eat some of these
particles and be killed.

Fortunately the insoluble poison is not absorbed into
the tissues of the plant, so that the process can gener-
ally be carried on without danger to the consumers of
the crop. In the course of a few weeks the particles of
poison are washed away by rain or dew, or blown away
by the wind, or dissipated through the action of the sun-
shine.

A substance that is used to destroy insects is called an
insecticide or insect killer. Thus Paris green is an insecti-
cide. So also is lead arsenate, hellebore, powdered to-
bacco, and insect powder. Each of these substances may
be applied to plants in mixture with water, or most of them
may be dusted on in the form of a dry powder. One may
sometimes use for this purpose simply a porous bag,‘out of
‘which the powder is sifted. It is better, however, to apply
the material by means of one of the many kinds of powder
bellows manufactured for this purpose. With one of the
better forms of these, a pound of Paris green can be evenly
distributed over an acre of potato vines.

Paris green is so powerful a poison that it is often de-
sirable to dilute it with some substance like land plaster,
air-slaked lime, or four. The proportion of poison to dilu-
ent varies greatly with different users. One part of poison
to twenty parts of diluent serves the purpose if the mixing

158 FARM FRIENDS AND FARM FOES

be thoroughly done. When a good powder gun is used, it
is not so necessary to dilute the poison.

During recent years, arsenate of lead has become one of
the most generally used of arsenical insecticides. It is
made by combining arsenate of soda with acetate of lead
in water, and is commonly offered for sale in the form of
a thick paste. This insecticide has a great advantage over
Paris green in that it may be applied even to tender foliage

A SIMPLE SPRAYING OUTFIT

without injury tothe plant. It also remains upon the leaves
longer than any other arsenical insecticides. Under special
conditions it may be advisable to prepare the arsenate of lead
at home, but usually this is scarcely worth while. A dry,
powdery form of this poison has lately been put upon the’
market, and is likely to be very useful for applying with
various sorts of powder bellows.

Trouble has been observed in some Western states in
injury to the health of trees from the use of arsenate of lead.
The poison appears to penetrate the soil and be absorbed
through the roots. On this account arsenic sulphide has
been substituted in an experimental way, and promises to be-
come an important insecticide. It is less soluble than other
forms of arsenic, and also less expensive.

INSECTICIDES AND THEIR APPLICATION 159

EXTERNAL POISONS

The petroleum oils are among the most important of the
contact-killing insecticides. For general use kerosene is
the most convenient of these oils. As kerosene does not
mix with water, dilution with this liquid is not practicable.
It has been found, however, that kerosene may be safely
and effectively used, provided it is first emulsified with hot
soapsuds. This is generally accomplished by adding two
gallons of kerosene to one gallon of a solution made by dis-
solving half a pound of common hard -soap in one gallon
of boiling water, and then churning the mixture by forcing
it back into the same vessel through a force pump. A
creamy emulsion will thus be formed. Before it is ap-
plied, this emulsion is to be diluted with nine or ten parts
of water. It is better to use soft water or rain water for
the dilution.

The undiluted emulsion may be kept for some time, stored
in a dark, cool place. When needed, the required amount
may be measured out and mixed with three or four parts
of boiling water, cold water being added to fill out the di-
lution.

Kerosene emulsion is an excellent remedy for insects
that suck the sap of plants through pointed beaks, such as
the plant lice and the chinch bugs. It kills by contact, but
does not remain upon the plant in an effective condition.
It is applied in a fine spray.

Various forms of crude petroleum have recently come
into use against scale insects. Some proprietary insecti-
cides contain heavy oils so treated as to mix readily with
water, so that they are very easy to spray upon dormant
trees.

The lime-sulphur wash is one of the most efficient con-

160 FARM FRIENDS AND FARM FOES

tact-killing insecticides. It is used chiefly on dormant trees
to kill the San José scale and other scale insects. The
usual formula is: Unslaked lime, 20 pounds; sulphur,
15 pounds; water, 50 gallons. The lime is slaked in 10 or
15 gallons of water; then the sulphur i is added and the prep-
aration boiled for an hour. The rest of the water is then
added and the mixture is ready for use on dormant trees
only.

In place of this mixture boiled by outside heat, lime-sul-
phur washes have lately been made by utilizing the heat of
the slaking lime. ‘These are called self-boiled mixtures and
usually have less sulphur and lime than the formula given
above. They are often used for summer spraying, being
effective against both scale insects and various fungous
diseases.

Strong soapsuds have a decided insecticide value for use
against plant lice and other soft-bodied insects. Whale-oil
soaps are more effective than ordinary soaps, and are gen-
erally used as insecticides.

Pyrethrum powder commonly sold -as insect powder is
a standard insecticide for use against house flies and cer-
tain other insects. It consists of the powdered flower-
heads of the pyrethrum -plants—a genus of composite
flowers which are often grown in gardens for their orna-
mental value. This powder is generally used dried, but
may be applied as a spray — by mixing one ounce of pow-
der with two gallons of water and letting it stand over
night, or by boiling for a few minutes.

Tobacco is another contact-killing insecticide which is
frequently used with good results against plant lice and
vermin on domestic animals. The refuse stems are some-
times utilized in greenhouses as a mulch for growing crops
to prevent the development of. aphides. These stems are

INSECTICIDES AND THEIR APPLICATION 161

also ground into a powder which is applied directly to the
insects. A tobacco decoction is frequently made by boil-
ing the powder or stems
in water or by pouring
boiling water over them.
There is thus formed a -
concentrated solution
which is diluted with cold
water until there are about
two gallons of decoction
for each pound of tobacco
used. The decoction may
be sprayed upon the in-
sects to be killed. Per-
haps the way in which tobacco is most commonly used as
an insecticide is that of slowly burning the stems in green-
houses, producing a smoke which permeates the plants
and kills the pests upon them.

VAPORS AND GASES

There are certain insects which may most easily be
killed: by the use of vapors or gases. For this purpose
bisulphide of carbon and hydrocyanic acid gas are chiefly
employed. The former is a liquid that readily volatilizes
on exposure to the air and kills all insects with which it
comes in contact. It is used to best advantage against in-
sects affecting dry seeds and grains in storehouses, and
against insects affecting the roots of plants.

Hydrocyanic acid gas is a deadly vapor made by pouring
sulphuric acid on cyanide of potassium. It is used to de-
stroy white flies in greenhouses and for various enemies of
citrus fruits in Florida and California. In the case of

162 FARM FRIENDS AND FARM FOES

these fruits, tents are placed over the trees before the gas
is generated.

In California sulphur is used as a remedy for red spiders
and certain leaf hoppers. The sulphur vaporizes in the
hot sunshine, and the fumes are fatal to the insects. In
greenhouses sulphur is also used by painting heating pipes
with it so that the fumes will be given off.

OBSERVATIONS FOR PUPILS

1. Make a list of the injurious plant-feeding insects that you know
which may be killed by internal poisons.

2. Make a similar list of those that may be killed by tracheal poi-
sons. ;

3. What insects in your locality must be killed by the use of noxious
gases?

4. In what ways have you seen insecticides applied?

5- Read such of these references as your teacher may direct : —

Important Insecticides, Farmers’ Bulletin 127. Carbon Bisulphide as an Insec-

ticide, Farmers’ Bulletin 145. Spraying for Orchard Insects, Yearbook Reprint
480.

CHAPTER XIII

The Predaceous Insects

WHite a large proportion of the insects that we meet in
our walks afield are in one way or another injurious to
cultivated crops or domestic animals, there are vast num-
bers of species which may be regarded as either beneficial
or neutral. From the beginning of their lives as eggs
until their death as adults, the injurious insects are beset
by a multitude of enemies. Some of their enemies attack

TIGER BEETLES

them with wide-open jaws, devouring the victims bodily,
while others pierce their bodies with pointed beaks to suck
their lifeblood. Yet others insert lancelike ovipositors by
means of which they leave inside the body of the victim
tiny eggs that develop into parasites whose attacks are as
fatal as those of the larger foes. Those insects that de-
vour the bodies or suck the lifeblood of their victims are
called Predaceous Insects.

There are a great many different groups of predaceous
insects belonging to many families in various orders.

163

164 FARM FRIENDS AND FARM FOES

There is room in these pages for a discussion of only a few
of the more important of these. groups.

PREDACEOUS BEETLES

Among the notable foes of injurious insects the Pre-
daceous Ground Beetles (Carabidz) hold a high rank.
They are active, voracious beetles, having hard, flattened
bodies, strong legs, and large jaws. They hunt commonly
upon the ground or in trees and shrubs for caterpillars and
other insects that may serve as food. Cutworms, army
worms, gypsy moth caterpillars, and similar grass and leaf-
feeding larve are especially likely to be caught by them.

GROUND BEETLES

Many Ground Beetles are black in color, but a few are
greenish blue, and some are marked with golden spots.
Specimens are nearly always to be found beneath boards
or logs lying loosely on the soil surface.

The larvz of most of these ground beetles are also pre-
daceous. They are very active, and are provided with
large jaws for catching and devouring their prey.

The Tiger Beetles (Cicindelide) are perhaps of less
economic importance than the Ground Beetles because they

THE PREDACEOUS INSECTS 165

hunt their prey in a more restricted range. Tiger Beetles
are to be found in open sunny spaces, as along highways
and byways, or on the sandy shores of lakes
and streams. They greedily devour such
insects as they find in their eager wander-
ings. The long legs are fitted for rapid run-
ning ; the large eyes are fitted for seeing over
a wide area; the strong jaws are fitted for
sudden grasping, and the well-developed
wings are fitted for quick flight on the approach of danger.
The wing-covers, legs, and body wall are very hard and
often brilliantly colored in metallic hues.

In early life the Tiger Beetles are curious grublike
larve that live in burrows in hard ground, as along beaten
paths and sandy shores. These burrows are vertical holes,
nearly as large as the diameter of a lead pencil. The larvae
have a strangely flattened head with long, widespread-
ing jaws. Each lies in wait at the top of the burrow,
practically invisible on the smooth surface of the ground.
When an unsuspecting caterpillar or other insect passes
over the waiting head, the jaws grasp the victim, which is
quickly dragged into the burrow to be devoured at leisure.

From an economic point of view the familiar little Lady-
bird Beetles (Coccinellidze) are perhaps
the most important of all the predaceous
beetles. These brightly colored little crea-
tures, in both their larval and adult stages,
feed chiefly upon the destructive aphides

or plant lice, destroying every year billions
LADYBIRD BEETLE of the pests.
AND PUPA

TIGER BEETLE
LARVA

Wherever you find a colony of aphides
sucking the sap from living plants, there you are likely to
find. some of the Ladybirds at'work. They lay their eggs

166 FARM FRIENDS AND FARM FOES

on leaves or stems, the eggs of the larger sorts bearing a

general resemblance to those of the familiar Colorado po-

tato beetle. These eggs soon hatch into the curious Lady-

bird larvze which also feed upon the aphides, destroying
great numbers of them. After some weeks of
feeding, the Ladybird larvz attach themselves to
leaf or bark and change to pupz, soon to change
again to adult beetles.

While most of our common Ladybird beetles
feed chiefly upon aphides, some species devour
bark lice. One of the most noted kinds of

BLISTER beneficial insects is the celebrated Australian

BESTIE Ladybird — Vedalia cardinalis. This insect was
introduced into California to destroy the fluted scale—a
destructive pest in orange groves. The experiment was
quite successful, for the scale insects were materially
checked by their little foes.

PrEDACEOUS Bucs

Probably the most important predaceous insects in the
order of true bugs are the Soldier Bugs (Pentatomidz).
These belong to the genus Podisus ;
they are of moderate size, the larger
common ones being slightly less than
an inch long, with flattened bodies,
well-developed legs, and _ strong,
sharply pointed beaks. There are about a dozen species,
several of which have a horizontal spiny projection on each
side of the back behind the head.

The Spined Soldier Bug is one of the largest and most
widely distributed of these insects. The adults pass the
winter under loose bark, fallen trees, loose leaves, or other
shelter. In spring they come forth and attack such cater-

Soldier-buq

THE PREDACEOUS INSECTS 167

pillars or other soft-bodied insects as they can find, sucking
their lifeblood greedily. They lay the rather large, more
or less barrel-shaped eggs in clusters upon leaves or bark.
The eggs soon hatch into tiny bugs that at first get food
by sucking the sap of various leaves or tender stems.

During the next few weeks these young Soldier Bugs
molt several times, increasing in size each time. The
time when they stop sucking the sap of plants to begin
upon the blood of animals seems not to be known, but
it is probably when they are about half grown. During
the rest of their lives they seem to prefer animal juices to
those of plants, and go eagerly about in search of victims.
Among the most important of these are the larvz of the
Colorado potato beetles, asparagus beetles, cabbage worms,
web-worms, tussock caterpillars, cotton worms, leaf rollers,
codling moth larve, sawfly larve, and even the curious
walking sticks.

This or a closely related Soldier Bug is one of the com-
monest predaceous enemies of the tent caterpillars, occur-
ring frequently in the nest of the American tent caterpillar.

While the Soldier Bugs, as befits their name, are bold
freebooters, constantly invading new areas in search of
victims, the Ambush Bugs (Phymatidz) have quite a dif-
ferent habit. These take up their quarters in flowers or
other shelter where they patiently lie in ambush until some
unsuspecting insect comes within reach of their curiously
made, grasping arms. As soon as it has seized the victim,
the pointed beak serves to suck out the body juices, and
the remains are cast aside.

Five species of Ambush Bugs are recorded for our region.
Only one of these is so abundant and widely distributed as
to be generally known. It may be called Wolff’s Ambush
Bug and is in color a curious mixture of green and yellow.

168 FARM FRIENDS AND FARM FOES

It is especially likely to be found in yellow flowers, waiting
to capture unsuspecting butterfly visitors.

The Wheel Bug is a common predaceous insect in the
Southern states, It is of good size, being more than an
inch long, with a sharp beak and a curious crest on the
thorax that gives it its common name. It feeds largely
upon caterpillars, and belongs to the family of Assassin
Bugs (Reduviidz).

Two-WINGED FLIES

Of the great number of families of two-winged flies com-
paratively few are predaceous. The most distinctive of
these are the Robber Flies (Asilidz), a group of hawklike
creatures, some of which may often be seen in open fields.
Nearly a thousand distinct species
are found in North America. The
more familiar forms have powerful
wings and long legs and abdomen.
They commonly rest on low shrubs
or plants whence they can readily
pounce upon any flying insect that
passes near. Honeybees are so
often killed by them that in some

RouEER FEN regions these flies are called bee

_ killers. Such victims are caught by

the powerful legs, and quickly sucked dry by the voracious

robbers. A few species bear a striking resemblance to

bumblebees and wasps, from which they are at once distin-
guished by having but one pair of wings.

So far as their earlier stages have been described, the
larvee of these flies seem to be largely predaceous also.
They live in damp soil and rotting wood, apparently feeding
upon the other insects found in such situations.

THE PREDACEOUS INSECTS 169

A colony of aphides or plant lice offers many oppor-
tunities to study the relations of various groups of insects to
one another. In such a colony there are forms of winged
and wingless aphides as well as several kinds of enemies
that attack them. Among the latter are the tiny four-
winged parasites, the young and adult ladybird beetles, and
the strange Aphis Lions. In addition to these, you can
generally find, also, a curious footless grub blunt at one end
and sharply pointed at the other, which impales the plant
lice one at a time on its pointed end, sucks the lifeblood, and
casts aside the empty skins. These are the larve of the
Syrphus Flies (Syrphidz), many species of which in the
Jarval state thus prey upon the aphides.

The Syrphus Flies are generally a little larger than the
common house fly and may be found in abundance visiting
flowers.in search of pollen and nectar. The
mother flies lay their elongated whitish eggs
on leaves and bark amid colonies of plant lice.

The eggs shortly hatch into the curious larvee enim
that prey upon the aphides. When full grown, FLY
the syrphid larve change to pupz, still upon

the leaf or bark, and change again a little later into adult
flies.

Four-WINGED FLIES

The great order of Four-winged Flies — Hymenoptera —
contains several families that may be classed to a greater
or less extent in the predaceous group. One of the most
important of these is that of the Ants, which are so univer- ©
sally distributed over the surface of the earth. Most of these
ubiquitous little creatures have a wide range of food, taking
almost anything, living or dead. There is no doubt, how-
ever, that they are important foes of noxious insects, de-

170 FARM FRIENDS AND FARM FOES

stroying unsuspected numbers of eggs, larve, and later
stages of plant-feeding insects.

The Social Wasps (Vespidz) are well-known predaceous
insects. The adults build paper nests in which the young
are reared, being fed largely with various insects that the
worker wasps catch for them. These workers also feed
freely upon such insects, though
they also eat the nectar of
flowers and other kinds of food.

The various groups of Soli-
tary Wasps mustalso be classed
with the predaceous insects,
though their peculiar habits
ally them in a way with the true
parasites. The Mud Wasps
and the Digger Wasps provision their cells and burrows with
flies, grasshoppers, caterpillars, spiders, and other crea-
tures. These victims are paralyzed by the sting of the wasp
so that they lie helpless in the cell in which the wasp egg
is laid. This egg soon hatches into a larva that feeds upon
the paralyzed prey, finally transforming to a pupa and later
to an adult wasp.

WHITE-FACED HORNET

OTHER ORDERS

Comparatively few important predaceous families are
found in the other orders of insects. Some of these, how-
ever, are friendly insects of great value, serving a notable
purpose in the economy of nature.

What the swallows are among the birds, the Dragon Flies
are among the insects. These powerful creatures are won-
derfully adapted to their life work. With enormous eyes
that see in practically all directions, with powerful wings
that carry them with lightning rapidity through the air, with

THE PREDACEOUS INSECTS

171

a long abdomen that serves admirably as an aérial rudder,
and with strong front legs and great jaws fitted for grasp-

ing and biting their victims, they may in-
deed appear as formidable dragons to less
fortunate insects. In their earlier stages
these insects develop in the water, where
they are also predaceous.

The Dragon Flies are commonly di-
vided into two groups: those in which the
wings are held vertically when the insect
is at rest are called Damsel Flies; those
in which the wings are held horizontally
when the insect is at rest are called
Dragon Flies.

i DRAGON-FLY

Among the many parasitic and predaceous insects to be |
found amid colonies of plant lice, the Aphis Lions are per-

EGG Mass OF
MANTIS

haps the most remarkable. These are
long-legged, slender-bodied creatures
with strange long jaws between which
they grasp their prey while they suck
the body dry.. They are the larve of the
Golden-eyed Lace-winged Flies (Chryso- -
pidz).

The curious Mantids of the order Or-
thoptera are also remarkable predaceous.
insects. They are closely related to the
walking sticks and lie in wait till vari-
ous insects come within reach of their
grasping front legs. The native Praying
Mantis is not uncommon in the South-
ern states, while another species from

Europe has lately been introduced into New York state.
There are, of course, many predaceous creatures among.

172 FARM FRIENDS AND FARM FOES

the spiders, mites, and myriapods, related to the insects
proper. But the limitations of space forbid their discus-
sion here.

OBSERVATIONS FOR PUPILS
PREDACEOUS BEETLES

1. If you can find any of the Predaceous Ground Beetles, keep them
alive in a vivarium for a few days. Furnish cutworms, cabbage worms,
or other caterpillars for food.

2. See if you can find any Tiger Beetles along paths and roadsides.
Which way do the beetles face when they alight — toward you or not ?
Catch two in an insect net. Keep them in a vivarium and furnish
caterpillars for food.

3. See if you can find any burrows of Tiger Beetle larve in smooth-
trodden ground. :

4. Bring in a few Ladybird Beetles and keep ina vivarium. Furnish
aphides for food. See if you can find any Ladybird larve, pupe, or
eggs.

5. For a fuller account of Tiger Beetles read Life Hustorzes of
American Insects, pages 19-27; of the Ladybird Beetles, Stories of
Insect Life, Second Series, pages 49-55.

PREDACEOUS BUGS

1. Look in tent caterpillars’ nests in spring to see if you can find any
Soldier Bugs. Or later in the season see if there are any on the potato
vines. If you find any, keep them in vivaria for a few days and see the
way they take their food.

z, In summer or early autumn sweep clusters of herbage for the
‘yellowish Ambush Bugs. Study their structure to see the sharp beak
and the curious front legs fitted for grasping.

3- If you live where the Wheel Bugs are found, keep-one alive and
watch it feed upon caterpillars.

4. Read the life story of the Wheel Bug in Zhe Jusect Book, pages
294-296.

TWO-WINGED FLIES

1. On warm days look for the Robber Flies along sunny roads.

Listen to the quick buzz as they fly up and watch how they lie in wait
for prey.

THE PREDACEOUS INSECTS 173

2. Examine a colony of plant lice carefully. Try to find the white
eggs, the footless larva, or the curious brown puparia of some of the
Syrphus Flies. Watch one of the larve through a lens to see the way
it impales its victims.

3- Read the account of the Robber Flies in Zhe Jnsect Book, pages
141-143; of the Syrphus Fly in Stories of Insect Life, First Series,
pages 50-51.

ANTS AND WASPS

1. Watch the surface of an ant’s nest to see if any insects ave carried
to it. .

2. Watch wasps and hornets as they fly about porches and near
houses to see if they catch flies and other insects.

3- Open the cells of a Mud Wasp’s nest to see the paralyzed spiders
or caterpillars inside.

4. Watch the places where Digger Wasps make their burrows to
see the insects at work.

5. Read such of the following accounts of the life histories of wasps
as you have access to: —

The Insect Book, pages 18-30. American Insects, pages 490-510. Nature Biog-
raphies, pages 102-106. Life Histories of American Insects, 147-178. Stories of
Insect Life, Second Series, pages 24-29, or the book by Professor and Mrs. Peck-
ham, entitled Ze Solitary Wasps.

OTHER PREDACEOUS INSECTS

1. Watch the Dragon Flies and Damsel Flies in summer. Notice
the position of the wings when the insects alight.

2. Read the account of Dragon Flies in American Insects, pages 75—
89; also the accounts of the Praying Mantis in Ze Jnsect Book, pages
326-328 ; Storzes of Insect Life, Second Series, pages 63-68.

CHAPTER XIV
The Four-winged Parasites

Ir is fortunate for mankind that almost all species of in-
jurious insects have insect enemies that destroy them.
These insect enemies are divided into two groups as regards
the methods by which they kill their victims. There is no
hard and fast line to be drawn between these groups, but
in general we may safely say that the insects which destroy
other insects are either parasites or predaceous insects. As
a rule, the parasites develop in the larval state within the
bodies of their victims, and, as a rule, the predaceous insects
feed, sometimes during the earlier stages, sometimes during
their adult stage, and sometimes during both, upon their vic-
tims, attacking them from the out-
side either by thrusting a pointed
beak through the skin and sucking
their lifeblood, or else by devouring
them bodily.

Tue IcHNEUMON FLIES

One of the most important groups
of parasitic insects is that of the
Ichneumon Flies. These are slen-
der-bodied, more or less wasplike
creatures, with four wings, long
antenne, and well-developed legs
adapted for running. You may very often see-them run-
ning rapidly over the surface of leaf or bark, in search
174

ICHNEUMON FLY OVIPOS-
ITING IN COcOOoN

THE FOUR-WINGED PARASITES 175

of victims in which to lay their eggs, constantly vibrating

their antennae. Oc-
casionally, also, you
may see them visit-
ing such flowers as
have the nectar
freely exposed to lap-

ping by their short €==

tongues. Or you
may see them in the
evening as they fly
about a light to
which they are at-
tracted..

The Ichneumon
Flies vary greatly
in size, form, and
habits. Some are so
minuteas tobe barely
visible to the un-
aided eye, while
others measure sev-
eral inches in length,
with long antennz
and slender oviposi-
tors extending be-
hind the abdomen.

Among the largest
of the Ichneumon
Flies are the inter-
esting brown insects
called the: Ophion
Flies. The life his-

LLONG-TAILED ICHNEUMON FLY

176 FARM FRIENDS AND FARM FOES

tory of one of these in brief is this: The adult fly de-
posits its egg within the body of a caterpillar, especially the
caterpillars of the large silkworm moths, like the polyphe-
mus moth or the cecropia moth. This egg shortly hatches
into a small white footless maggot that absorbs the body
juicés of the host, as the victim is often called, but at first
does not seriously interfere with its development. The
caterpillar with its enemy inside continues to feed and grow
for some time. It is commonly able to spin its cocoon and
perhaps change to a pupa within the cocoon before the
larva of the parasite becomes so large as to kill the host.
It does kill it, however, finally, and then within the protect-
ing shelter of the host’s cocoon,
the larva of the Ophion Fly
changes to achrysalis. The fol-
lowing spring it will change again
to an adult fly, like the one that
laid the egg in the caterpillar so
many months before. This fly
is provided with sharp jaws by
means of which it gnaws its way
out of the cocoon and flies freely
about. It has thus completed
the cycle of a parasite’s life.
Sometimes the egg of the par-
_ asite is not laid within the cater-
d . pillar until after it has spun its
se alsa amee biareeahls cocoon. This is often the case
seiogtae “"* with certain medium-sized Ich-
neumon Flies of the genus
Pimpla. These may sometimes be seen standing upon the
cocoons of the common apple-tree tent caterpillar, with the
ovipositor thrust down through the cocoon in the. manner

THE FOUR-WINGED PARASITES 177

illustrated on page 174. The egg develops within the
body of the host into a white footless maggot that soon
matures as a larva and changes to a pupa, which in turn
shortly changes into an adult Pimpla.

Many of the Ichneumon Flies deposit their eggs within
the burrows of larvz that bore in the stems of herbaceous
plants or the bark or trunks of shrubs and trees. . In such
cases, it evidently would be difficult for the mother parasite
to find precisely the location of the burrowing larva, so she
simply deposits her egg within the burrow of the latter,
and the little larva that hatches from this egg is 2 penerally
provided with some method
by which it is able to reach
its victim. Instead, however,
of developing on the inside
of its host, it usually simply
attaches itself to the skin and
sucks its lifeblood from the outside. It finally kills the
host, becomes full-grown as an Ichneumon larva, and changes
first to a pupa, and a little later into an adult fly that is able
to eat its way out through the bark of the plant.

ICHNEUMON FLIES

MICROGASTER FLIES

One of the most abundant groups of the Ichneumon
Flies is that of the Microgaster Flies. These are rather
¢ small insects that deposit their

eggs in smooth-skinned. caterpil-
SE, . lars of many kinds. As a tule,
Cocoons oF Microcaster each female fly is provided with
ELS a pointed -ovipositor with which

she can pierce the skin of the caterpillar to insert her eggs
within its body. These eggs shortly hatch into tiny mag-
gots that develop at the expense of the tissues of the un-

178 FARM FRIENDS AND FARM FOES

fortunate host. Ina few weeks the maggots become full-
grown, and then each burrows its way out through the skin
of the victim. Once outside,
each maggot spins some sort of
silken cocoon within which it
changes first to a pupa, and
later to an adult Microgaster
similar to the one that laid the
eggs.

There is much variation in
the color, form, and arrange-
ment of the cocoons of these
Microgaster Flies. Some are
white, others yellow. Someare
formed singly, others side by
side in a compact mass, and still

CATERPILLAR wiTH Cocoon others in a loose mass of fluffy
Mass OF MICROGASTER PARA- =
silk.
SITES

There is also great variation
in the number of parasites to a single caterpillar. Some-
times there is but one parasite to a host, as in the case of
certain leaf miners, sometimes there are only a few, but
more commonly there are a great many — several hundred
in the case of the tomato worm and other sphinx cater-
pillars.

PLANT-LOUSE PARASITES

Almost any colony of plant lice will furnish examples of
the extremely interesting family of tiny flies that prey
especially upon the aphides. These are little four-winged
flies so small as to be barely visible to the unaided eye,
which develop in their younger stages in the bodies of the
plant lice, and cause the death of untold billions of these
vexatious pests.

THE FOUR-WINGED PARASITES 179

A considerable proportion of these tiny parasites belong
tothe genus Aphidius. The fly generally deposits her egg
within the abdo-
men of the aphid.
The egg shortly
hatches into a
tiny footless
maggot that lives
within the body
of its host, ab-
sorbing the ma- : ff
terials of growth Y cps zt
from it, and often
being visible
while the host in-
sect apparently
is stillalive. Fi-
nally the parasite larva becomes fully developed, absorb-
ing practically all the contents of the aphid’s body, kill-
ing it, and leaving only the inflated skin of the latter to serve
as a protection to the parasite. Within this brown inflated
skin, the larval parasite changes to a pupa and very soon
afterward changes again to a tiny fly, resembling the one
that laid the egg. This fly gnaws out a circular piece in
the skin of the dead host, making a hole through which
it emerges to continue the good work of aphis destruction.

Very often these little parasites are important means of
checking outbreaks of destructive aphides. The parasite
of the grain aphis, illustrated.herewith, is a notable example
of this. Under certain conditions which are favorable to
the development of the plant louse, but not favorable to the
development of the parasite, the former become exceedingly
destructive in the grain fields of the South and West.

Aphis with parasite
larva ‘inside

PARASITE
of

GRAIN . APHIS

MAGNIFIED

Aphis Killed by
parasite:

180 FARM FRIENDS AND FARM FOES

Under ordinary conditions, however, this pest seems to be
held in check to a great extent by the tiny fly that develops
in enormous numbers at its expense.

PRIMARY AND SECONDARY PARASITES

The ichneumon flies discussed in the previous pages de-
velop as parasites of various plant-feeding eateepiets
They are known as primary parasites.

It very commonly happens, however, that these primary
parasite larvee are themselves attacked by other ichneumon
fly larvee that attach themselves to the former and suck
their lifeblood. Such parasites of parasites are said to be
secondary pavasites.

It also happens sometimes that one of these secondary
parasites is in turn attacked bya third larva that sucks out
its lifeblood. Such parasites of parasites of parasites are
said to be ¢ertiary parasites.

Perhaps you will be able to remember these facts better
if I quote a famous old rhyme : —

The little fleas that do us tease,
Have other fleas that bite ’em,
And these in turn have other fleas

And so ad infinitum.

In general these parasites of parasites are spoken of as
hyperparasites.

Attention has recently been called by W. F. Fiske to an-
other important phase of parasitism. It very commonly
happens that two or even more primary parasites attack
the same caterpillar. One of these may devour the avail-
able food so rapidly that the other will die. Or they may
both become fully developed, but be so dwarfed from the
limited food supply that they are unable to lay eggs for an-

THE FOUR-WINGED PARASITES 181

other brood of parasites. Or they both may die from lack
of food.

Mr. Fiske has applied the term superparasitism to this
excessive parasitism of primary hosts. He classifies the
various conditions that may exist as follows: —

I. One parasite lives ; the other dies.

(a) The survivor preys upon the other as an acci-
dental secondary parasite. Of common occur-
rence.

(2) The survivor destroys the other by bringing
about the premature death of the host and may
or may not devour it incidentally. Of common
occurrence.

II. Both parasites live.

(c) Neither is the worse for the circumstances.
Very rare.

(2) One or both are so seriously weakened and
stunted as to bring about a material reduction
in their capacity for reproduction. Common..

III. Neither parasite survives.

(e) This may be brought about through the prema-
ture death of the host through excessive para-
sitism (commonly); or

(f/) Through the inability of either parasite to
complete its transformations. on the limited
supply of food. Common.

If you will stop to think what must be constantly hap-
_ pening in the world of insects on account of the existence
of these many primary, secondary, and other parasites, you
will see that the relations between them must be very com-
plicated. A caterpillar that is a great crop pest becomes
abundant. Its primary parasites soon become abundant

182 FARM FRIENDS AND FARM FOES

also, because they can multiply rapidly when their caterpil-
lar hosts are numerous. And so they tend to check the
caterpillar outbreak. But when the primary parasite is
abundant, the secondary parasite can also multiply rapidly.
So these will tend to check the numbers of the primary
parasite and thus relieve, so to speak, the pressure upon the’
caterpillars. The case will also be complicated by the
many examples of superparasitism. Consequently there is
a constant fluctuation in the numbers of these different in-
sects —each one now abundant, then scarce — with a ten-
dency toward a normal level. This complicated condition
is often spoken of as the Balance of Nature.

THE CHALCID FLIES

The ichneumon flies are not the only important group of
four-winged parasites. From an economic point of view
the great family of Chalcid Flies is perhaps of as great
value, although on account of their smaller size they are
not so well known. It is believed, however, by Dr. L. O.
Howard, our foremost authority upon these insects, that
there are more species in this family than in any other of
the great order of four-winged flies.

The Chalcids are very small four-winged flies that develop
in the earlier stages of other insects. They are especially
likely to infest the eggs and larvee of butterflies, moths,
beetles, and sawflies, as well as the larve of great numbers
of two and four-winged gallflies, ichneumon flies, wasps, bees,
and two-winged flies. They are also very destructive to
scale insects and sometimes develop in plant lice and other
families of true bugs, as well as in the eggs of tree crickets
and other members of the order Orthoptera.

In the case of many Chalcid Flies the life history seems
to be as simple as in that of the more familiar ichneumons.

THE FOUR-WINGED PARASITES 183

The mother insect deposits one or more eggs in a caterpil-
lar. The eggs hatch into tiny maggots. The maggots
grow inside the body of the host, absorbing its substance.
They finally change to pupze, generally within the body of
the dead or dying host, to emerge later as fully developed
Chalcid Flies.

Many of the Chalcids are parasites of borers, gallflies,
and leaf miners. Asarule, the larve in such cases develop
as external parasites upon their victims. You may often
find examples of these if you will examine a number of
leaf-miner cavities. Many other Chalcids are parasites
upon the larvee of the ichneumon flies—that is, they are
secondary parasites. In such cases, also, the Chalcid larvze
generally develop as e ‘ternal feeders upon the ichneumon-
fly larvee.

A considerable number of the Chalcid Flies, however,
have lives that cannot be told in the few words that will
give the life history of the others. They go through so
wonderful a course of development that it has required the
most careful studies of many scientists for years to trace it
out. Even now we know but little, and that only in re-
lation to a very few species. But what we do know enables
us to explain certain facts which before were very puzzling.

If you will bring in a lot of nearly full-grown larve of
the Cabbage Plusia and keep them in a vivarium, a good
many of them will be likely to die because they are in-
fested with parasites. If you will isolate those that die,
keeping them in small bottles or boxes so you can see how
many parasites come from each caterpillar, you will prob-
ably find that from some there emerge hundreds if not
thousands of tiny four-winged Chalcid Flies. In one case
three thousand such flies were counted from one cater-
pillar.

184 FARM FRIENDS AND FARM FOES

If you stop to think, you can scarcely fail to wonder
how it was possible for one or even several mother flies
to lay so many eggs in a single caterpillar. Indeed, it has
been found that one fly probably cannot Jay more than one
or two hundred eggs, and it would seem hard to believe
that a dozen or more of
these flies laid their eggs
upon the Plusia caterpil-
lar all at once. But if
they did not do this, how
may we account for the
three thousand parasites?

CHALCID PARASITE OF GYPSY MOTH The observations of sev-
Ecos eral European entomolo-
Magnified

gists indicate that the life
story of these parasites is something like this : —

The Plusia Moth lays its egg upon the cabbage leaf.
‘Shortly afterward the Chalcid Fly lays its egg within the
egg of the Plusia Moth.

The Chalcid egg remains within the Plusia egg, so that
the latter hatches into a caterpillar with the unhatched
Chalcid egg within its body.

After a time the Chalcid egg hatches, but not into a
single larva. By a wonderful process its contents develop
into hundreds of tiny larvz that live on the body substance
of the Plusia caterpillar. They grow gradually inside
their caterpillar host. The latter finally dies, and the thou-
sands of parasites change to pupz within the skin. A
little later they change to flies.

So, instead of the original egg developing into one Chal-
cid Fly as is so often the case, it develops into hundreds
‘if not thousands. Suppose a female Chalcid Fly laid an
egg in each of a hundred Plusia caterpillars, and each egg

THE FOUR-WINGED PARASITES 185

developed into a thousand flies. Of how many flies would
she be the mother?

Do you wonder that these parasites are important ene-
mies of injurious insects, and are often able to check seri-
ous outbreaks of great crop pests?

THE PROCTOTRYPID FLIES

The third great group of insect parasites is that of the
Proctotrypid Flies. These are nearly all very minute crea-
tures somewhat similar to the chalcid flies. A large pro-
portion of them develop in the eggs of other insects, sev-
eral sometimes emerging from a single host egg. Many
of them are parasites upon parasites, andsome undergo a
development of many larve from one egg, as in the case
of some of the chalcids.

There is one giant in this family. It is the strange
Pelecinus Fly pictured below. Apparently it is a parasite
of the white grub— the larva of the common May beetle.
The female Pelecinus is much smaller than the male and
is a very different-looking insect.

PELECINUS. FLY

186 FARM FRIENDS AND FARM FOES

OBSERVATIONS FOR PUPILS

AMERICAN TENT CATERPILLAR

1. Collect a few nearly full-grown caterpillars from the nests late in
spring and keep in vivaria, feeding as necessary. See how many of
them are killed by parasites. ;

2. Collect from the nests any cocoons that may be made in them.
These are pretty sure to be infested by parasites. See how many sorts
of flies come from them.

3. See if you can find in the nests peculiar shrunken caterpillar skins
with a cocoon inside. Keep these and rear the parasites.

4. Look up these references : —

Stories of Insect Life, First Series, pages 10-11. Nature Biographies, pages 22-34.

CABBAGE BUTTERFLY

1.- Early in spring look on boards, fences, or the sides of build-
ings near gardens where cabbages have been planted, for masses of the
small yellow cocoons of microgaster parasites. Keep such cocoons in
closed vials or boxes to rear the flies. If two kinds of flies emerge, the
larger black ones will be the microgaster flies, which are the primary
parasites, and the smaller flies will be secondary parasites.

2. Early in spring collect a number of the cabbage butterfly chrysalids
that may be found in boards and fences near old cabbage patches.
Keep in small_vivaria. From some of them you will be likely to rear
hundreds if not thousands of small chalcid flies. Count the number
from one chrysalis. Let the flies escape to continue their good work.

3. In autumn collect a number of cabbage worms. They may gen-
erally be found abundantly on cabbages. Keep them in vivaria. See
how many are killed by parasites.

4. Read The Insect Book, pages 57-60; Stories of Insect Life, First
Series, pages 16-17.

FALL WEB-WORM

1. Early in autumn collect a score or more nearly full-grown fall
web-worms and place in vivaria. Several of them are likely to be killed
by parasites.

2. Find cocoons of the fall web-worm in which external parasites are
preying on the larve.

3- Read The Jusect Book, pages 64-68.

THE FOUR-WINGED PARASITES 187

APHIDES OR PLANT LICE

1. Find some colonies of aphides on some shrub, tree, or herb.
They are commonly abundant on cabbage leaves. Look carefully for
brown inflated specimens. These are parasitized. -

2. Place some of these parasitized aphides in small vials and rear
the adult parasitic fly. Notice the hole through which it comes.

3. Read Life Hestories of American Insetts, pages 197-199.

SPHINX CATERPILLARS

1. Look over tomato vines, grapevines, Virginia creeper, and other
plants to see if you can find any large sphinx caterpillars bearing on
their backs the cocoons of microgaster flies. If you find any, place each
inavivarium. ,

2. Notice whether the parasitized caterpillar eats and how long it
lives. When the flies emerge, notice whether they are all the black
microgasters which are the primary parasites or whether there are some
bright-colored chalcid flies, which are secondary parasites.

3. Read these references : —

Life Histories of American Insects, pages 181-188. Nature Biographies, pages
122-131.

CHAPTER XV

The Two-winged Parasites

In the great order of two-winged flies (Diptera) there
are many parasites of other insects. A large proportion of
these belong to the family of Tachina Flies (Tachini-
dz). These are mostly insects of moderate size, similar
in appearance to the common house fly but usually some-
what larger.

These Tachina parasites have long been recognized as
among the most important enemies of such smooth-skinned
caterpillars as cutworms
and army worms, often
ak = destroying millions of

these pests at the time

of a single outbreak.
TACHINID of ARMY- WORM The life history as shown

. by the species that in-

fests the army worm is briefly this: The adult flies de-
posit their oval whitish eggs upon the outside of the skin
of the caterpillar. These eggs shortly hatch into tiny
larve by burrowing through the eggshell and also through
the skin of the caterpillar, finding lodgment among the
body tissues. Here they rapidly develop into whitish foot-
less maggots that finally kill the host and emerge to change
to the pupa state at or near the surface of the soil. They

soon again change to adult flies to continue the generation
of the parasite.

188

THE TWO-WINGED PARASITES 189

VARIATIONS IN LIFE HISTORIES

Until recently the life histories of the other Tachina
Flies have been supposed to be similar to the development
of that preying upon the army worm. But the careful
studies of Dr. C. H. T. Townsend upon the parasites of the
gypsy and the brown-tail moths show a marvelous variation
in the life histories of these flies, and establish their great
value as enemies of hairy caterpillars as well as of those
with smooth skins. Dr. Townsend found that at least one
of the flies that preys upon the brown-tail moth deposits
eggs upon the young caterpillars, the eggs hatching and
penetrating the skins of the caterpillars, much as in the
case of the parasite that kills the army worm. But the
other Tachinid parasites had surprisingly different life his-
tories, the discovery of which required months of patient
observation.

Several species of these flies deposit their small eggs upon
the leaves where the caterpillars are feeding, the eggs be-
ing often fastened to the freshly eaten edge of the leaf.
The eggs are swallowed by the caterpillar with the leaf
particles, generally escaping injury from the jaws because
they are so minute. Soon after being swallowed, the eggs
hatch into tiny maggots that burrow through the wall of
the alimentary canal into the general body cavity of the
host. Here they absorb food and grow, finally changing
to pupz and again to adult Tachina Flies — meanwhile
causing the death of the caterpillar.

These observations upon the leaf laying of the Tachinid
eggs indicated an unsuspected ability on the part of the
flies to overcome difficulties. Evidently the hairy clothing
of the caterpillars would prove of no value as a protection
from parasites if the very food is laden with the eggs of

190 FARM FRIENDS AND FARM FOES

the enemy. But the next species to be studied revealed a
still different method of reaching the interior of the host.
Observations upon the development of the Tachinid eggs
indicated the probability that some kinds of these flies would
deposit living larve instead of eggs. Two species were
especially studied, and it was found that the flies were fur-
nished with “a long curved sheath, into the base of which
the ovipositor fits, and which tapers to a microscopically
sharp point.” By means of this
instrument the flies are able to
thrust the sheath between the hairs
of the caterpillar, cut a hole in the
skin, and insert the living larva in-
side the body of the victim. From
« the point of view of the parasite
this method has obvious advan-
tages: the young larva is placed
amid favorable surroundings at once
with no danger that it will find itself

TACHINA PARASITE OF
Gypsy MOTH
Magnified attached to a molted caterpillar skin.

And the interesting fact was brought out that various na-
tive flies have a similar sheath and doubtless a similar life

history.

A REMARKABLE LiFe History

It is not strange that Dr. Townsend found a species that
we may for convenience call the Large-horned Tachina Fly,
the ‘most remarkable as regards startling deviations from
the previously known manner of reproduction” in the
group. It was at first supposed that these flies would
deposit their eggs upon the skins of caterpillars in the
old-fashioned way. Toa female fly having this habit, the
presence of a good-sized gypsy or brown-tail caterpillar

THE TWO-WINGED PARASITES I9t

should be welcomed as an opportunity for depositing an
egg and thus fulfilling the chief purpose of her existence.
Consequently the investigators were puzzled to find that
these flies not only did not so deposit their eggs, but were
actually alarmed by the presence of the caterpillars.

It was easily learned through the study of dead flies that
the eggs were large elongated objects, too large to be swal-
lowed safely by the intended victims, — safely, that is, for
the parasite. Hence it could not be that they were laid
upon the leaves to be eaten. If they were not to be de-
posited on or in the caterpillars and were not to reach the
interior cf their hosts by being eaten, how was it to be
done?

The final solution,may well be given in Dr. Townsend’s
own words: “ After much patient observation and experi-
ment this question was answered. The flies were found to
deposit living maggots, not on or in the caterpillars, but,
most remarkable to relate, on the green shoots, leaf stems,
leaf ribs, and even sometimes on the surface of the leaves.”
This was not a matter of chance, however, for the flies
hovered in the air above the leaves where the caterpillars
were at work, evidently seeking for favorable places for
depositing the larve. By some sense — perhaps sight, per-
haps smell, possibly both —they knew when the caterpil-
lars were present and could not be induced to deposit on
branches where they were not present or had not been
crawling. 2

In crawling along, many of these caterpillars of the great
group of silk spinners have an interesting habit of marking
their trail by a silken thread which is continually spun from
the silk glands in the mouth as the larva marches to its
feeding grounds. This thread serves to guide it back to
its permanent or temporary quarters when its meal is fin-

192 FARM FRIENDS AND FARM FOES

ished. If you will look at a nest of our native tent cater-
pillars in spring, you will see silken webs leading from the
tents in all directions. These are made by the individual
caterpillars on their daily journeys in and out.

It is evident that the Tachina Fly knows about this trail
of the silk-spinning caterpillar. And apparently she can
tell whether it is a fresh trail on which the caterpillar has
gone out and not returned, or an old one which would be
comparatively useless for her purpose. ‘ Doubtless,” writes
Dr. Townsend, “the flies larviposit only on freshly laid
strands which have not lost the odor of the caterpillar.”
Upon this fresh strand of silk she deposits a living larva
that is wonderfully adapted to making its way in the world.
On the hind end of its body there is a curious sucker-like,
membranous, cup-shaped case, by means of which the tiny
maggot is fastened to the leaf on or near the silken thread.
On the front end of its body is a slightly sickle-shaped hook,
admirably designed for rending the skin of the caterpillar.
Thus it is anchored in the path of its prospective victim
with its stiletto ready for business at a moment’s notice.
As long as all is quiet, it lies lazily down, but on any dis-
turbance, such as would be made by the homeward return
of the caterpillar, our young pirate becomes active and
ready to fasten upon the expected caterpillar.

If you will examine a good-sized web-worm or gypsy
moth caterpillar you will find that it is well protected by its
hairy covering along its back and sides. But on the lower
surface, the skin is more exposed, and it is obvious that this
Tachinid larva lying in wait with its stiletto will find the
caterpillar as it crawls above it an easy victim for its hook.
When the mouth hook is thrust through the skin, the pull
of the caterpillar loosens the hold of the parasite upon the
membranous case at the hind end of its body and the par-

THE TWO-WINGED PARASITES 193

asite remains with its host, working its way through the
skin to the inside and there remaining until it reaches its
full development into the adult fly, at the expense of the
life of its caterpillar victim.

OBSERVATIONS FOR PUPILS

1. Examine carefully the caterpillars you find to see if any of them
show Tachinid eggs.

2. Watch for the development of Tachina Flies from the caterpillars
you rear in breeding cages. :

Read : —

The Value of Insect Parasitism to the American Farmer, Yearbook Reprint
447. The Relations between Birds and Insects, Yearbook Reprint 486.

CHAPTER XVI
The Pollination and Fertilization of Flowers

One of the most striking features of the early spring
landscape in a fruit-growing region is that of the great
white masses of cherry blossoms. These are to be seen at
long distances wherever a cultivated cherry tree is growing.
If you will pick one of these blossoms and look at it care-
fully for a moment, you will be
able to see readily the various
parts of which each flower con-
sists. ;

Hold the stem in one hand and
you will see a little green cup at
its upper end; this cup is called
the receptacle. Around the outer
edges of the cup are five small
lobes; these are called the sepals.
They are greenish and served to
protect the flower when it was a

CHERRY BLOSSOMS bud. In front of the sepals and
between them are the five large

white petals, which make the flower conspicuous. Inside
the petals are many small pollen-bearing organs called
Stamens ; each stamen consists of a sort of stalk or filament
and a pollen bag or anther. Very likely the anther in
the specimen in hand will have broken open so that the
powdery ollen is plainly visible. In the center of the
flower is a single slender vertical object called the pzszz/.

194

THE FERTILIZATION OF FLOWERS 195

It will be worth while to cut away carefully the stamens,
petals, sepals, and a portion of the receptacle on one side
in order to get a complete view of the
pistil. You will then readily see, es- Stame nae) y ~Pistit
pecially through a hand lens, that this \ WA >
pistil consists of an enlarged part at the
bottom called the ovary, above which
is a slender stalk called the sty/e, on
the upper end of which is an enlarged
portion called the stzgma. If now you
cut away carefully a piece of one side
of the ovary, you will see within a single little egg-shaped
object called the ovale.

If you look carefully with a lens at.the glistening surface
of the receptacle, you will probably see certain drops of
liquid; these are drops of xectar which the bees gather
when they visit the blossoms and carry home to make into
honey.

A week or so after the cherry trees have begun to blos-
som, the landscape is lighted up by the beautiful flowers
of the apple trees. These may be seen at great dis-
tances, and by their color and odor serve to attract the
notice of thousands of insects, which may be seen and
aii heard flying among the blossoms,
7 busily gathering both nectar and
pollen.

If you examine an apple blossom
carefully, you will see that in many
S\ respects it resembles the -flower of
7 the cherry, but differs in having five
styles and stigmas which at their base are united to form
a compound ovary. In this ovary are five little cells in
which the ovules are held. There is thus one of these

Pollination ;
‘|i

a
Fertilization( =|:

Vya

196 FARM FRIENDS AND FARM FOES

cells for each style and stigma. You-.should see the in-
teresting nectar cup on the top of the ovary, on which
glistening drops of nectar may generally be found.

SouasH BLossoms

People are sometimes puzzled over the fact that cucum-
bers and squashes seem to have so many blossoms in pro-
portion to the number of fruits produced.
If you examine, - however, the flowers
upon one of these plants, you will soon
be able to tell the reason for this. You
will find that most of the flowers consist
CucuMBER: POLLEN- only of sepals, petals, and stamens, and-

BEARING FLOWER that such flowers are easily recognized
from a side view, by the fact that there
is below the blossom no little cucumber
or squash to develop later into a fruit.
These flowers are stamen-bearing or stam-
nate blossoms, and in general they are
smaller than the other kind of flowers
found upon the same plants, which con-
: sist of sepals, petals, and a single pistil.
CocuMBER: SeED- The ovary of the pistil which you will
BEARING FLOWER 5 te

recognize at once as a miniature cu-
cumber or squash is below the main blossom, but has a
style that runs up through the center of the flower and
bears upon its tip a well-developed stigma. These are the
seed-bearing or pistzllate flowers.

If you should cut open the ovary of one of these pistillate
flowers, you would find inside a large number of tiny seed-
like bodies called the ovules. In order that these ovules
may develop into seeds, it is necessary that some pollen
from the staminate blossoms should be placed upon the

THE FERTILIZATION OF FLOWERS 197

stigmas of the pistillate blossoms and should send down
through the style certain pollen tubes which come in contact
with these tiny ovules and fertzlize them. When they are
uous fertilized, the ovules will begin to develop into seeds.
The fact that these ovules are developing into seeds will
cause the surrounding ovary, which is the outer part of the
little cucumber or squash, also to develop, and the whole
will finally mature into a squash or cucumber with the seeds
inside.

If you look at these flowers again, you will see that the
pollen is sticky and well protected within the lobes of the
yellow corolla. You willalso see that the stigma is likewise
somewhat sheltered by the lobes of its corolla, and it will
easily be evident that there is no likelihood that the pollen
will either fall or be blown by the wind from one flower to
the other. How, then, is itcarried? This is a question you
can easily answer by a few moments’ observation on a
bright summer day. You will see great numbers of bees
of many sizes and kinds visiting all these flowers. If you
watch these bees, you will see that their bodies are more
or less dusted with pollen and that when they enter the
pistillate blossoms, some of this pollen is rubbed off upon
the stigmas. Consequently you will know, that while the
bees are gathering pollen and nectar to store up in their
hives or nests, they are also helping the plants by carrying
the pollen from one flower to another. This carrying of
the pollen from stamen to stigma is called pollination, and
the bees which thus bring about this pollination are called
pollenizers or pollinators.

If you examine many strawberry blossoms, looking es-
pecially'to see whether they all have about the same num-
ber of pistils and stamens, you will probably find that
upon some plants the flowers possess both sets of these

198 FARM FRIENDS AND FARM FOES

organs, while upon other plants you will find that the
blossoms have an abundance of pistils, but very few sta-
mens. If you think of this condition for a moment, you
will easily see that in the case of the latter, pollen must be
brought from those flowers having many stamens, if the
little ovules are
to be fertilized and
the seeds to de-

THE :

4 INSECT POLLENIZED velop.
Staminate Pistillate If you watch a
strawberry bedfor
STRAWBERRY a few moments

some bright day in May, you will have no trouble seeing
how this pollen is transferred from one blossom to the
other, for you are very likely to find a great many insects
attracted by the white petals of the strawberry blossoms,
gathering, perhaps nec-
tar, perhaps pollen, per-
hapsboth. Most ofthese
insects will be small bees,
possibly the common
honeybees, in case there
are hives of these near
at hand. Should you INA
follow a single bee as she
goes from flower to
flower, you would prob-
ably find that she often
passes from a_pollen-
bearing blossom to a
pistil-bearing blossom,
and after she has thus visited such a flower, if you
would look through a lens at the stigmas, you would

THE FERTILIZATION OF FLOWERS 199

doubtless see that a good deal of the pollen had been left
upon these.

You certainly should be now in a position to understand
what is constantly happening in all strawberry beds. The
bees are busily at work carrying pollen from blossom to
blossom, and thus causing the fertilization of the little
ovules and their development into seed. This growth of
the seed upon the surface of the future berry causes the
parts beneath the seeds also to develop into the luscious
fruit.

You can easily prove that this development of the berry
will not take place unless the seeds are fertilized by the
pollen. For if you cut off the upper part of the pistils
upon one side of the berry as the petals are unfolding, so
as to remove the stigmas, and then watch what happens,
you will be likely to find that one side of the berry which
is left to be fertilized by the bees will develop and that the
other side will not develop. You will thus have been the
cause of forming an abnormal berry of very little value,
but I hope you will have proved to yourself that the bees,
which are thus making possible our crops of strawberries,
are farm friends, without which we should fare badly.

CROSS-FERTILIZED FLOWERS

It is evident that in the case of the squashes and cucum-
bers, as well as of the strawberries, the pollen that occurs
upon the stigmas of a seed-bearing flower must come
from another flower. When pollen is thus carried from
one flower to another, the blossom is said to. be cvoss-
pollenized and the ovules as a result are cross-fertilized ;
that is, the ovules are fertilized by pollen from another
blossom which is usually upon another plant. When a
flower is pollenized and fertilized by the pollen from its

200 FARM FRIENDS AND FARM FOES

own anthers, it is said to be sedf-pollentzed and the ovules
are said to be self-fertilized.

As a matter of fact, the great majority of flowering
plants are cross-fertilized. Many of them have special
devices for preventing self-pollination. These devices
include the separation of the stamens and pistils in differ-
ent flowers, as in the case of the squashes-and cucumbers,
the maturing of the stamens and _pistils at different times,
or a difference in length of stamens.and pistils which pre-
vents the pollen from getting upon the stigmas. One of
the commonest methods that nature employs in preventing
self-fertilization is in rendering the pollen incapable of
fertilizing the ovules of the flower in which it developed.
Such flowers are said to be se/f-stertle, and‘ very commonly
none of the pollen upon a plant is able to fertilize the
ovules of any of the flowers upon that plant. Not only
this, but in many cases the pollen of a certain variety of
apple, pear, or plum is incapable of fertilizing any other
flowers of the same variety, even upon different trees.
In such cases the whole variety is said to be self-sterile
and must be pollenized by flowers of some other variety.

The discovery that a large proportion of the varieties of
tree fruits are self-sterile is one of the most important re-
cent developments in our knowledge of fruit growing. It
has been observed for a long time that the variety of plums
called the Wild Goose, when planted alone, will not set fruit,
even though there be many trees near together. It had
also been noticed that when other varieties of plums were
planted near the Wild Goose trees, the latter commonly
produced abundant crops. An investigation of the cause
of this, undertaken by M. B. Waite, of the United States
Department of Agriculture, showed that this lack on the
part of the Wild Goose trees was due chiefly to the fact

THE FERTILIZATION OF FLOWERS 201

that the variety is self-sterile, and requires for the develop-
ment of fruit the transfer of pollen from some other sort of
plum.

Other investigators have also made further studies of the
subject, the more important of these having been made by
Bailey, Fletcher, Kerr, and Waugh, with results which are
of great importance. to every fruit grower.

It has been pretty conclusively shown that in the case of
a large proportion of orchard fruits, a much more abundant
crop is produced where cross-pollination with another va-
riety takes place. It has also been shown that in many
cases there is a decided increase in the size of such fruits.
This increase is so marked that it is well worth while
for any fruit grower to take it into consideration in plan-
ning his orchard. The increase in size is believed by
Fletcher to be due to the fact that “the foreign pollen gen-
erally stimulates the fruit to a better growth, because it is
more acceptable to the pistils, not because it carries over
the size-character of the variety from which it came.”

In selecting varieties ‘of fruit trees with reference to
cross-fertilization it is. important to choose those which
blossom at the same time.

AGENCIES THAT CARRY POLLEN

There are three ‘principal agencies concerned in bring-
ing about the cross-pollination of plants. These are:—

I. The wind which carries the pollen for a large propor-
tion of the forest trees that blossom early in spring, but
which apparently has comparatively little to do with the
.cross-pollination of the flowers of most fruit trees and cul-
tivated plants. Such plants are said to be anemophilous or
wina-loving plants,

202 FARM FRIENDS AND FARM FOES

2. Certain birds, especially humming birds, which carry
pollen from flower to flower for a comparatively few species
in temperate regions, although apparently in tropical re-
gions there are many species so pollenized. Such plants
are said to be ornimophilous or bird-loving plants.

3. Insects of many kinds, especially bees, wasps, butter-
flies, and flies, which carry the pollen for the great majority
of flowering plants and in so doing confer an inestimable
benefit upon mankind. Such plants are said to be ento-
mophilous or insect-loving plants.

LEG OF BEE 5

CHAPTER XVII

The Insect Pollinators

By far the most important insect pollinators of cultivated
crops are the bees of the order Hymenoptera. The bees
form a superfamily called Apina, the members of which as a
rule are known by the fact that under a lens the hairs which
cover their bodies are seen to be provided with many minute
barbs. In most cases, also, the first joint of the hind tarsi
is expanded and hairy, being adapted to carrying pollen.
The tarsi are the short joints at the ends of the legs, and
the first is next to the second large joint of the legs, which
in a great many bees is especially developed into a so-called
pollen basket. This may readily be seen by examining the
hind legs of a bumblebee or other large bee. The barbed
hairs over the body are obviously an adaptation for carry-
ing pollen, and they enable these insects to become the
most efficient of all pollen carriers.

The bees, as a whole, are divided into two great groups
or families — the short-tongued bees (Andrenidz) and the
long-tongued bees (Apidz).

The short-tongued bees collect nectar and pollen from a
great variety of flowers, but they are not able to insert their
tongues into the long tubes of flowers in which the nectar
is deeply concealed. These bees, for the most part, build
their nests in the ground, burrowing holes into which they
carry a mixture of nectar and pollen upon which the larval
bees develop. Most of these short-tongued bees are very
small, and many of them may readily be found by a few

203

204 FARM FRIENDS AND FARM FOES

minutes’ inspection of flowers in which the nectar is easily
accessible.

The long-tongued bees may for our present purpose be
arranged into two principal groups, those that live solitary
lives and those that live social lives. The former are
comparatively few and so are of little importance as
pollinators of cultivated crops. One of the most distinc-
tive forms is that of the Leaf Cutter Bees, which have the
curious habit of cutting out pieces of leaves, to use in
building their nests. Roses and other plants often show
leaflets in which a rounded piece has been neatly cut out.
This is generally the work of one of these Leaf Cutter
Bees. These insects may be recognized from the fact
that the.under side of the body is covered with a brush of
hairs, which is used in collecting the pollen for provision-
ing the nests.

SocraL BEES

But the insects to which mankind is indebted beyond all
others for carrying pollen are the social bees, of which the
familiar Bumblebee and the domestic Honeybee are typical
examples. These bees live in colonies, a single colony
often consisting of a vast number of individuals. To a
large extent these insects have at least three distinct forms
in each colony. In addition to the true males and females
or the drones and queens, there. are great numbers of
workers, which are generally smaller in size and which
do most of the work of gathering nectar and pollen to
provision the nests with honey and bee bread.

The yearly cycle in the life of the Bumblebees furnishes
a good illustration of the habits of the social bees. Early
in spring you may often find the large queen Bumblebees
flying slowly about close to the surface of the ground in a

THE INSECT POLLINATORS 205

more or less zigzag fashion. They often alight and explore
some nook or. cranny that seems to promise a favorable
situation for a nest. These. queen Bumblebees are the
only kind that have been able to live through the winter,
and they have been sheltered in some deserted mouse nest
or similar covering.
_ When the queen Bumblebee finds a place that she thinks
suitable for a new nest, she adopts it for the home of her
future colony. Then she flies to the early spring flowers
and gathers nectar and pollen which
she brings to her nest and of which |
she forms little balls of. ‘bee bread.” -
This consists simply of a sort of paste |
made by mixing honey and pollen |
together. Upon each of these food |
balls, the queen bee deposits an egg: |
Very shortly each of these eggs -
hatches into a tiny footless larva that ee eee
feeds upon the bee bread and gradu-_ yinp Lacs
ally increases in size. Before very
long it becomes full-grown as a larva and changes to a
pupa or chrysalis, and a little later into an adult Bum-
blebee. These adults are smaller than the queens and are
the first of the season’s broods of worker Bumblebees.
These worker bees soon undertake a large part of the
care of the colony. They form the curious and character-
istic cells which are found so abundantly in Bumblebees’
nests late in summer, and they gather nectar and pollen
for the food of the young. The queen bee is thus left
free to deposit eggs for more broods of future workers.
Thus the colony passes through the summer, constantly
increasing in numbers.and all working together for the
good of the great bee family. They visit flowers of many

|
|
|
|

206 FARM FRIENDS AND FARM FOES

different sorts, especially those in which the nectar is
deeply secreted, as they are able to reach such nectar by
means of their very long tongues. They go about from
day to day, performing for mankind a service of inesti-
mable value and deserving his support and protection.

Toward the end of summer a brood of males and females,
or drones and queens, is developed. These come forth
late in summer or early in autumn, visiting flowers freely
along with the workers. All, however, except the queens,
perish when cold weather comes, and only such queens as
find adequate shelter are able to live through the winter to
begin again the cycle of the colony.

HoONEYBEES AND RELATED INSECTS

There are many kinds of wild bees, besides the bumble-
bees, which are useful in the pollination of crops. In
many thickly settled communities, however, these are not
so important as are the familiar hive bees, which, from
the point of view of usefulness to man, have the great ad-
vantage that they can be introduced into cleanly cultivated
regions where there are comparatively few places for wild
bees to breed. In many greenhouses, hives of bees are
regularly kept to bring about the pollination of cucumber
crops, a process that formerly required much hand work on
the part of men. Outdoors in large orchards, such hives
seem almost as essential for insuring the cross-pollination
of the millions of flowers to be found upon. the hundreds or
thousands of apple trees. These bees, of course, have the
additional advantage that they furnish honey to the owner.

There are many other members of the order Hymenop-
tera, which may commonly be found upon the flowers of
plants, seeking nectar or pollen, or both. The wasps,
hornets, yellow jackets, sawflies, and ichneumon flies may

THE INSECT POLLINATORS 207

all be found at times upon flowers, either wild or cultivated.
So far as cultivated crops are concerned, however, these
insects are much less important than are the bees, both on
account of their smaller numbers and the lack of barbed
hairs upon their bodies for catching and carrying the
pollen.

TWwo-WINGED FLIES

In the great order of two-winged flies (Diptera) there
are hundreds of species that freely visit flowers. Some
come for nectar, some for pollen, some for both. The legs
and bodies of many of these flies are furnished with hairs,
to which the pollen becomes attached and by means of
which it is carried from the anthers of one blossom to the
stigmas of another. These flies, as a rule, however, visit
those flowers in which the nectar is more or less exposed
in shallow cups, and, except perhaps in the case of certain
fruit crops, they are not nearly so important as pollinators
as are the social bees.

BuTTERFLIES AND MoTHS

In the great order of scale-winged insects, the moths and
butterflies (Lepidoptera), the great majority of species are
especially adapted to living as adults upon the nectar of
flowers. Consequently, there are many plants the blossoms
of which are especially adapted to cross-pollination by
means of butterflies or moths. These insects have long
sucking tubes, each of which is commonly coiled like a
watch spring on the -under side of the insect’s head. When
the butterfly or moth visits a flower, however, it uncoils the
tongue and projects it forward to reach the nectar of
the blossom. Often these tongues are of extraordinary
length, and so it is not surprising to find that the flowers

208 FARM FRIENDS. AND FARM FOES

especially adapted to the visits of moths and butterflies
commonly have their nectar deeply. concealed where it
cannot be reached by most other insects.

The great group of hawk moths or sphinx moths is one
of the most interesting from the point of view of pollina-
tion. By examining a beautiful Easter lily, one can readily
see the relation between these moths and the pollination of
such flowers.

“Tf you remove one side of the white flower cup, you
will see that the pistil consists of a long style running the
whole length of the flower, with the sticky stigmas at the
end. Grouped on the sides are the stamens, which also
have long filaments tipped with the anthers at the mouth
of the flower. Evidently no other insects can get the
nectar at the base of the cup; the sphinx moths are the
only ones adapted to derive benefit from such a blossom.
But for them the adaptation is perfect. The tongues of
the larger species will reach the honey, while their heads
come in contact with the anthers or. stigmas and perform
the pollenizing office.

“These moths are not day-fliers: they appear at dusk,
and during the early evening they shoot like meteors from
blossom to blossom, hovering hawklike in the mouth of
the flower, while the long tongue is inserted to extract the
hidden nectar. The immaculate whiteness of the lilies
renders them conspicuous in the twilight: they then shed
their perfume most abundantly, and, in some species at
least, produce the most nectar. These methods the lily
has developed to attract her pollen-carrying guests. The
latter also are assisted in the adaptation ; their long tongues,
the shape of their heads, their large eyes, all are useful to
the lily, while the swiftness of their flight and the business-
like way in which they utilize the few hours during which

THE INSECT POLLINATORS 209

they are abroad enable them to pollenize a large number
of blossoms in a short time.” ?

Some of the other lilies show similar adaptations to the
visits of sphinx moths, and many of the honeysuckles and
other flowering plants are adapted to pollination by such
visitors.

1 Weed, Ten New England Blossoms.

EASTER LILY

210 FARM FRIENDS AND FARM FOES

OBSERVATIONS FOR PUPILS

THE APPLE
A

1. Make a careful study of some apple blossoms. See if you can
identify all of these parts : —

_ The calyx lobes, which represent the sepals.
~The petals.

The stamens, each with filament and anther, the latter containing
pollen.

The pistils, united in the ovary, with the lower part of the styles
also united and bearing a fringe of hairs, then separating and
each having the stigma at the top.

The nectar cup on the top of the ovary.

z. See if you can determine how the nectar is protected from ants
and wingless insects by the palisade of filaments around the outside and
the hairs upon the united styles in the middle.

Thrust a sharp pencil point down through the hairs to see how the
long-tongued bee could get at the nectar while the short-tongued ant is
excluded from it.

3. Watch the apple trees on a bright day to see what sorts of insects
you find visiting the blossoms.

Make a list of as many different kinds as you recognize. Are
any of the bees collecting honey? Can you see them thrust their
tongues down to get the nectar ?

4. When it rains much of the time during the blossoming of the
apple trees, are the bees able to carry the pollen as well as when the
weather is fair ?

B

1. Tell or write a little story with this title : The Mission of the
Apple Petals. Follow some such outline as this : —

The pistil in the bud.

The nectar cup that it covers.

The purpose in attracting the bees.
The carrying of the pollen by the bees.
The fertilization of the flowers.

The falling away of the petals.

The development of the fruit.

THE INSECT POLLINATORS 211

2. If your story is written, illustrate it by such drawings of petals and
flowers as seem to you desirable.

3. Read: —

The Pollination of Pomaceous Fruits, Yearbook Reprint 157. |

THE CHERRY AND THE PLUM

Make a study of the structure of the blossom and its relation to
insect visitors in the case of the cherry or the plum. Follow. in a
general way the outline given above for the apple.

THE STRAWBERRY
A

1. Examine a number of strawberry blossoms and see if you can find
some in which there are many pistils and but few stamens, and others
in which there are both pistils and stamens in abundance.

2. Watch the flowers ona bright day to see what insects are visiting
them. Can you tell whether the insects are gathering nectar or pollen
or both. Do you see any pollen on the bodies or legs of the bees ?

3. Watch a bee carefully as it goes from one flowertoanother. Would
it be likely that some pollen would be brushed upon the stigmas as the
bee gathers nectar ?

4. How does the length of the blossoming period of the strawberry
compare with that of the apple? Are there more days for the bees to
cross-pollenize the strawberry than the apple ?

5. Tie a bit of mosquito netting or cheesecloth over one of the
pistillate strawberry blossoms before it opens so as to exclude any insect
visitor. See if a well-developed strawberry is formed after the petals
fall off.

B

1. Tell or write a little story with some such title as this : The
Strawberry and the Bees. Show how much we owe to the bees for
carrying the pollen from flower to flower.

2. Illustrate your story with drawings of bees and strawberry blos-
soms.

CUCUMBERS AND SQUASHES
A

1. Examine carefully all the flowers upon a single long stem of a
cucumber, squash, pumpkin, or melon plant. How many of the

212 FARM FRIENDS AND FARM FOES

blossoms are pollen-bearing or staminate, and how many are seed-
bearing? You may know the latter by the little fruit below the flower.

z. On a bright day see what kinds of insects are visiting the
flowers. Are they mostly bees? Do you find any bumblebees? Watch
one of the bees as it comes out of a pollen-bearing blossom and see if
you can see any pollen upon its body.

3- Watch one of the bees as it leaves a pollen-bearing blossom.
Do you find that it ever goes to a seed-bearing blossom? See if any:
of the pollen is rubbed from the body of the bee upon the stigma of
the flower.

4. See if any bees are at work on damp days when there is a little
mist or rain in the air. If any bees are at work, what kinds are they?

B

1. Write or tell a little story with this title: The Pollination of the
Squash Blossom. If it isa cucumber you observed, make it: The Pol-
lination of the Cucumber Blossom.

Follow this outline : —

The pollen-bearing flower.

The seed-bearing flower.

The need of the transfer of pollen.

The nectar that attracts the bees.

The color that advertises the nectar.

The bees that carry the pollen.

The wilting of the pollen-bearing blossoms.
The growth of the fruit.

2. Make a drawing of the side view of each kind of flower, and, if you
have time, a longitudinal sectional view of the seed-bearing ovary.

PART III

FRIENDS AND FOES AMONG THE
FUNGI

THE BOOKLET ON FUNGI

In addition to the drawings and written pages suggested under Observa-
tions for Pupils it is easy to enrich the booklet on fungi by mounted speci-
mens of leaves and other parts of plants affected by various fungous
parasites. These occur everywhere in autumn, so they are very readily
obtained. They may be pressed for a few days between papers, changing
daily, and then mounted by strips of gummed labels. The name, locality,
date, and collector should be printed on each sheet.

CHAPTER XVIII
Mushrooms, Toadstools, and Molds

Every one is familiar with the peculiar umbrella-like
plants called toadstools and mushrooms, which may be found
abundantly during damp weather, especially inearly autumn,
in fields and woods. They differ from our common plants
in that they have none of the
green coloring matter called
chlorophyl by means of which
the higher plants carry on
the processes of their life.

These toadstools and mush-
rooms belong to the great
group of fungi—a group
which includes a large num-
ber of species of plants. The
fungi rank lower in the scale
of life than the trees and
herbs which we commonly
have in mind when we speak of plants, but they serve
many important purposes in the economy of nature.

If you will place a well-developed toadstool of the general
type of the specimen shown in the picture above in the
position in which it grew, upon a piece of white paper, and
leave it for a day or two, the paper will probably be covered
with a fine dark powder. A similar powder will be found
upon the thin plates hanging down from the upper part
of the toadstool. If some of this powder be placed under

215

216 FARM FRIENDS AND FARM FOES

a high power of the microscope, it will be seen to consist
of great numbers of very small, roundish particles. These
are the spores or reproductive bodies of the mushroom, and
they may be likened in their relation to the life of the
fungus to the seeds of the higher plants.

When these spores are produced by the toadstool out-
doors, millions of them are blown away by the wind, or
washed away by the rain. When one of them chances to
fall upon rich darth, it
sends out a little tube, in
much the same way that
a sprouting seed sends
out its germinating radi-
cle. After this tube has
grown between the soil
particles a little way, it
develops branches that
push about between the
decaying bits of organic

MusHROoM matter and absorb mate-

Soil washed from “ spawn " and a buttons,” rialsof growth from them.

eee ee Because. of this the toad-

stoolis called a saprophyte

—a plant living upon decaying organic matter. These

branches in turn send out other branches and thus form

the spawn, or vegetative portion of the fungus. This 1s
also often called the mycelium.

This spawn continues to develop beneath the surface of
the soil for a while, until at certain places there are special
-growths from each of which one or more toadstools are
produced, often appearing suddenly above the surface.

Each toadstool consists of a stem, above which is a
wide top suggestive of an umbrella. This top bears on

MUSHROOMS,, TOADSTOOLS, AND MOLDS == 217

the under side curious thin vertical plates, called gills or
lamelle. On these plates the spores develop, falling from
them to the ground or being blown away by the winds.
The plant has now fulfilled the purpose of its existence,
and it rapidly decays—a process much hastened by the
numerous insect larve that feed upon the inner tissues of
the fungus. .

On most toadstools and mushrooms there may be found
a ring of thin tissue with ragged edges, hanging from the
upper part of the stem. This is the remnant of a delicate
membrane, called the vel/um, or veil, which covered the
surface of the cap during its rapid growth.

Those species of these fleshy fungi which are not
poisonous and are good
to eat are called mush-
rooms, while the poison-
ous ones are commonly
called toadstools. No
general rule can be given
for distinguishing the
edible from the poison-
ous kinds.

Perhaps a clearer idea
of the relation between MYCELIUM OF THE COMMON MOLD

the mycelium of a fun- From the spore lying near the middle of the
. . figure, and strongly swollen, one sees the
gus and its repr oductive thick threads of the mycelium arise. From

spores may be obtained the level of the mycelium arise three verti-
P y cal, fertile stalks, a, 4, c, of which a is still

from the picture above very young and that at 4 is already produc-
of one of the common ing a case containing many spores. All

molds that grow upon aca aie

bread or other materials in dark, moist situations. The
branching threads of the mycelium are spread out over a
wide space. At certain points rise vertical columns. On

218 FARM FRIENDS AND FARM FOES

the top of these the spores are produced. Compare it with
an apple tree: the mycelium corresponds in a way to the
roots; the vertical column to the trunk ; the spores to the
seeds in the fruit.

Can you not see that this mold is really a plant, though
it lacks the green coloring matter of our more familiar
plants?

PaRASITIC FUNGI

The toadstools, mushrooms, and molds are all fungi that
live at the expense of dead or decaying plant or animal
materials. They are not of very great interest to agricul-
ture. I have described them here to lead to a clearer
knowledge of certain other fungi that are of exceeding im-
portance to growing crops. These are the fungi that develop
at the expense of the tissues of living plants; that is, they
are parasites rather than saprophytes. They bring disease
and death to many crops and cause the myriad forms of
fungous diseases that destroy millions of dollars worth of
farm and garden produce every year.

RA ge

A DYING MusHROOM

CHAPTER XIX

The Downy Mildews

THE group of fungi commonly called the Downy Mil-
dews includes several of the most destructive fungous
enemies of cultivated crops. These parasites grow at the
expense of the vital tissues of the host plants, penetrating
between the cells in all directions and sending into the
cells curious projections that absorb their contents. -They
produce summer spores in untold billions, to be widely
scattered so quickly that whole fields may seem to succumb
inasingle day. The technical name of the great group to
which they belong is Phycomycetes. ©

Potato BLIGHT

In America the Downy Mildew of the Potato probably
causes the greatest loss of any of these parasites, espe-
cially in the Eastern states. During recent years this
disease has been generally called the Late Blight to dis-
tinguish it from the Early Blight of Potatoes due to a
different fungus. This Late Blight causes not only the
death of leaves and stems, but also the decay of the tubers.
It destroys millions of dollars worth of potatoes.

To get an idea of what happens in a potato field when it
seems suddenly to blight, let us assume that we have be-
fore us a green and healthy plant in August. Its leaves
are busily engaged absorbing the sunshine and converting
the unorganized substances from the soil, moisture, and air
into highly organized materials. These it is sending down

219

220 FARM FRIENDS AND FARM FOES

through its lusty stalks to the little tubers at the ends of
the underground stems, there to be stored in cells as
starch. All over the surfaces of the leaves are the tiny
openings or breathing pores through which the air gets to
the leaf cells and through which the surplus water may es-
cape as vapor. The plant is
healthy and vigorous and ap-
parently enjoying its existence.

But one day a breeze springs
up that carries particles of dust
from field to field. In the dust
are many summer spores of the
mildew fungus, some of which
are caught on the surface of
the potato leaves. The breeze
is followed by a summer shower
that soon passes, leaving the
foliage wet with glistening
drops that reflect the hues of
the rainbow as the sun comes out again.

In one of these drops a Downy Mildew spore is held.
It needed only the moisture to cause it to produce curious
swarm spores that swim about in the water and finally
germinate, each by sending out a slender tube. The tube
lengthens, the end creeping along till it reaches one of the
open breathing pores. It enters this and then begins to
grow rapidly, sending branching threads between the leaf
cells in all directions. These threads form the mycelium
of the fungus. They send into the cells short suckerlike
branches through which the contents of the. cells are
absorbed. Thus the threads of the fungus penetrate
through all the tissues of the leaf. Finally they run
through the petiole to the main stalk and perhaps down

PoTATO LEAF AFFECTED WITH
LATE BLIGHT

THE DOWNY MILDEWS 221

the stalk to the forming tuber below. Wherever they go,
they cause the death of the cells of living tissue, breaking
them up, turning them brown, and causing a foul odor to
be given off. In the case of the stalks and tubers the
result appears as a sort of rot.

The prosperous, healthy plant is thus stricken with a
sudden sickness that may well be called a blight. The
tubers are no longer able to increase
in size through the addition of starch
cells. A field thus blighted is a
sight that may well bring dismay to
the owner who had hoped for a
bountiful harvest.

But the parasite is not yet done
with its stricken host. All this
growth of mycelium has been but
a preparation for the development
of the reproductive spores, just as ee ee

: ied: uw, spore; 4, spore
the growth of the mushroom myce- germinating; ¢, spore
lium beneath the soil surface is but a with germinating tube

. i entering breathing pore

preparation for the sending up of |

the spore-bearing mushroom. The mycelium in the leaves
‘sends out to the surface vertical branches that bear upon
their tips the tiny summer spores. These mature quickly
and are readily carried away by the slightest breeze. Thus
the disease is able to spread rapidly by means of the bil-
lions of spores produced. This development of summer
spores begins soon after the mycelium gets well started,
often before the whole leaf is affected. Many of these
spores are likely to be washed through the soil till they
reach the ‘tubers, and they may develop there, causing a
characteristic brown discoloration.

This fungus commonly passes the winter by means of

222 FARM FRIENDS AND FARM FOES

the mycelium in the diseased potatoes. When they are
planted, a new crop of spores apparently is produced,
either on the seed potato itself or upon the stalks and
leaves that grow from it. Many of the downy mildews
have special winter spores by means of which the fungus
lives from one season to another, but these seem not to
have yet been certainly found in this species affecting the
potato.

The best methods of controlling Potato Blight are the
planting of tubers from fields in which the disease was not
present, spraying with Bordeaux mixture, rotation of the
crop, and the selection of resistant varieties.

When a parasitic fungus attacks one plant, it is very
likely to attack other closely related plants. The tomato
is closely related to the potato. Consequently it does not
seem strange that there is a Tomato Blight caused by
the same fungus that causes the Potato Blight. It is
often destructive in wet summers in the Eastern states and
during damp winters in southern California. Rotation of
crops and spraying with Bordeaux mixture are effective
preventive measures.

OTHER Downy MILDEWS

A parasite closely related to the Downy Mildew of
potatoes is the Downy Mildew of Lima Beans. This at
times is very destructive in many parts of the United
States, sometimes greatly reducing or almost destroying
the crop. It appears as a thick white covering upon the
pods, injuring the tissues of the wall and often extending
the damage to the young beans inside. It spreads chiefly
by means of summer spores, and apparently passes the
winter in the seed in the form both of dormant mycelium
and of distinct winter spores.

*

THE DOWNY MILDEWS 223

The chief preventive measures are the planting on high
land of seed gathered from a field where the mildew was
not present, the rotation of the crop, the destruction of all
old bean vines, and spraying with Bordeaux mixture.

The Downy Mildew of the Onion is a widely distributed
disease that causes serious loss in some parts of the
United States nearly every year. It attacks the leaves,
at first causing a yellowish discoloration that may later
show the white threads of the fruiting fungus. Vast
numbers of summer spores enable the disease to spread
rapidly during the growing season, and well protected
winter spores enable it to live through the winter in dead
leaves or in the soil. These winter spores appear to be
able to survive in the soil for two years. Consequently a
crop rotation in which onions are not grown on the same
land oftener than once in three years is desirable. Clean
culture, burning of diseased leaves, and spraying with
fungicides are also helpful.

Another Downy Mildew is often destructive to cucum-
bers, melons, and squashes. It is likely to destroy the vines
in almost any region when warm damp weather favors its
rapid growth. It seems to do as much damage in the South
as in the North, or more, and it often appears as an active
epidemic quickly blighting the vines over great regions.
The white mildew that gives off millions of summer spores
shows on the under surfaces of the leaves.

Clean culture, burning or deep burying of infested plants,
rotation of crops, and spraying with fungicides are the chief
remedial measures against this disease.

Among the numerous parasitic enemies of the grape the
Downy Mildew or Brown Rot is at times one of the most
destructive. In its life history it does not differ essentially
from the other Downy Mildews. It reproduces in summer

224 FARM FRIENDS AND FARM FOES

by summer spores and passes the winter in the form of
winter spores. It attacks leaves, young stems, and green
fruits, causing a mildew-like growth on the former and a
brown rot of the latter. It is prevented by spraying with
Bordeaux mixture. ,

The Brown Rot of the Lemon has recently become a
destructive disease in California. The fungus attacks the
rind of the lemon, causing a brownish discoloration and a
characteristic odor. It is likely to spread through the fruit
of boxes in storage or in transit, so that it often causes
serious and unexpected losses. The spores are produced
on the ground and not on the lemons, but they often reach
the latter through the water in which the fruit is washed.
Consequently, one desirable measure of control is the disin-
fection of this water by the addition of a small amount of
formalin or some other germicide. Full details of treat-
ment may be found in the bulletins of the California Experi-
ment Station.

OBSERVATIONS FOR PUPILS
MusHROOMS

1. Bring in a fresh mushroom or toadstool. Compare it with the
picture on page 215. Do you see all the parts there represented?

2. Place a fresh mushroom upon a sheet of paper and leave over
night. See if there are spores on the paper in the morning. If so, ex-
amine under a microscope.

3- Dig up the soil at the base of the stem of a mushroom to see if
you can find the mycelium from which it developed.

4. Look in lawns and pastures to see the “fairy rings” of mushrooms
that so often occur. See if you can find out the explanation of the pro-
duction of such rings.

5. Draw a mushroom and label the parts.

THE DOWNY MILDEWS 225

Downy MILDEWS

1. Which of these diseases have you known to be present in-your
neighborhood?
Downy Mildew or Late Blight of the Potato.
Downy Mildew of the Tomato.
Downy Mildew of the Lima Bean.
Downy Mildew of the Onion.
Downy Mildew of Cucurbits.
Downy Mildew or Brown Rot of the Grape.
2. What preventive measures are used against these diseases in your
neighborhood?
3. Make sketches of leaves affected by the disease in the case of such
of these as you find.
4. Read Farmers’ Bulletin gr.

CHAPTER XX
The Smut Fungi

Tue Smuts form a distinctive group of parasitic plants
called by botanists Ustilaginales. The mycelium develops
in the tissues of the host plant and causes serious injury to
the parts infested. Spores are developed in the form of
the blackish powder so characteristic of Corn Smut and
Oats Smut. These primary spores germinate under favor-
able conditions and often bring about
the development of enormous numbers
of secondary spores.

Nearly every one is familiar with the
Loose Smut disease which so often
affects the heads of oats, causing them
to become masses of loose blackish
powder instead of healthy kernels of
grain. These black powdery masses
are composed of millions of the minute
spores by means of which the fungus
multiplies.

These spores appear on the plants when the oats in the
field are blossoming. At that time the seed envelopes —
which later form the “ chaff” — are spread apart, so that it
is easy for the spores to lodge inside them. There the spores
remain, even through the threshing process.

The spores that have thus been concealed beneath the
chaff remain in position until the grain is planted. The
moisture and warmth favorable to the starting of the seed

226

SMUT SPORIDIA
Magnified

THE SMUT FUNGI 227

also cause these spores to germinate. They send out
tiny tubes that penetrate the young oats plant. The threads
of the fungus thus get into the growing tissues where they
continue to develop by sending out numerous branches that
run through all parts of the stalk. An elaborate se is
is thus formed, and continues to
develop along with the growing
oats plant.

When the grain begins to send
out its heads, the fungus develops
a mass of thickened threads within
the florets. These threads soon
give rise to millions of blackish
spores that form the familiar pow-
der of smutted grain.

The spores of this fungus are so
minute that the number in a single
diseased oats head is almost incon-
ceivably great. It has been esti-
mated that a single cubic inch of
the smut powder would contain
64,000,000,000 spores. Of course,
most of these spores never develop.
With the lower forms of life, Nature produces vast numbers
of reproductive bodies, with the expectation, as it were,
that only a small fraction of a per cent will find conditions
suitable for continued existence.

Many experiments have shown that Oats Smut may be
prevented by soaking the seed in diluted solutions of for-
malin, thus destroying the spores that cause the disease.

There is another form of smut disease, which is more in-
jurious to wheat than this loose smut, called the Bunt or IIl-
smelling Smut, because it has a distinctly disagreeable odor.

228 FARM FRIENDS AND FARM FOES

With this malady the individual kernels of wheat are affected
rather than the whole head. Such kernels appear whitish
or bleached in contrast to the yellow of the healthy grains.

Corn SMUT AND ONION SMUT

The curiously swollen kernels on ears of Indian corn
affected by the Smut are probably familiar to every boy or
girl brought up in the country. The swelling is due to the
growth of a parasitic fungus that develops among the grow-
ing tissues, making the plant cells abnormal and finally
destroying them. In place of cells of healthy tissue enor-
mous numbers of tiny blackish spores are finally produced.
These are the reproductive portions of the parasitic fungus.

These blackish spores are so fine and light that they are
readily scattered by the wind or are easily floated from place
to place by running water at
times of rain or flood. Un-
:. der favorable conditions as
to warmth and moisture each
spore is able to germinate
en and produce other or second-

Corn SMUT ary spores, which in turn are
able to penetrate the tissues
of the young corn plant and start the disease anew.

The greatest injury by Corn Smut occurs in gardens
where corn is grown season after season and the smutted
ears are left upon the soil. The first step in prevention is
to destroy promptly all the parts of corn plants that are
producing the disease, thus checking the development and
dispersal of the spores. Rotation of crops is also helpful.

The sorts of Smuts with which most people are familiar
are those affecting grains in which the fruiting kernels show

THE SMUT FUNGI 229

the injury most plainly. Some parasitic fungi, however,
develop upon the leaves and stems of other plants. The
Onion Smut is one of the most important of these. It attacks
the leaves and bulbs of seedling onions, giving them a char-
acteristic blackish appearance, and often ruining the crop.
The spores develop secondary spores called sgoridia in
much the same way that other Smut diseases develop.

The Onion Smut is especially troublesome on land in
which successive crops of onions are grown. This is be-
lieved to be due to the presence of the spores in the soil.
Consequently, a wise crop rotation is the first preventive
measure. The spores are also easily carried from field to
field in the soil adhering to hoes or other tools. Conse-
quently, care should be taken fo prevent this, as well as to
prevent the washing of the spores from field to field. Clean
culture and the deep burying or burning of all infested
plants is desirable.

The Smut fungus apparently enters the seedling onions
about the time they come up, rather than later. Conse-
quently, onions started in special beds and transplanted are
seldom injured.

OBSERVATIONS FOR PUPILS

LoosE SmuT OF OATS

1. Have-you seen smutted oats heads in fields? How much damage
does the disease do in your neighborhood?

2. If there is a compound microscope in school, examine the spores
under a high power.

3. Bring ina diseased oats head which has not yet bur&t open; place
the stem in a bottle of water and watch it for a few days to see the pro-
duction of spores.

4. Make a sketch of a panicle of oats injured by Loose Smut.

5. Read Farmers’ Bulletin 250.

230 FARM FRIENDS AND FARM FOES

Corn SMUT

1. In your neighborhood, is Corn Smut more injurious to sweet corn
than to field corn? Is it more destructive in gardens where sweet corn
is planted in the same place year after year than in gardens where the
sweet corn is rotated with other crops?

2. At what time do the first black spores develop on the smutted
ears?

3- Do the people of your locality take pains to cut out and burn the
diseased plants?

4. Make a drawing of a diseased ear of corn. If there is a com-
pound microscope in school, make sketches of the spores as seen with a
high-power objective.

CHAPTER XXI

The Rusts (Uredinales)

Few fungous diseases are more widespread in the United
States or more readily found in any locality than the As-
paragus Rust. This fungus was described in Europe in
1805 and had doubtless existed for ages before that time.
As a serious enemy it first attracted attention in the East-
ern states in 1896. It spread westward so rapidly that in
1QO1 it was very destructive in California. Since then it
has been generally recognized as the worst obstacle to as-
paragus culture.

In a way the life history of this rust is typical of the
great family to which it belongs. It passes through the
winter in characteristic spores attached to old leaves and
stalks, or lying loose upon the soil surface. These are
called the Winter Spores or Zeleutospores. They are
stalked, double-celled spores of curious and characteristic
form.

In spring these teleutospores germinate as they lie upon
the ground or upon the standing or fallen asparagus stalks.
The contents of each cell break through the cell wall and
run out in the form of a long tube. At the end of the
tube four partitions develop, so that four distinct cells are
formed. Then the material in each cell is sent out to form
a tiny secondary spore or sporidium (plural sporidia).

These sporidia are so small and light that they are easily
blown about by the wind. When one of them chances to
alight upon the green surface of a young asparagus plant

231

232 FARM FRIENDS AND FARM FOES

wet with dew or rain, it sends out a germinating tube that
penetrates the outer skin, generally through a breathing
pore, and starts a growth of fungus threads or mycelium
inside. These threads continue to grow and push in be-
tween the green cells of the leaf or stem, absorbing nourish-
ment from them.

After a short time the early spring mycelium has absorbed
so much material from the green cells that it is able to de-
velop a new set of spores. A special growth of the fungus
threads occurs at certain places just below the outer skin,

wee

SPORE GERMINATING WITH TUBE GERMINATING TUBE AMONG

ENTERING SYTOMATA; SEEN CELLS OF LEAF; SEEN FROM
FROM ABOVE SIDE

which becomes swollen with light green spots. Soon the
skin breaks apart and the fungus threads produce great
numbers of small round spores. The.small swollen places
where these spores are produced are called eczdza (singular,
@cidium), and the spores produced in them are called @cid-
zal-spores or spring spores, because they develop in spring.

These spring spores are scattered broadcast by the wind.
When one of them chances to alight upon the green surface
of a moist asparagus plant, it sends out a germinating tube
that penetrates'the tissues in much the same way that the
germinating tube of the sporidium did at the beginning of
the season. On the inside the germinating tube continues
to grow, forming new fungus threads that absorb the life

THE RUSTS 233

substance of the previously healthy cells. After a time
this mycelium is ready to produce spores again, and it
causes more tiny swellings upon the green surfaces of leaves
and stems. The skin of the swollen dots soon breaks apart,
revealing swarms of tiny rust-colored spores. These are
the wredospores or summer spores. They give the famil-
iar rusty color to diseased asparagus plants. They are pro-
duced in untold billions, to be scattered by the wind from
plant to plant and from field to field.

When they alight under conditions favorable to growth,
they start the disease anew. These summer spores are the
chief means for the general dispersal of the rust. Like
the spores produced in spring, they are unable to survive
long in a condition to germinate.

As autumn comes on, if the asparagus host plant becomes
weakened from any cause, the mycelium in the leaves and
stems produces yet a third kind of spores — the black rust or
winter spores with which our little story began. These
are called teleutospores: they develop in great numbers in
swollen pustules, their black color giving this stage the
name black rust to distinguish it from the orange rust of the
uredospore stage. -

These two celled teleutospores have comparatively thick
walls which enable them to survive the winter and start
the disease anew in the spring.

To summarize this story of the yearly cycle of the As-
paragus Rust :—

1. It winters in the black rust or teleutospore stage.

2. In spring the teleutospores germinate into secondary

spores called sporidia.

3. These sporidia infect asparagus plants and start in

the tissues of leaf and stem a growth of fungus
threads or mycelium.

234 FARM FRIENDS AND FARM FOES

4. This mycelium soon produces certain swellings or
pustules called zecidia from which spring spores or
zecidiospores are developed.

5. These zcidiospores spread the disease and start more
mycelium.

6. In summer the mycelium produces other pustules
from which the orange-colored summer spores or
uredospores are developed.

7. These uredospores spread the disease far and wide,
starting more mycelium from which more uredo-
spores are developed.

8. In autumn the mycelium in the tissues produces black
pustules from which the winter spores or teleuto-
spores are developed, thus completing the yearly
cycle.

Even in a slightly infested asparagus field-there are mil-
lions of teleutospores each spring. If each of these devel-
ops eight sporidia, there are of course enormous numbers of
the latter produced. These sporidia are short-lived, how-
ever, and each must soon find a living asparagus plant if it
is to start the disease anew. In established fields the
asparagus is cut and carried off almost as soon as it comes
up. Consequently, there is little chance for the rust to get
a foothold there. The asparagus plants upon which the
disease grows in spring are generally chance seedlings in
neglected corners or those newly planted fields in which
cutting has not been begun. It is important, therefore, to
destroy wild asparagus plants, for they help to tide the
disease over the weeks of spring.

CLovER Rust

The Clover Rust is similar in its yearly history to the
Asparagus Rust. It has the same three kinds of spores

THE RUSTS 235

succeeding one another, and is found upon both ted and
white clovers. It is a widespread disease, but seldom does
serious injury.

Another closely related fungus is Alfalfa Rust, but this
as a rule causes only a minorinjury. The pustules showing
the summer spores are likely to be found upon alfalfa leaves
at any time in summer.

The Rose Rust is still another species having a life story
similar to that of the Asparagus Rust. It is very frequently
found upon the léaves and stems of roses. Other rusts
occasionally occur upon beans and beets.

WHEAT STEM Rust

The Asparagus Rust is typical of the rusts that pass their
various stages upon one host. There are many others, how-
ever, in which the fungus develops part of the year upon
another host, so that the life history may seem even more
complex than that of the Asparagus Rust.

The Stem Rust of Wheat is a good example of a rust that
lives upon two hosts. Most people in regions where wheat
is grown are familiar with the slender black spots on the
leaves and stems of ripened wheat. Under a lens these are
readily seen to consist of teleutospores, similar to the teleu-
tospores of the Asparagus Rust. They serve as the winter
spores of the Wheat Stem Rust, living Henee the winter
wherever the straws may be.

In spring the teleutospores germinate by ee out
tubes, and these tubes in turn give rise to secondary spores
called sporidia exactly as in the case of the Asparagus Rust.

These sporidia are blown about by the wind.. If one
chances to light upon a moist barberry leaf, it germinates
and sends its fungus thread through a breathing pore into

236 FARM FRIENDS AND FARM FOES

the tissues of the leaf. Here it develops into a mycelium
that soon produces swollen orange-colored pustules, often
called cluster cups. In these pustules the mycelium
develops zcidiospores or spring spores which in turn are
blown through the air by the wind. This is often called
the cluster-cup stage of the rust.

Some of the zcidio spores are likely to find lodgment
upon the leaves or stalks of wheat plants. When moisture
from dew or rain is present, these will germinate and start
a growth of mycelium in the tissues. This mycelium will
soon produce a crop of rust-colored uredospores or summer
spores which scatter through the wheat fields and spread
the disease rapidly. This process continues through most
of the summer, and consequently this is the stage in which
the most damage is done by the rust fungus.

Finally, as the wheat matures the mycelium in the tissues
gives rise to the black rust or teleutospore stage. In this
condition it passes the winter.

YEARLY CYCLE OF WHEAT STEM RusT

I. Zarly Spring.
a. Teleutospores develop sporidia.
4. Sporidia are blown to barberry.
¢. Sporidia develop mycelium in barberry leaf.
II. Late Spring.
d. Mycelium in barberry leaf develops ecidiospores.
e. AEcidiospores are blown to wheat.
J. cidiospores develop mycelium in wheat.
HI. Summer. a
&- Mycelium in wheat develops uredospores.
4. Uredospores are blown to other wheat plants.
z. Uredospores develop myceiium in these wheat plants.
IV. Autumn,
J: Mycelium in these wheat plants develop teleutospores that
‘live through the winter.

THE RUSTS 237

If you will compare this yearly history of the wheat rust
with that of the asparagus rust, you will see that the chief
difference is that the sporidia develop upon another host
from which the ezcidiospores return to the wheat plant.
This difference is typical of many other rust fungi, and
special names are given to indicate the group to which the
various sorts belong :—

When the different stages of a rust fungus develop on
one kind of plant, it is said to be an autecious species; ex-
ample, the Asparagus Rust. ;

When the different stages of a rust fungus develop upon
two or more kinds of plants, it is said to be a heterecious
species; example, the Wheat Stem Rust.

The stem-rust on wheat and barberry is the typical ex-
ample of a hetercecious rust. It is interesting because of
the alternation of host plants and because all three forms
of spores are present. The Black Stem Rust, however,
often occurs in regions where barberries are either rare or
not found at all, and there is no doubt that the fungus can
live from year to year without going through the cluster-
cup stage on barberry. ;

OTHER GRAIN RuSTS

There are other rusts of grain even more destructive
than the Wheat Stem Rust. The Orange Leaf Rust of
Wheat is perhaps the worst of these. Technically it is
called Puccinia rubigo-vera. It is believed by good au-
thorities to be the most abundant of all grain rusts in the
United States. The uredospore form is the one generally
present, and in the South at least the fungus can live
through the year with no other spores present. --Teleuto-
spores have been found, but the zecidium stage is unknown.

238 FARM FRIENDS AND FARM FOES

The Crown Rust or Orange Leaf Rust of oats is an
abundant and widespread disease. Technically it is known
as Puccinia coronata. It has a life history very simi.
lar to that of the Black Stem Rust, the spring spores or
zcidiospores being developed upon buckthorn instead of
barberry. There seems little doubt, however, that the
fungus can pass through the as in the absence of this
zecidium stage.

Serious injury by. the Rust of Indian Corn is only rarely
reported, although the fungus is very common. It appears
on the leaves in brownish pustules of uredospores that
develop during summer. They are followed later in the
season by blackish teleutospores which live over winter
to start the disease anew in spring. This fungus is known
as Puccinia Sorghi.

CEDAR AND APPLE Rust

Another good example of a hetereecious rust is the one
that causes the “cedar apples” so often found on cedar
trees. These are curious little orange-colored balls that
occur along the twigs. In autumn and winter they have
smooth, rounded surfaces, but in spring they send out curi-
ous jelly-like masses about half an inch long. The teleu-
tospores germinate by sending out tubes that give rise to
secondary spores or sporidia. These sporidia are blown
about by the wind: such as fall on moist leaves of apple,
quince, or June-berry are likely to Bermingtc and start a
growth of mycelium within the leaf.

This mycelium soon gives rise to swollen pustules called
cluster cups or zcidia. In these millions of brownish
eecidiospores are developed. These are blown about by
the wind, and such of them as chance to light upon moist

THE RUSTS a 239

cedar branches germinate and start a growth of mycelium
in them. There appear to be no uredospores and no
spreading of the disease to other apple trees by the zcidio-
spores.

Consequently, in this case of the Cedar Apple and Apple
Rust we have but two distinct forms instead of the three
in the case of the. Black Stem Rust.

Thus: — ats ‘

1. Cedar Apples on Cedar.
Teleutospores develop sporidia to go to apple leaves.
2. Apple Rust.
A. Sporidia cause mycelium that produces zcidia
containing zcidiospores.
B. Ecidiospores go to cedar trees to develop cedar
apples. _

The mycelium in the cedar trees is perennial, living
from year to year and producing each sé¢agor new cedar
apples to send out sporidia. Consequently, the destruction
of the cedar trees is helpful in preventing the development
of the Apple Rust.

OTHER Rusts

The Orange Rust of blackberries, dewberries, and rasp-
berries is one of the most conspicuous and widespread
members of the family. It affects both wild and cultivated
plants and is found wherever these fruits grow. The con-
spicuous orange-colored ecidiospores appear in spring and
early summer,’and are followed later by a crop of uredo-
spores, and. these ‘in turn by the teleutospores. The
prompt burning of all infested canes is very desirable.
:ueAceharacteristic leaf rust,:known.technically as Puccenza
Pruni, commonly ‘affects plums, peach, and other stone

240 FARM FRIENDS AND FARM FOES

fruits. Itis seldom seriously destructive. The only spore-
forms known are the summer spores and the teleutospores,
both being of the brown color so general in the rusts.

During the last quarter of the nineteenth century the
Hollyhock Rust was very destructive in the United States.
It is still a pest, but less so than formerly when it caused
the culture of hollyhocks to be almost abandoned. There
is good reason to hope that resistant strains of Hollyhocks
will soon be developed.

The Hollyhock Rust appears as brownish pustules on
the under surface of the leaves. These contain an abun-
dance of two-celled teleutospores, and it is an interesting
fact that in this form of rust fungus this seems to be the
only form of spore that occurs. The teleutospores are
also remarkable for their ability to germinate at once instead
of resting through the winter as do most of the teleutospores.
Consequently, in this case the teleutospores are both sum-
mer spores and winter spores. The gathering and burning
of affected leaves is a helpful remedial measure.

OBSERVATIONS FOR PUPILS
Rusts

1. Which of the following rusts do you find in your neighborhood ?—

Apple Rust Hollyhock Rust
Asparagus Rust Oat Crown Rust
Bean Rust Plum Rust

Beet Rust Raspberry Rust
Clover Rust Wheat Leaf Rust
Corn Rust Wheat Stem Rust

2. Set aside a page of your booklet for three of the most important
of these rusts, and write a brief account of your observations upon each.

THE RUSTS 241

Perhaps this outline will help: —
The name of the disease.
Its abundance and the amount of damage it does.
The parts of the host plant most affected.
How it passes the winter.
The preventive measures used against it in your neighborhood.
3- Press a few leaves or stalks showing each of the rusts common in

your locality. Mount them on pages of your booklet.
4. Read the discussion of Grain Rusts in Farmers’ Bulletin 219.

CHAPTER XXII
The Ascospore and Other Fungi

A NuMBER of parasitic fungi are classified together in a
group called Ascomycetes because the principal spores are
developed in special tubular spore cases called ascz ; these
spores are called ascospores. They often serve as a means
by which the fungus passes through the winter; so they
are sometimes spoken of as wzuter spores. The fungus may
also develop more temporary spores which are often spoken
of as conidiospores or summer spores.

Brack Knot

Most schoolboys have seen the branches of plum and
cherry trees distorted by a black, knotty growth, having
the appearance of the picture on the opposite page. Wild
cherry trees very commonly show the injury, which is pro-
duced by the fungous disease known as the Black Knot.
The knots are caused by the growth of a parasitic fungus
in the twigs or larger branches. They first appear as
swollen places on the bark. These enlarge and cause
irregular cracks which are characteristic of the disease.
Finally the whole circumference of the twig may be affected
so that the part beyond soon dies.

During warm weather vast numbers of summer spores
are produced upon the bark of the knots. These give the
affected part of the twig a soft, velvety surface of a dark
olive color. These spores are blown from place to place.

242

THE ASCOSPORE AND OTHER FUNGI 243

Those that fall upon green and tender bark are likely to
germinate and start the disease again.

As cold weather approaches, the tissues of the outer bark
become much harder, with many little cavities inside. The
fungus produces within these cavities
spores that germinate the following
spring and start the disease anew.

The Black Knot affects most varie-
ties of plum-and cherry trees, both
wild and cultivated, and the spores
are easily carried from one sort of
tree to. another. Consequently, it is ;
important that in any locality all
traces of the fungus should be ex-
terminated. The cutting down of
worthless trees and the pruning away
of diseased branches are the first Brack Knot on WILD
steps in the control of Black Knot. BERG vanes

The. cutting out of the injury as sere
soon as it appears and spraying with fungicides will also
help to control it.

Peach LEaF CurL

Peach Leaf Curl is the name applied to a malady
that often affects the twigs and leaves of peach trees. It
causes the leaves to swell and curl soon after they expand
in spring, giving them an abnormal appearance that is at
once recognized as due to a diseased condition. The threads
of the fungus penetrate between the cells, growing rapidly
and causing a swelling of the tissues. The injured leaves
fall off in the spring or early summer. The twigs affected
also become swollen and distorted. Sometimes the disease
is confined to a branch or two, but frequently it involves

244 FARM FRIENDS AND FARM FOES

the foliage of the whole tree. In such cases the young
peaches are likely to drop off, and the crop be thus de-
stroyed. A new set of leaves will be put forth, but of course
the tree will be unable to produce the same season another
crop of blossoms and young fruit.

Fortunately this disease is readily prevented by spraying
with fungicides. Winter treatment with Bordeaux mixture
or the lime-sulphur wash is an effective remedy. This is
believed to be due to the fact that the spores of the fungus
pass the winter chiefly on the bark and buds of the trees,
so that they are killed by the fungicide.

PLum PockeETsS

The Peach Leaf Curl is due to the growth of a parasitic
fungus that belongs to the genus Exoascus. The fungi of
this genus cause abnormal growths of the plants they in-
fest. The curious “witches brooms” often seen upon birch
and other trees are due to these parasites. So, also, are the
strangely swollen plums often seen upon the plum trees and
commonly called Plum Pockets.

Young plums are generally affected by the Plum-pocket
disease. They become swollen, and when cut open are
seen to be hollow, with no pit. After a time they are likely
to be covered with a powder composed of the microscopic
spores of the fungus. These spores are widely scattered
by wind and rain, and presumably infest other trees, though
just how this is done is not now known.

It is known, however, that the threads of the fungus live
from year to year in the twigs and reach the young fruits
by growing through the blossom or fruit stalks. When a
branch is once infested, it bears the Plum Pockets year after
year, and all new twigs sent out by it beyond the point of

THE ASCOSPORE AND OTHER FUNGI 245

infection do likewise. Consequently it is evident that the
threads of the fungus grow along with the new growth of
the branch. The best remedy is to cut the branch off, some-
what below the point of infection, thus removing the dis-
eased tissues.

APPLE SCAB AND PEAR SCAB

The Apple Scab is one of the most familiar fungous
diseases. It appears as black spots, upon the surface of the
apple, and also
upon the leaves.
The spores of
the fungus that |
causes the dis- |
ease are pro-
duced in great
abundance on
these blackened
spots. They are
scattered far and
wide by wind and |
rain. Those that
lodge upon the leaves or fruits of apple trees germinate
during moist weather by sending out little tubes and thus
start the disease anew.

The growing portion of the fungus consists of brown-
ish cells. After atime the cells multiply and push out-
ward, exposing a surface in which the small oval spores
develop. These spores live through the winter on the
bark, twigs, and stored apples, as well as on the fallen
leaves and fruit.

The Apple Scab fungus not only causes the apples to
appear unsightly and injures them for food, but it also pre-

APPLE SCAB

246 FARM FRIENDS AND FARM FOES

vents them from growing to.as large a size as they would
if not affected. The extent of this dwarfing is illustrated
in the figure below. The disease may be prevented by
spraying with fungicides, the self-boiled lime-sulphur wash
being one of the best for this purpose. 2

DWARFED BY
APPLE SCAB

A closely related fungus causes the Pear Scab, which is
often destructive to certain varieties of pears. Its life his-
tory and control are practically the same as the Apple
Scab.

BirtER Rot oF APPLE

This disease causes losses of millions of dollars in the
United States almost every year. It is generally noticed
upon the fruit, especially as it approaches full size. Small
brownish spots may be seen at first; these gradually en-
large and commonly spread over much of the apple, caus-
ing it to fall) Many of the smaller fruits, however, re-
main upon the tree, shriveling to a mummified condi-
tion, in which they may hang to the twigs until the next
spring.

After the mycelium of the fungus has been growing in
the fruit tissues for a time, it develops upon the surface
characteristic blackish pustules in which great numbers of

THE ASCOSPORE AND OTHER FUNGI 247

spores are produced. These are scattered by wind and rain
and serve to spread the disease to new fruits. The myce-
lium gives a bitter taste to the parts of the apple near the
decayed spot.

This fungus is also
able to develop upon
the bark of apple
trees, where it pro-
duces dead blotches
called cankers. The

fungus apparently
passes the winter both
in these cankers and
in the mummied fruits, .
from which new crops |
of spores are pro-
duced in spring or
early summer.

The destruction of
mummied and fallen
fruits, cutting out and
burning all canker APPLES AFFECTED BY BITTER ROT
spots, and spraying
with fungicides are the means by which this disease may
be controlled.

Brown Rot or STONE FRuITS

The Brown Rot of peaches, plums, and cherries is one
of the most destructive diseases affecting fruits. It is the
commonest cause of the rotting of peaches or plums both
upon the tree before or during ripening, and also in the
baskets after picking. Its life history is similar to that of
the other fungi that cause plant diseases. The tiny spores

248 FARM FRIENDS AND FARM FOES

blown upon the damp fruit send out their germinating
tubes into the tissues where they grow, branching in all
directions. These branches absorb the cell contents. In

BROWN ROT SPORES
DEVELOPING
Magnified

this way the green tissues are broken
down, the light green color is turned
to brown, and the so-called rot ap-
pears. On the outside, the fruit first
turns brown in one or two places, then
more and more of the surface appears
affected, until finally the whole surface
shows the injury.

Soon after the fruit has thus be-
come discolored, it is likely to show
a curious velvety coating — more or
less grayish in color — that is made
up of millions of tiny spores. They

are produced by the threads of mycelium that have been

developing amid the tissues of the fruit.

Under the micro-

scope they are easily seen to resemble the figures below.

These spores are blown everywhere
by the wind and serve to spread the
disease very rapidly. A single affected
fruit may furnish millions of spores for
the wind to sow broadcast over the
surrounding country.

Unless the diseased fruits are re-
moved, many of them remain upon the
tree. They shrivel slowly into dry
and mummied fruits inside which the
threads of mycelium develop into
blackish bunches that correspond in a
way to winter spores and enable the

BROWN ROT
a, spores; 4, spores ger-
minating; magnified

fungus to survive the winter, and to produce a new crop

THE ASCOSPORE AND OTHER FUNGI 249

of spores in spring. These are likely to develop in the
tissues of the buds, blossoms, and young twigs, often caus-
ing serious damage.

Sometimes a curious mushroom stage of the fungus de-
velops in connection with the mummied fruits upon the
ground. Great numbers of tiny mushroom-like objects
develop from the mycelium. In these the winter spores
or ascospores are produced. - Apparently this stage is not
generally present, and is not necessary to the yearly cycle
of the fungus. :

Evidently one of the chief preventive measures with
this disease is the gathering of all the mummied fruits in
winter. By doing this, by thinnimg the fruit, and by spray-
ing with self-boiled lime-sulphur wash, most of the injury
may be avoided.

Pear LEAF BLIGHT

The foliage of pear and quince trees often becomes
spotted with brown in summer, and the spotting sometimes
is so extensive that the leaves turn brown and fall off.
When this occurs over the whole tree and is not at first
confined toa single branch, itis generally caused bya fungus
that attacks the leaves early in the season and continues
to develop until the end of summer, causing the disease
known as the Pear Leaf Blight. This fungus is a distinct
species of parasitic plant which at first causes small reddish
spots to appear upon the leaves. These spots gradually
grow larger and turn brown and often cause the whole leaf
to become brown and dead. The fungus also develops
upon the fruit, causing it to crack-open. Fortunately this
disease may be almost entirely prevented by spraying with
fungicides. ok TOS

250 FARM FRIENDS AND FARM FOES

STRAWBERRY LEAF SPOT

Every one who grows strawberries has noticed the brown
or reddish spots that appear upon the leaves, especially
late insummer. Theseare due toa fungous disease called
the Strawberry Leaf Spot. When the spots first appear,
they may be seen on the upper side of the leaf as small
dots of a purple or reddish color. They grow larger from
day to day; the central portions become brown in color,
while the margins retain their purple hue. The fungus
threads within the cells of the leaf generally affect a cir-
cular area, but frequently two or more centers of disease
will be sufficiently near each other to run together and
produce a large discolored blotch. Sometimes practi-
cally the whole leaf will be destroyed. The effect of the
disease upon the plant is to dwarf its growth and lessen
the fruit crop produced the succeeding year.

The Strawberry Leaf Blight may be prevented to a con-
siderable extent by spraying with the Bordeaux mixture.
Of course this cannot be applied while the berries are on
the vines. An excellent way to treat fruiting plantations
is to mow the vines after the berries are gathered, and
burn the ground over as soon as the leaves are dry. This
destroys the spores of the fungus and a new crop of leaves
will soon be produced comparatively free from blight,
especially if they are sprayed once with the Bordeaux
mixture.

The most successful growers of strawberries renew their
plantations every year, as they find it easier to set out a
new bed than to clean out an old one. When this method
is adopted it is seldom necessary to spray to prevent the
Leaf Spot.

THE ASCOSPORE AND OTHER FUNGI 251

Brack Ror or GRapEs

The Black Rot of grapes is one of the most destructive
plant diseases. It often causes the loss of a large part of
the crop in many vineyard regionsandis generally recognized
asadangerousenemy. The disease is caused by a fungus
that passes the winter in mummied grapes and is believed
to start in spring. from ascospores developed in them. It
appears in spring or early summer on young leaves and
branches, producing a brown discoloration. Later it shows
on the green grapes as brownish spots that spread over
the whole surface, finally producing a blackened fruit that
is appropriately described as affected by Black Rot.

On the surface of thesediseased grapes enormous numbers
of summer spores are developed. These are scattered
through the vineyard by wind and rain. Whenever one
rests upon a moist grape, it is likely to start a new disease
spot. In this way the disease may spread very rapidly
and cause great loss.

Clean culture and the destruction of dried grapes that
carry the fungus through the winter are desirable preven-
tive measures. Spraying with Bordeaux mixture has re-
peatedly been shown to be an efficient remedy.

CoTron WILT

Among the numerous enemies of cotton that -have be-
come seriously destructive during recent years, the Wilt
Disease is especially notable. It occurs over a large ‘part
of the cotton-growing region in the Southern states. The
affected plants are commonly stunted in their growth for
some time before they finally wilt as if from lack of water.
This is in fact the case, because the channels through

252 FARM FRIENDS AND FARM FOES

which the water reaches the leaves are clogged by the
growth of the parasitic mycelium.

The careful studies of several botanists show that the
fungus which causes the disease is commonly present in the
soil of cotton fields, where it is able to live long periods
as a saprophyte — getting the materials of growth from
decaying matter in the soil. When cotton is planted, how-
ever, it commonly becomes a parasite by invading the
tissues of the plants. The same or a very similar fungus
causes a wilt disease in watermelons and in the cowpea.

The only successful method of preventing this disease
now known is that of planting varieties that can resist
its attack. Much progress has been made in the develop-
ment of such varieties, and there is reason to believe that
still greater progress will be made in the near future.

THE PowpErRY MILDEWS

From midsummer until autumn one can find curious
whitish patches upon the leaves of a great variety of trees,
shrubs, and herbaceous plants. In some cases there are
but small spots of white upon the green background of the
leaf blade, while in others the whole surface may be whit-
ened and more or less powdery in appearance. As autumn
approaches tiny brownish or blackish spots appear upon
the whitened part. Such whitened leaves are very com-
mon upon lilacs, roses, willows, red maples, hardy phloxes,
and many other plants. They are especially likely to
be found on leaves growing in the shade. Such leaves
are probably affected by some form of those parasitic
fungi called Powdery Mildews. These are among the most

characteristic of the ascospore fungi, and form a very dis-
tinctive family.

THE ASCOSPORE AND OTHER FUNGI 253

If you will look through a lens or the lower power of a
compound microscope at one of the leaves thus affected,
you will see that the whitish appearance is due to vast
numbers of tiny threads that run over the surface of the
leaf, interlacing in a most interesting fashion. You will
find that the brownish or blackish dots are well-developed
spore cases — technically cailed perithecia — often having
curious projections from the outer wall. You can probably
see these cases in all stages of growth, from the young
whitish ones to the mature blackish ones.

If you place a few of the well-developed spore cases on
a glass slide in water, cover with another piece of glass,
and crush the walls, you will see the spores come out.
These spores are inclosed in smaller sacklike cases —the
asci.

When the leaves fall in autumn, these black spore cases
fall with them, and the spores inside remain over winter to
start the disease anew in spring. For this reason they are
often called the winter spores.

In spring or early summer the fungus threads get
started on the leaves. Unlike many other fungi, the
threads do not grow in or between the tissue cells of the
leaf, but they remain upon the outside and send curious
suckerlike projections in through the breathing pores of
the leaf to absorb food from the cells.

During summer, especially before the development of
the winter spore cases, the affected leaves often have a
powdery appearance. This is due to the development of
millions of tiny white spores. Certain threads of the my-
celium grow out at right angles to the surface of the leaf,
and on their ends produce spores that serve for the spread
of the fungus during the warm months. These are called
summer spores or conidia.

254 FARM FRIENDS AND FARM FOES

A great many different kinds of powdery mildews are
found upon wild and cultivated plants. One of the most
abundant of these is the Cherry Powdery Mildew, which
occurs also on apples and other fruits. It is especially de-
structive to young trees in nursery rows. The Gooseberry
Powdery Mildew is another widespread and destructive
disease. It is especially likely to attack English varieties ~
of gooseberries when grown in America. The Grape
Powdery Mildew is also more or less injurious over most
of the United States, and the Powdery Mildew of the Bean
is likewise widely injurious.

The powdéry mildews live externally upon the leaves
and stalks of plants more than is the case with most para-
sitic fungi. Hence we would expect that they could be
easily prevented by spraying with fungicides, and this is
true. These mildews are checked by applying almost any
of the fungicides.

OTHER Funcous DISEASES

A considerable number of fungous diseases are due to
parasites, the complete life histories of which have not yet
been discovered. Such fungi are commonly classified
under the heading Fungi Imperfecti or Imperfect Fungt.
The imperfection, however, is found chiefly in our lack of
knowledge. As the diseases are more carefully investi-
gated, the parasites are being transferred to the various
groups to which they belong.

The Potato Scab is one of the most important of these
diseases. It is caused by an inconspicuous fungus that in
freshly dug potatoes may often be seen as a coating of fine
white threads over the scabby surface. The disease occa-
sionally occurs upon beets and other root crops. Spores
are produced among these threads. It is now well estab-

THE ASCOSPORE AND OTHER FUNGI 255

lished that.on potatoes this disease may be prevented by
rotation of crops and soaking the tubers to be planted in a
solution of formalin of the strength of one ounce to two
gallons of water.

From the viewpoint of geographical distribution, the Early
Blight of the Potato seems even
more important than the Late
Blight. The former is distrib-
uted throughout the United
States, while the latter is chiefly
destructive in New York and
New England. The Early
Blight appears about the time
the plants blossom, showing as
small brown spots scattered over
the leaves. Sometimes the spots
enlarge and run. together into
blotches. The whole plant is
often killed long before its time,
so that the tubers in affected
fields are small, though there is
no rotting effect on account
of this disease. Fortunately,
spraying with Bordeaux mixture is an efficient preventive.

The Anthracnose of Beans is another widespread and im-
portant disease. It is familiar to most people who have
attempted to grow string beans, because the reddish brown
spots upon the pods are too conspicuous to be overlooked.
Sometimes the disease is called the Pod Spot. Such in-
jured pods are generally worthless, and the whole crop is
often ruined in wet seasons, for moisture is an important
factor in the development of the parasite.

When tthe pods are seriously affected by the fungus,

PoraTo LEAF AFFECTED BY
EARLY BLIGHT

256 FARM FRIENDS AND FARM FOES

the beans inside are also liable to be affected. If such
beans are planted, they are liable to start the disease in the
new crop. Consequently, the selection of seed from fields
or pods in which the fungus is not present is the most
promising preventive measure. It is also desirable to burn
infested vines after harvesting as well as to rotate the crop
and select for it high, well-drained land.

The Cotton Anthracnose is an important disease in
many Southern states. It occurs especially upon the bolls,
but also affects other parts of the plant. ‘The injury to
the bolls is suggestive of that upon bean pods, and the af-
fected bolls are likely to result in infected seed.

The Anthracnose of Raspberry and Blackberry is an-
other widespread disease. It produces characteristic red-
dish purple spots upon the young canes in spring and sum-
mer. The centers of the spots later become grayish white,
and the spots enlarge, often running together and forming
blotches. The spores are developed in dotlike elevations.

The best means of controlling this malady are found in
the removal of affected canes, frequent rotation of the
plantation, and spraying with fungicides. The self-boiled
lime-sulphur wash would seem worthy of trial in an ex-
perimental way.

Still another Anthracnose affects green grapes, producing
a characteristic injury that is sometimes called Bird’s-eye
Rot. It occurs upon leaves and branches as well as the
fruit, but is most destructive to the latter. The destruc-
tion of diseased portions is an important preventive measure.

CLUBROOT OF CABBAGE

This disease is caused by a low form of parasitic fungus
that is classed with the group of Slime Molds rather than

THE ASCOSPORE AND OTHER FUNGI 257

the Imperfect Fungi where the diseases discussed in the
last few pages are classified. The fungus causes strange
malformations of the roots of cabbage, cauliflower, and
other wild and cultivated members of the mustard family:
It reproduces by spores and is especially likely to deveiop
in acid soils. Consequently liberal applications of lime
and rotation of crops are helpful methods of preventing in-
jury. Especial care should be taken not to throw diseased
roots upon the compost heap. It is better to burn them.

OBSERVATIONS FOR PUPILS
Biack Knot

1. Is the Black Knot abundant in your locality ? Does it occur
upon wild cherry trees ? If so, upon what kind of wild cherries is it
most abundant — the choke cherry, the wild black cherry, or the wild
red cherry ?

z. Notice the difference between the dry or winter condition and
the velvety or summer condition of the knots. Feel the velvety coating.

3. If a microscope is available, look at the spores from the velvety
surface by means of a high power.

4. What preventive measures against Black Knot are used in your
locality ? Is there a law in your state requiring property owners to
destroy the knots ?

5- Do you think that the presence of this disease along roads and
fences and in dooryards is a reflection upon the efficiency of your school
as an agent for the common good ? If so, why not organize a campaign
of extermination against the Black Knot ?

6. Has one man a right to allow the spores of Black Knot to
develop on his trees to be blown to the trees of his neighbors ?

7. Make a careful sketch of a twig, showing Black Knot, for your
booklet.

POWDERY MILDEWS
1. Look at leaves of lilac, willow, and other plants to find those

affected by the whitish covering of the Powdery Mildews.
2. Bring such leaves to school and study them as directed on pages

258 FARM FRIENDS AND FARM FOES

253-254. See if you can distinguish the summer spores and the winter
spore cases.

3. Make a list of the Powdery: Mildew diseases that you know to
occur in your locality.

4. Make a list of remedies that are used in your locality to prevent
injury by these diseases. ;

5. Make sketches of the fungi as seen through the microscope, also
of leaves showing spots where the fungus is present.

CoTTon DISEASES

1. Learn what diseases are most destructive to cotton in your region.
Collect specimens. /
2. Read such of these references as your teacher directs : —
Farmers’ Bulletins 302, 333.

OTHER DISEASES

1. How many of the following diseases are you able to find in your
locality ? —
Peach Leaf Curl.
Plum Pockets.
Strawberry Leaf Blight.
Brown Rot of Stone Fruits.
Black Rot of Grapes.
Bitter Rot of Apples.
Apple Scab.
Pear Leaf Blight.

2. Write a short account of your observations upon three or more of
these diseases. This outline may help: —
The abundance of the disease. ;
The parts of the host affected: whether leaf, fruit, or bark.
How diseased leaves or fruits look.
How the fungus passes the winter.
Preventive measures.

3. Make sketches showing the characteristic appearance of each
disease you write about.

CHAPTER XXIII

Bacterial Diseases of Plants

THE microscopic one-celled plants called Bacteria or
Microbes are now known to be the cause of some of the
most destructive plant diseases. In a way the life history
of these bacteria is simpler than that of many of the fungi
affecting growing crops. The bacteria multiply chiefly by
a simple division of the cells, each single cell dividing into
two cells. This is a very rapid process, however, so that
when once within the tissues of a plant the disease-pro-
ducing microbes spread very quickly. Consequently, these
diseases are often called Blights. Another appropriate
name for some of them is Bacteriosis.

PEAR BLIGHT

One of the best-known and most characteristic of these
bacterial diseases is the Fire Blight of the Pear, Quince,
and Apple. The leaves on the branches affected by this
malady suddenly turn black as if injured by fire and hang
upon the twigs in this blighted condition for some time.

This Blight affects pear trees much more than apple
trees and is the most serious obstacle in the way of suc-
cessful pear culture. It is very generally known simply
asthe Pear Blight. It has been carefully studied by many
scientésts, so that the characteristics of the disease are well
known. The microbe causing the malady was named
Bacillus amylivorus by Professor T. J. Burrill of Illinois.

259

260 FARM FRIENDS AND FARM FOES

Drops of viscid liquid are commonly found along the
margin of the diseased areas of the bark. These are
swarming with the germs of the Bacillus. Bees and other
insects are attracted to these drops, sucking them up and
getting myriads of microbes upon their feet and mouth
parts.

Many bacteria multiply rapidly in sweet, jelly like liquids.
Such a liquid is found in the nectar cup at the base of the
pear blossom, and to a less extent on the end of the pistil
of the same flower. Should a bee
visit a diseased tree and get some
of the blight microbes upon its
feet or mouth parts, and then visit
the blossoms of a healthy tree, some
of these germs would probably be
introduced upon the nectar of the
latter.

Ctaw FRom Bee's Foor | When thus placed ina position
WITH BLIGHT Bacteria favorable to growth, the bacteria
Se ice) orem multiply rapidly, and follow down

through the stalk of the flower to
the twig. Here they continue to develop, and soon may
spread downward through the branch. As far as they go
they kill the tissues, causing blossoms, leaves, and twigs
to turn black.

The germs may also be introduced to new trees through
breaks in the bark or by the gnawings of insects. The
disease is more severe in trees that grow rapidly than in
those that grow slowly. Consequently cultural methods
that induce rapid growth are to be avoided. The prompt
cutting off and burning of all affected branches, taking
care that the germs are not distributed by saw, knife, or
shears, is the most effectual remedy.

BACTERIAL DISEASES OF PLANTS 261

Crown Gat DISEASE

It is now pretty well established that the widespread
disease of fruit trees called Crown Gall is caused by bac- -
teria. This has recently become one of the most destruc-
tive maladies of trees, having been widely distributed
through nursery stock before its real nature was discovered.
This disease appears in spring as an abnormal growth upon
the roots of apple, pear, peach, and other trees, as well as
those of blackberries and raspberries and various herba-
ceous plants. The growth continues through the season,
often forming large galls of varied shapes. Ordinarily
the growth ceases at the end of the first season, and the
gall later decays and disintegrates. New galls are likely
to appear the next season on other roots in large num-
bers, damaging the root system so badly that the tree may
finally die.

It is easy to see how readily soil could be inoculated with
crown-gall germs. If a diseased tree is planted and later
dug up, itis probable that millions of the spores will remain
in the ground. Consequently great care should be taken
not to set diseased plants, and if possible to get plants from
nurseries where crown gall is not present.

CaBBAGE Rot

The Cabbage Rot is another bacterial disease that has
been carefully studied by several scientists in widely sep-
arated regions. The malady is especially destructive to
cabbages, often ruining large fields. It also attacks caulli-
flowers, turnips, rutabagas, and various other plants of the
mustard family. It has been found on Charlock, a weed
belonging to this family, and probably occurs upon other
species.

262 FARM FRIENDS AND FARM FOES

The fact that the Cabbage Rot is caused by a bacterial
germ has been abundantly demonstrated. If you look
at cabbage leaves during a season of damp weather, you
will probably see a row of water drops along the margin
of each leaf. These have come out from small pores,
extending from the margin to the veins of the leaf. The
leaves are constantly giving off surplus water through
the pores; in dry weather the water evaporates as it
emerges, but in moist weather it remains to form the water
drop.

When one of the tiny bacteria carried in the air by the
wind happens to lodge in one of these water drops, it begins
to multiply, and soon develops in such numbers that the
bacteria enter the leaf through the water pore. Once in-
side, they travel down the veins, causing injury as they
go, until they reach the main stalk. They follow the large
channels in this stalk, and sometimes permeate the whole
head by pushing along through the system of veins.

The injury done by these myriads of microbes checks
the growth of the plant and finally kills it. The germs of
other microbes soon enter the injured tissues and ‘cause a
vile-smelling rot which effectually completes the work of
destruction. ;

While the Cabbage Rot Bacterium is able to invade
healthy plants through the pores, it is often introduced
also by the bites of insects. If an insect is feeding upon
a diseased cabbage, its mouth parts are likely to be more
‘or less covered with the disease germs. [If it then bites a
healthy plant, some of these germs will enter the tissues
of the latter, and the malady be started anew.

The disease has proved very difficult to overcome.
Crop rotation and clean culture are helpful, but they are
by no means always effective. The selection of healthy

BACTERIAL DISEASES OF PLANTS 263

plants from the seed bed is important. Warm, moist
weather is favorable to the development of the malady.
Duggar advises soaking the seed for twenty minutes in
formalin solution, one part to two hundred parts water.

OTHER BACTERIAL DISEASES

The Bacteriosis or Blight of the Bean and related plants
is another destructive disease. It affects especially the
pods, producing soft spots with a characteristic water-
soaked appearance. More rarely it attacks the stems and
leaves. Apparently the disease may be started through
infected seeds, so that care to select seeds from blight-free
fields is desirable.

The Bacteriosis of melons, cucumbers, and other vines
is still another destructive malady. The bacteria develop
in enormous numbers in the water channels of the plants,
thus preventing water from reaching the leaves, and caus-
ing the sudden wilting of the latter. Flea beetles, striped
beetles, and other insects help to carry the microbes from
plant to plant.

Corn and celery are both subject to bacterial diseases,
and cotton bolls are attacked by microbes that cause the
Cotton Boll Rot. Potatoes, tomatoes, and eggplants are
the victims of another bacterium that causes injury to
leaves and tubers or fruits.

OBSERVATIONS FOR PUPILS

PEAR BLIGHT

Have you ever seen pear trees injured by this disease?
. How did it show itself ?
Have you seen blighted apple branches?

. Read this reference : —
Pear Blight: Its Cause and Prevention, Yearbook Reprint 500.

Wh

CHAPTER XXIV

Preventives of Fungous Diseases

In a general way the methods used to prevent injury by
fungous diseases come under the head of preventives rather
than of remedies. Even in cases where an injured part of
a plant is cut off, the aim is to prevent further spread of the
disease within the tissues of the plant or to the tissues of
other plants. When the fungus has once invaded the cells,
there is little hope of remedy so far as the, affected part
of the host is concerned. In the case of the external
mycelium of the powdery mildews, however, the fungicide
may have a direct effect.

The various fungicides are really preventives rather than
remedies. They kill the spores or. mycelium threads upon
the outer parts of the plants treated, or they lie in wait to
kill whatever spores may come to seek entrance to the tis-
sues. The chemicals of the fungicides do not enter the tis-
sues of the host to destroy the fungus threads among thecells.

It is evident that the prevention of the ravages of fun-
gous diseases is a broad subject. Many ways will readily
occur to one who thinks of the myriads of parasitic fungi
and their varied host plants. These ways may all be
grouped, however, under two general topics : namely, (1)
the destruction of the parasite; (2) the prevention of its
growth upon or within the host.

PREVENTIVE MEASURES

Taking up the latter. topic first, we find that for many
‘fungous diseases the most important method of prevention
264

PREVENTIVES OF FUNGOUS DISEASES 265

lies in the selection of varieties or strains of varieties that
are able to resist the attacks of the parasite. In the case
of the grain rusts as well as of many other diseases, this
seems to be the only practical way of preventing injury.
It is of the greatest importance that disease-resisting sorts
be planted of all crops in which there is a variation in this
ability. Crop growers should always be on the alert to dis-
cover individual plants that are able to resist the parasites.
One may thus develop a strain of greatest value.

Some years ago an asparagus field in one of the central
Western states was struck by the asparagus rust. In the
great area of reddened plants, only one stood out green and
flourishing. Through some peculiarity of its life substance
it was able to resist the attacks of the fungus. The owner
had the good sense to see that this plant might be made
the parent of a resisting race. So he saved the seed,
selected the most resistant plants that grew from them, and
in a few years was able to introduce to the trade a valuable
variety.

Similar progress has been made in the selection of vari-
eties of cotton able to withstand the dreaded wilt disease
for which no remedy is known.

The selection of disease-resistant plants and the breeding
of new varieties from them is now occupying the attention
of many painstaking men. Much progress has already
been made, and we may soon expect great benefit from their
labors.

Anotherimportant method of preventing the growth of the
parasite upon its host is so to isolate the crop that the fun-
gus may not reach it. In the case of many diseases, the
spores of which are carried far and wide through the air,
this is not practicable. Many of the rusts, for example,
travel great distances on the wind, and thus reach crops

266 FARM FRIENDS AND FARM FOES

on new ground. In the case of many other diseases, how-
ever, the fungus remains in the soil from year to year, and
unless crop rotation is practiced, each succeeding season
is likely to show greater damage. This is notably true of
some of the smut diseases: a garden in which sweet corn
was grown for many years finally produced few ears that
were not injured. This fact makes more plain the lesson
of all good agriculture that a rotation of crops is- one of
the first essentials to success.

In general, good tillage and fertilization help to prevent
injury by fungous diseases. Many plants seem better able
to grow without damage by fungi when they are in a
vigorous condition. This is not always true, however, for
the very rapidity of growth in some plants produces condi-
tions favorable to the development of the parasite. Pear
trees of quick growth are much more liable to blight than
those of slower growth, and grains growing vigorously seem
to be more liable to injury by rusts than those of slower
growth. ;

Sometimes it is possible to exclude the germs of the para-
sites by mechanical means. The various mildews and rots
that affect grapes are readily excluded by fastening paper
bags over the stems soon after the fruit is set.

In many instances the easiest way to prevent the spores
of fungi from reaching new hosts is through the direct de-
struction of the fungus that produces the spores. This is
obviously a practical method that may be adopted under
‘greatly varying conditions. In general it involves clean
culture and the destruction of refuse materials upon which
spores may be developed. The plants of many crops may
continue to produce fungus spores after the fruits are
gathered, and the burning or deep burying of such plants
is very desirable. In the case of species of fungi that

PREVENTIVES OF FUNGOUS DISEASES 267 |

alternate from one host to another the destruction of one
form may prevent the development of the other. Thus,
the easiest way to prevent injury by apple rust is to cut
down the cedar trees on which the infecting spores develop.
In the case of others, the fungus may develop on wild
plants and the spores be carried to those cultivated. Thus,
in fighting black knot in plum and cherry orchards it. is
essential that the infested wild cherry trees in the same
locality be destroyed.

REMEDIAL MEASURES

The use of fungicides — or substances that kill fungi —
has recently become the most generally adopted method of
preventing these diseases. These substances are applied
to the surface of the soil, stems, foliage, or fruit, where they
may kill the spores present at the time and may also re-
.main for a considerable period in condition to destroy any
spores that subsequently alight.

The various salts of. copper are among the most impor-
tant fungicides. These are used in a great many ways, but
the most important combination is that.of copper sulphate,
commonly called blue vitriol with lime and water. This
mixture was first used in Bordeaux, France, to prevent cer-
tain grape diseases. So it is generally called the Bordeaux
mixture. It is now the most widely used fungicide and is
recognized as a sure preventive of many plant maladies.
The usual formula is : Copper sulphate, 4 pounds; unslaked
lime, 4 pounds; water, 50 gallons..

The application of Bordeaux mixture to apple trees often
causes a troublesome russeting of the fruit that lessens the
value of the crop. On this account, dilute lime-sulphur
washes are used in its place in many orchards.

Copper sulphate is also used in simple water solution.

268 FARM FRIENDS AND FARM FOES

For spraying dormant trees in winter or early spring, it is
used at the rate of one pound dissolved in fifty gallons of
water. For spraying trees in leaf it is used at the rate of
two ounces dissolved in fifty gallons of water.

Carbonate of copper is also used as a fungicide. It is
generally prepared as follows: Three ounces of the car-
bonate are to be dissolved in three pints of ammonia, the
whole then being added to a barrel of water. The pow-
dered carbonate dissolves more readily if it is first made
into a paste by mixing with water. One advantage of this
fungicide, which is used for the prevention of apple scab
and various mildews, is that, being a clear solution, there is
no clogging of nozzles, as sometimes happens with the Bor-
deaux mixture.

Sulphide of potassium or liver of sulphur is sometimes
used to prevent the mildew on the leaves and fruit of goose-
berries. Half an ounce is dissolved in two gallons of hot
water, and the solution when cold is applied to bushes in
the form of a spray.

Powdered sulphur, commonly called flowers of sulphur,
is valuable as a fungicide for some forms of fungi affecting
plants. It is used in California as a preventive of asparagus
trust. The fumes that rise from the sulphur on the hot soil
in sunshine kill the rust spores.

The lime-sulphur spray used as a remedy for scale in-
sects is also a fungicide. It has proved one of the best
remedies for peach-leaf curl, brown rot of stone fruits, apple
scab, and other diseases.

Solutions of formalin have been found of great value as
fungicides in the treatment of potato scab and grain smuts.
Fortunately, this substance is now taking the place of cor-
rosive sublimate—a poison too dangerous to use unless
absolutely necessary.

PREVENTIVES OF FUNGOUS DISEASES 269

CoMBINING INSECTICIDES AND FUNGICIDES

In many cases it has been found that a fungicide is also
of value as an insecticide, and vice versa. In others, it is
easy to add an insecticide to the fungicide solution, and thus
prevent both classes of injury by one application. A Bor-
deaux mixture with arsenate of lead added is the combina-
tion most frequently used in the past, but it seems likely to
be displaced by the combination arsenate of lead and the
lime-sulphur wash.

“ The successful orchardist of the future,” writes W. M.
Scott, “will be the man who, among other things, studies
the conditions existing on his own farm and sprays his
trees according to the needs of each variety for the control
of the particular troubles which occur. in his locality.
The course of treatment best suited for the orchards
of the Shenandoah Valley of Virginia may not neces-
sarily give the best results.in orchards situated east of
the Blue Ridge in that state, and again the treatment for
certain varieties of apples may be different from that re-
quired for certain other varieties growing in the same
locality. The course of treatment should be planned not
only with reference to the diseases to be controlled, but
also with reference to the probable effect of the fungicide
upon the fruit and foliage of the variety to be treated.
The Ben Davis, for example, is so seriously russeted by
applications of Bordeaux mixture that often most of the
fruit sprayed with this fungicide is rendered second class.
In Virginia this variety does not suffer materially from the
attacks of scab, bitter rot, or other serious fruit diseases, the
leaf spot which is easily controlled being its chief fungous
enemy. The Ben Davis in Virginia and in other similar
situations may therefore be successfully sprayed with a

270 FARM FRIENDS AND FARM FOES

weak fungicide which will control the leaf spot, sooty fungus,
and slight scab infections without injury to the fruit or foli-
age. The York Imperial is another variety which has no
serious disease of the fruit, and in addition it is not subject
to Bordeaux russet, so common on the Ben Davis, but the
foliage is susceptible to leaf spot and is often badly injured
by. applications of Bordeaux mixture.

“On the other hand, the Yellow Newtown is seriously
subject to the attacks of bitter rot and must be treated with
a strong fungicide, such as Bordeaux mixture, for the con-
trol of this disease. The fruit of this variety is susceptible
to Bordeaux injury, but since such injury is produced only
by the early applications of the mixture, the treatment may
be so planned as to avoid it. One of the lime-sulphur
sprays may be used for the first and second sprayings after
the petals fall, and Bordeaux mixture for the bitter rot
treatments which come later. These are the finer points
to be considered in connection with spraying, and the
orchardist who gives them due consideration will obtain
the best results in the production of good fruit.”

The National Department of Agriculture issues bulletins
giving precise directions for the preparation of fungicides.
These are frequently revised,.and should be obtained when
fungicides are to be prepared.

OBSERVATIONS FOR PUPILS

1. What methods of preventing plant diseases are employed in your
neighborhood ?

2. Do the more progressive farmers use the spraying machine or those
less progressive ?

3. Read such of these references as your teacher may request :—

Spraying for Cucumber and Melon Diseases, Farmers’ Bulletin 231. Fungicides
and their Use in preventing Diseases of Fruits, Farmers’ Bulletin 243. Insect and
Fungous Enemies of the Grape east of the Rocky Mountains, Farmers’ Bulletin
284. Grape Diseases on the Pacific Coast, Farmers’ Bulletin 30.

CHAPTER XXV

Fungous Diseases of Insects

Dip you ever notice on the window pane in autumn a
dead, swollen fly sticking to the glass by its tongue -and
feet, with a circle of white, powdery dots about it resem-
bling a halo, and with an abdomen so swollen that it
seems to be made up of alternating black and white rings?
If you break the fly apart, you will probably find it brittle,
and with a lens you can see whitish threads inside.

‘This fly is the victim of a parasitic fungus somewhat
similar to many of the fungi that cause disease and death
in the higher plants. The white dots are the spores of
the fungus thrown out from the fruiting threads that have
developed in the body. By means of these spores other
living flies may catch the disease and die.

One who understands how dangerous flies are as carriers
of the germs of typhoid fever and other diseases of man-
‘kind will not regret that they themselves are thus destroyed
by this parasitic fungus. Consequently it is easy to ac-
knowledge that we have friends as well as foes in the great
group of fungi.

The halo-producing fly parasite is a typical example of
the family of Insect-killing Fungi (Entomophthoree). It
belongs to the genus Empusa, so called because the Greeks
in ancient times used the name Empusa when they fancied
they saw “‘a weird specter of constantly changing shape.”

A parasitic fungus closely related to that which attacks
the house fly often occurs in colonies of aphides or plant

271

272 FARM FRIENDS AND FARM FOES

lice. During moist weather, which is especially favorable
to the growth of fungous diseases of insects, this aphid
parasite often destroys billions of victims, checking destruc-
tive outbreaks of crop pests. You can readily distinguish
with a lens the plant lice that are killed by the fungus from
those killed by insect parasites.

A similar fungus is often very helpful in checking out-
breaks of the chinch bug, and has been the subject of
many investigations to determine whether it can be utilized
as a remedy for this insect. .Dead bugs covered with the
whitish, moldlike growth of the fungus may generally
be found wherever chinch bugs are abundant. While
probably the artificial propagation and dissemination of
the bugs hastens the spread of the malady, the success of
the measure is largely dependent upon the damp weather
favorable to the development of the disease.

Fortunately these insect-killing fungi attack caterpillars
of many kinds. A short search among cabbages will often
show a cabbage worm killed by such a disease. The body
of the caterpillar is filled with the fungous threads which
convert it into a mummified condition, and finally produce
upon the surface a crop of spores. Many other insects, es-
pecially grasshoppers, are attacked by a similar disease.

CATERPILLAR Funai (Ascomycetes)

Another group of these insect parasites attacks caterpil-
lars of many kinds, and are often called the Caterpillar
Fungi. They belong to the great group of Ascospore
Fungi to which so many diseases of plants belong. They
are readily distinguished by the strange, clublike projection
in which the ascospores are developed. Two of these
mushroom-like bodies coming from a fly are shown in the
picture on the next page. White grubs are often killed

FUNGOUS DISEASES OF INSECTS 273

by a fungus belonging to this group, developing a curious
growth that generally projects from the head.

WHITE Fry Func

One of the most noted illustrations of the effect of para-
sitic fungi upon injurious insects is found in the case of
the White Fly or Aleyrodes, various species of which are
destructive to orange and other trees in the Southern and
Pacific coast states. Similar species are also
destructive in greenhouses in the North.
At least seven distinct forms of the fungi are
known to attack these insects, and many
successful experiments have been made in Le
spreading the diseases artificially. The most FLY witx
effective way is by washing into water the. — a
- spores that have developed on the insects killed by dis-
ease, and spraying the water on the infested plants. Thé
Florida Experiment Station has shown that this method is
_ easy and effective. The spraying apparatus must have no
copper in it, except the nozzle, as faint traces of copper are
liable to kill the spores. Another method is simply to pin
leaves covered with the dead insects upon the branches of
trees that are infested by White Flies. The disease-
producing fungi are most likely to spread during wet
weather.

BACTERIAL DISEASES

‘The diseases of insects due to Bacteria are perhaps
more important than any others. When tent caterpillars,
cutworms, army worms, or various other insects become ex-
tremely abundant, they often die suddenly in great num-
bers, seeming to be affected by a sort of cholera that causes
death and rapid decay. This is a bacterial disease.

274 FARM FRIENDS AND FARM FOES

Not all bacterial diseases of insects, however, are
helpful to man. The Foul Brood, which is so destructive
to honey-bees, and the dreaded flacherie of silkworms, are
both due to these microscopic germs. They cause great
losses to the bee-raising and silk industries.

OBSERVATIONS FOR PUPILS

I. Inautumn look for flies that show the ring of spores around them.

2. Look for diseased aphides or plant lice, especially between cab-
bage leaves and on clover plants. ,

3. Keep watch for dead grasshoppers clinging to the tops of
wire fences or herbaceous plants.

4. If you live in a region where chinch bugs are found, hunt for
dead, moldy specimens.

5. If you-live in a region where white flies are abundant, look
for those killed by fungus, and try spreading the disease.

6. When you find any of these diseased: insects, place them in a
‘glass, add a few drops of water, and cover tightly. Watch daily for the
development of spores. Examine these under the microscope.

7. Read this reference : — Nature Biographies, pages 89-95,

BACTERIA; HIGHLY MAGNIFIED

CHAPTER XXVI

Bacteria and Plant Food

Ir has been shown in an earlier chapter that the micro-
scopic forms of life called microbes or bacteria often cause
serious losses on account of the blights and rots that they
induce in plants. Such bacteria are true parasztes, develop-
ing within the tissues of living plants and causing injury
and death. It is well known that vast numbers of bacteria
are similarly parasitic upon animal life, causing many of
the most fatal diseases in man and the lower animals.
Most of these forms of germ life must, of course, be
reckoned among the farmer’s foes.

THe NITRIFYING BACTERIA

There are many other bacteria, however, that may well
claim to be friendly to the farmer, for they serve an im-
portant purpose in furnishing food to his crops. One
group of these is present in vast numbers in fertile soils
where they help to form the xdtrates which are very im-
portant in supplying food to plants. The plant or animal
materials added to the soil for fertilizing purposes con-
tain nitrogen in combination with various other elements.
Consequently most of the nitrogen in the soil exists in the
form of these organic compounds—that is, compounds
made by organized or living things. In order that the
‘nitrogen in these organic compounds may be utilized by
growing plants, it must be recombined to form ztrates —

275

276 FARM FRIENDS AND FARM FOES

that is, combinations of nitrogen, oxygen, and some element
like lime or potash — which are readily absorbed through
the roots of plants.

There are certain sorts of bacteria the special function
of which is to convert the organic nitrogen into nitrates.
These are called the Mitrifying Bacteria. During this
process the organic material is first converted into an am-
monia form, then into a nitrite form, and finally into the
nitrate form. In a general way this isa change from a
condition in which the nitrogen is insoluble into a condition
in which it is readily dissolved.

During recent years the importance of this nitrifying
process has received a great deal of attention. It is now
recognized that good farming involves such treatment of
the soil that these friendly germs may do as much work as
possible, and that their abundance is an important test of
soil fertility.

THE NITROGEN-GATHERING BACTERIA

In addition to the store of nitrogen in the soil which is
unavailable until it is changed into the nitrate form by the
nitrifying bacteria, there is an even greater store of it in
the air. This supply is so great that it has been estimated
that there are seventy-five million pounds of nitrogen rest-
ing upon every acre of land. This nitrogen in the air,
however, cannot be used directly by plants, so that it
seems to have little value as a fertilizer.

But here again the friendly germs come to the farmer’s
help. If you dig up a vigorous red clover plant and wash
the soil carefully away from its roots, you will probably find
upon the latter many small, roundish tubercles. If you treat
a soy bean plant in the same way, you will find a condition
like that pictured on the opposite page... And you may easily

BACTERIA AND PLANT FOOD 277

find similar tubercles upon the roots of beans, peas, vetches,
sweet clover, alfalfa, and various other members of the great
family of legumes, or pod bearers.

It took a long while for man to trace the connection
bétween these tubercles upon the roots of the pod-bearing
plants and the free nitrogen of the air. There is still much
mystery about it, but we now know that the tubercles or
nodules are composed chiefly of _
colonies of bacteria, andthatthese _
bacteria are able to convert the
free nitrogen in the air between |
the soil particles into a form that
is utilized by the plants. They
may well be called the WVztrogen-
gathering Bacteria, and are to be
classed among the farmer’s best
friends.

We have seen that some bac-
teria may live as parasites upon
living plants or animals: these are
the Parasitic Bacteria. We have
also seen that some bacteria —
including the nitrifying forms —
may liveassaprophytes upon dead
and decaying plants or animals: these are the Saprophytic
Bacteria. We have now to determine the relation of the
nitrogen-gathering bacteria to the leguminous plants. Evi-
dently they are not parasites, for they help rather than in-
jure the growth of the plant. Nor are they saprophytes,
for they develop upon living rather than dead plants. They
seem to form a sort of partnership with the plants. They
need a home to grow in and some help to get their growth;
in return they gather nitrogen for the benefit of their hosts.

ROOT OF Soy BEAN SHOW-
ING TUBERCLES

278 FARM FRIENDS AND FARM FOES

When we speak of two plants thus living together in mutual
helpfulness, we use the word symdioszs : so we say that the
nitrogen-gathering germs are Symbzotic Bacteria.

These symbiotic bacteria are of great importance to prac-
tical agriculture. In most good systems of crop rotation,
clover or some other leguminous plant is grown every few
years in order that the supply of available nitrogen in the
soil may be increased. Clover is able to increase this supply
because of the help given by the germs living in the nod-
ules on the clover roots. One of the best ways to improve
poor soil is to grow a leguminous crop and plow it under
as green manure. The value of this process lies largely
in the presence of the nitrogen-gathering bacteria. When
an alfalfa field is well established, it may be left undisturbed
except for harvesting the crops, for many years. Presum-
ably it is able thus to yield its forage year after year be-
cause the bacteria in the nodules on the roots are gathering
free nitrogen from the air.

A striking example of the effectiveness of these bacteria
in gathering nitrogen has been recorded by the Illinois Ex-
periment Station. Three sets of ten cowpea plants with
tubercles on the roots were analyzed to determine the per-
centage of nitrogen. Three othersets of ten cowpea plants
without tubercles were also analyzed for comparison. ‘The
infected plants contained nearly four times as much nitrogen
as the plants not infected, and about three fourths of the
total nitrogen in the infected plants was obtained from the
air. The roots and tubercles of the infected plants con-
tained six to seven times as much nitrogen as the roots of
the plants not infected.”

It is an interesting fact that the bacteria found in nodules
on the roots of red clover will not develop upon the roots
of cowpeas or several other related plants. Similarly, the

BACTERIA AND PLANT FOOD 279

- bacteria from cowpeas will not develop upon red clover.
Thus in a broad way we may say that each distinct legumi-

AE

RED CLOVER: EFFECT OF -BACTERIA

nous crop has a special form of symbiotic microbe and that,
as a rule, these microbes are not interchangeable.

DeEcay oF NODULES

Another important fact is that most of these bacteria
are unable to live independently in the soil more than five
or six years after the crop on which they develop has
disappeared. Consequently we cannot expect to find in a
given soil the various germs waiting to develop upon any
leguminous crop that may be planted. Nor in most cases
is it safe to assume that enough of these germs will adhere

280 FARM FRIENDS AND FARM FOES

to the seed and be planted with them to insure a good de-
velopment of tubercles upon the roots.

Consequently, the conditions that exist in a given case
may be something like this: Here is a field in which no
red clover has been grown in a dozen years. The soil is
poor and sour. It produces very small crops and evi-
dently needs to be improved. We wish to grow red clover
to help its condition. Evidently we must get rid of the
sourness by a liberal application of lime or some other
alkaline fertilizer. Then we must introduce the clover
tubercle germs into the soil and .sow the seed. Such intro-
duction of germs is often spoken of as zmoculation — that
is, we inoculate the soil with the desired microbes in the
expectation that when introduced they will thrive and
multiply upon the clover roots. One of the simplest ways
of inoculating is to bring a quantity of soil from a field in
which clover has been growing successfully. Being sure
that the plants grown in the soil have shown plenty of
nodules, spread it broadcast and harrow it in. We may
thus get a very general dispersal of the germs where they
will come in contact with the developing clover roots.

Another way to inoculate the soil is to shake up in a
bottle of water a small quantity of soil from a thriving
clover field. Let it stand until the soil particles settle, and
pour the clear liquid over the clover seed or upon the soil
where the seed is planted. This method is especially use-
ful in pot experiments.

Fortunately, these nitrogen-gathering bacteria can be
induced to develop in vast numbers in what are called
nutrient solutions. The scientists of the United States
Department of Agriculture have been at work for many
years upon the methods of growing bacteria in such solu-
tions. They have succeeded so well that the Department

BACTERIA AND PLANT FOOD 281

now offers to the public small culture tubes of the microbes
of each of the important leguminous crops, with precise
directions for their use. This enables any one to inoculate
his soil for any crop desired.

Experience has shown that with some crops at least it is
worth while at first to grow the same crop for two suc-
cessive seasons in order to secure a thorough inoculation of
the soil. After that, if the crop is grown in rotation every
four or five years, the microbes are likely to continue
present in such numbers that further inoculation is un-
necessary.

The germs that grow upon cowpeas seem very generally
present in the soil of the Southern states. Consequently
it is seldom necessary to inoculate for this crop.

The germs that grow upon sweet clover or melilot seem,
to be able to develop with equal vigor upon alfalfa. Con-
sequently, it is often practicable to inoculate alfalfa fields
with soil in which sweet clover has been growing.

OBSERVATIONS FOR PUPILS

1. Make a list of the leguminous plants in your locality upon which
you find root tubercles.

2. Compare the abundance of the tubercles with the vigor of the
plant.

3. Grow red clover in sand or other soil deficient in nitrogen, being
sure it is from a field where red clover has not grown. Apply the
germs obtained as suggested on page 280, to part of the pots, but not to
all. See which set grows best, making sketches every two weeks.

4. Read such of these references as your teacher directs :—

Leguminous Crops for Green Manuring, Farmers’ Bulletin 278. Progress in
Legume Inoculation, Farmers’ Bulletin 315. The Renovation of Worn-out Soils,
Farmers’ Bulletin 245. Alfalfa, Farmers’ Bulletin 339. Clover Farming on the
Sandy Jack-pine Lands of the North, Farmers’ Bulletin 323. Canadian Field
Peas, Farmers’ Bulletin 224. Cowpeas, Farmers’ Bulletin 318. The Liming of
Soils, Farmers’ Bulletin 77.

PART IV

FRIENDS AND FOES AMONG THE
BIRDS

A PAGE FROM A BIRD BOOKLET

THE BOOKLET ON BIRDS

Birds are more difficult to draw than plants or insects. Consequently
this booklet is likely to have fewer pages of drawings of the birds themselves,
though these may readily be replaced by drawings of fruits, seeds, and insects
which are eaten by birds, as well as by mounted pictures cut from magazines,

Abundant opportunities for written or printed pages may be found in the
suggestions at the ends of the chapters on birds. Delightful poems con-
cerning birds are readily found and may be copied for the booklet,

CHAPTER XXVII

The Relations of Birds to Fruit Orchards

In a large part of North America the apple is the lead-
ing orchard fruit. The pear and the peach are much less
generally grown, although each is important in certain
localities. The same is true of cherries, plums, and quinces,
though in the aggregate each of these fruits is of great
value. :

These orchard trees are subject to attack by a great variety
of insect enemies. Root, trunk, branch, twig, leaf, and
fruit — each part has special enemies that too often blight
the crop. Fortunately, however, most of these enemies are
largely held in check by various birds that frequent the
orchards and help to keep a balance that is favorable to
fruit production. Where birds are scarce the task of fruit-
raising is greatly increased.

Trunk, Roots, AND BRANCHES

The trunk and the larger roots and branches of most
fruit trees are subject to attack by a great variety of burrow-
ing insects. In general, the eggs are laid on or in the bark
by a winged beetle or moth. These eggs hatch into larve
that burrow in bark, sapwood, or heartwood, remaining at
work until full grown aslarve. They then change to pupe,
generally in or near the outer bark, and emerge later as
adult beetles or moths. ,

Common examples of such destructive insects are found
in the round-headed apple-tree borer, the flat-headed borer,

285

286 FARM FRIENDS AND FARM FOES

the peach-tree borer, the fruit-bark beetle, and the sinuate
pear borer.

Set over against these enemies of trunk and branch, we
find the woodpeckers, nuthatches, creepers, and chickadees.
These birds are constantly searching the bark for the larvae
and pupz concealed within, and they are wonderfully adapted
both to discover the position of the pests and to dig them
out. The long, barbed tongue of the woodpecker can be °
thrust into the hole made by a borer and draw the larva
quickly forth. The larger and more deeply embedded
larve are especially sought by the woodpeckers, while the
smaller insects on or near the surface are eaten by the
nuthatches, creepers, and chickadees.

The twigs or smaller branches of fruit trees are attacked
by a great variety of insect enemies. The sap is sucked
through the bark by hosts of scale insects or bark lice, and
aphides or plant lice, as well as by tree hoppers and related
pests. Many of the birds already mentioned feed freely
upon these various insects, the nuthatches, creepers, and
chickadees being especially useful in this respect. These
are not alone, however, in the good work. They are
assisted by the orioles, sparrows, vireos, warblers, gros-
beaks, wrens, gnat catchers, bluebirds, and other feathered
friends. Inthe case of the scale insects alone, fifty-seven
kinds of birds have been listed as feeding on them.

Bups AND LEAVES

When we consider the relations of birds to the enemies
of the buds and leaves of orchard trees, we find so close a
connection that we are forced to conclude that the life of
the trees depends upon the birds. Tree leaves are beset by
a bewildering host of insect enemies. Aphides, scale in-

RELATIONS OF BIRDS TO ORCHARDS 287

sects, leaf hoppers, and many other true bugs suck out the
sap; leaf miners of many sorts mine the leaves; while
beetles, grasshoppers, crickets, and numberless caterpillars
devour the blades.

Set over against these myriads of leaf-feeding insects,
we find the great majority. of our familiar birds. Watch
the birds in an orchard on a summer day and you will be
convinced of their great value
as insect destroyers. If you
are keen-eyed and patient,
you will see the warblers and
other smaller birds searching
leaf after leaf for aphides and
tiny caterpillars, while vireos,
bluebirds, robins, thrushes,.
sparrows, cedar birds, cuckoos,
_catbirds, blackbirds, and others
are devouring the larger en-
emies. If you watch these
birds at their nests, you will
see that the young are fed
with vast numbers of such
insect foes. Even in winter ara Wee
the eggs and pupe are con- TACKED BY BIRDS
tinually eaten by birds.

The enemies of the fruits of orchard trees are less
numerous than those of the leaves, but still their name is
legion. Scale insects, beetles, bugs, caterpillars, maggots,
midges, and other pests all attack one kind of fruit or
another, often destroying the bulk of the crop. The birds
that attack these enemies are nearly as numerous as those
that attack leaf-feeding insects, and the good they do is
incalculable.

288 FARM FRIENDS AND FARM FOES

What is true of the relations between insects and birds
in orchards of deciduous fruits is equally true in orchards
of citrous fruits. Wherever oranges, lemons, and related
trees are grown for profit, hosts of insect enemies attack the
trees. These insects are preyed upon by birds which help
greatly in checking the injuries of the pests.

AERIAL INSECTS

Nearly all the insects that affect orchards exist part of
their lives in a winged condition in which they fly through
the air from branch to branch or from tree to tree. At
such times they are in danger of being snapped up by
flycatchers, vireos, swallows, and other birds. Most of
these keep watch over comparatively limited spaces near
the trees, but the whole realm of the air is patrolled
by the swallows. Over the water or above the land the
flying insect is in danger of being suddenly captured in the
swallow’s beak. The food of swallows consists chiefly of
insects thus caught upon the wing; beetles, flies, ants, and
small moths are all taken in great numbers. Consequently,
these birds are as useful as they are beautiful, and should
be encouraged by every one.

At night, also, the war against flying insects is kept up
by the whippoorwills and nighthawks. These interesting
birds patrol the air in dusk and darkness, catching flying
insects of many kinds in their capacious jaws.

OTHER ENEMIES

There are other enemies of orchard trees besides the in-
sects. The trunks are frequently girdled by meadow mice
and-rabbits that gnaw the bark. This generally happens
in winter, when the mice work beneath the surface of the

RELATIONS OF BIRDS TO ORCHARDS 289

snow. Fortunately, however, hawks, owls, and other large
birds feed freely upon these pests and commonly keep
their numbers so reduced that little damage is done. But
in regions where the hawks and owls are ruthlessly perse-
cuted, the mice and other rodents become destructive, and
often cause the loss of valuable trees.

It would perhaps be too much to expect that birds
should do no harm in orchards to offset the immense good
they do. In certain ways they doubtless cause damage,
but this is on the whole vastly less than the benefit they
confer. Some birds eat fruit, especially cherries, to a
serious extent. It is indeed probably true that in fruit-
growing regions there are often more robins than are
beneficial to horticulture.

Birds also cause the spread of scale insects and probably
of fungous diseases, although little real injury is done in
these ways. At least one bird —the true sapsucker —
.sometimes injures the trees by boring holes in the bark
and taking the sap, though this should not lead to the
killing of the beneficial woodpeckers, which the sapsucker
resembles.

The chief damage done to fruit by birds generally
results from the extraordinary abundance of one kind of:
bird. Thus, in the eastern region of the United States the
robin is often troublesome because it occurs in great num-
bers and attacks cherries and small fruits. On the Pacific
coast it is sometimes very destructive in olive orchards.
In the latter region birds are more injurious to fruit than
in the East, partly because of the scarcity of wild fruits.
The house-finch or linnet, the Brewer blackbird, the black-
headed grosbeak, and the California jay often become
serious pests, although each of these doubtless does con-
siderable good in other ways.

290 FARM FRIENDS AND FARM FOES

OBSERVATIONS FOR PUPILS

BirDs IN APPLE ORCHARDS

A

1. Make a list of the birds you have seen searching the bark of the
trunk and larger branches of apple trees.

2. What birds occur on apple trees in winter?

3. What birds have the habit of snapping up insects in the air?

4. Make a list of all the different birds that you can find in apple

orchards.
B

1. Write a little story with this title : The Birds in Our Orchard.
Simply tell what you have seen.
2. Read as many of these references as you have access to: —

Birds in their Relation to Man, pages 1-8, 68-80, 304-315. Useful Birds and
their Protection, pages 149-154. How Birds Affect the Orchard, Yearbook Reprint
197. Does it Pay the Farmer to Protect the Birds ? Yearbook Reprint 443. The

- Relations between Birds and Insects, Yearbook Reprint 486.

CHAPTER XXVIII

The Relations of Birds to Meadows and Pastures

WHILE the insects that affect the grasses of meadow
and pasture lands are by no means: so numerous as in the
case of the orchards, there are enough to prove seriously
destructive at times. If this is true with the constant
check the birds keep upon them, there is little doubt that
they would do vastly greater damage were there no birds.

The various forms of locusts or grasshoppers with short
antennz are among the most abundant of meadow and
pasture pests. They are nearly always present in sufficient
numbers to do some damage, and often become so abundant
as to destroy the growing crop. The meadow grasshoppérs
with long antenne are often abundant enough to do some
injury. The much smaller leaf hoppers are also nearly al-
ways present and do much more damage than is generally
supposed. Many sorts of cutworms, including the notorious
army worm, are always feeding on the blades of grass near
the ground, and other kinds of caterpillars
are continually at work.

In addition to these enemies of the stems
and blades, the roots of grasses are attacked
by many pests. The voracious white grubs
—the larve of the familiar May beetles; the {-
slender yellow wireworms — the larve of the
common click beetles; the curious meadow
maggots—the larve of the long-legged crane flies, —these
and many other pests feed upon the roots of grasses.

291

MAY BEETLE

292 FARM FRIENDS AND FARM FOES

The clovers and other forage crops often grown in mead-
ows have their special insect enemies that furnish food for
many birds.

The variety of bird life that is found in grasslands is
also much smaller than in the case of orchards. Compar-
atively few species have adapted themselves to live upon
the ground in grasses, but these few
are of immense benefit as destroyers
of insect pests.

The most notable meadow and
pasture birds are these: the meadow
lark, the crow, the various black-
birds, the bobolink, the cowbirds,
the ground sparrows, and the robin.
While these do not all live exclusively on the ground in
grasslands, they find there an important part of their yearly
food supply.

The Meadow Lark isa typical example of these birds. It
is an abundant and widely distributed species, living habit-
ually in grasslands and finding there practically all its food.
Originally a native of the great prairie regions, it has grad-
ually spread as forests have been replaced by fields and
meadows until it is now found over practically the whole
of the United States.

The food of the Meadow Lark has been carefully studied
by many competent .investigators. In Illinois Professor
Forbes found that at least three quarters of the food during
the spring and summer consisted of insects. Cutworms,
army worms, and other caterpillars formed more than a
quarter of the food supply, while various beetles formed a
fifth and grasshoppers more than an eighth. The beetles
eaten included June beetles, blister beetles, curculios,
click beetles, and plant beetles. Twenty chinch bugs

CLICK BEEILES

.

RELATIONS OF BIRDS TO MEADOWS 203

had been eaten by one bird, and others had devoured
crane flies.

Studies in other places show similar results and bring
out the fact that in autumn when insects become more
scarce the Meadow Lark feeds freely upon the seeds of
weedy plants. It consequently is of great value wherever
it is found, and should be given the most careful protection.

The Bobolink 1s one of the most delightful of meadow
birds. It is also one of the most useful, for it feeds freely
on grasshoppers, caterpillars, and
other insect pests as well as on the
seeds of weedy plants. In the
North it is eminently beneficial,
though on its way southward it
often becomes a pest in rice fields.

While it cannot fairly be claimed
that the Crow and the various
Blackbirds are entirely beneficial, there is no doubt that
they do much good to offset some harm. So far as their
actions concern meadows and pastures, these birds are of
benefit, for they devour vast numbers of grasshoppers,
cutworms, army worms, white grubs, June beetles, and
other pests. The harm they do is chiefly in grain fields,
either at the time of planting or that of harvesting.

There are several kinds of Sparrows that live more or
less on the ground in pastures and meadows. The more
important are these: the Field Sparrow, Song Sparrow,
Vesper Sparrow, Savanna Sparrow, and the Dickcissel.
All of these birds feed freely upon grass insects, destroying
vast numbers of crickets, grasshoppers, cutworms, and other
caterpillars, as well as the seeds of weedy plants. The
young are also fed with similar insects, so that these birds
are eminently beneficial.

MEADOW GRASSHOPPER

204. FARM FRIENDS AND FARM FOES

The presence of flocks of Robins searching grasslands
for food is one of the characteristic sights of early spring.
At no other season, perhaps, do these birds search so
persistently upon the ground. A large proportion of the
grasshoppers, cutworms, army worms, and other grass
insects that have succeeded in living through the winter
are then eaten by the
Robins. This early
spring destruction of
such pests is of great
-value in checking their
increase, and the birds
atone for many sins in
the cherry trees by
their actions at this
season.

No consideration of
the relations of birds
to insects of grass-
Jands would be ade-
; quate that did not

SCREECH OWL take account of the

flycatchers, swallows,

swifts, whippoorwills, and nighthawks, a large part of

whose food consists of grasshoppers, leaf hoppers, beetles,
moths, and other pests of grasslands.

As their name indicates, the meadow mice are often very
destructive in pastures and meadows. They destroy much
grass by feeding upon crowns or roots, and their runways
in spring often show how busy they have been beneath
the snow in winter. The hawks and owls are the most
important natural checks upon these pests. The experi-
ences of many regions show that where these birds are

RELATIONS OF BIRDS TO MEADOWS 295

relentlessly persecuted, the meadow mice are likely soon
to multiply to an alarming extent, sometimes destroying the
crops in whole fields.

OBSERVATIONS FOR PUPILS

BIRDS IN MEADOWS AND PASTURES

1. Make a list of the most important grass-feeding insects in your
locality.

2. Make a list of the birds you have seen upon the ground in pas-
tures or meadows, or both.

3. Make a list of the birds that build their nests on the ground in
pastures and meadows.

4. Read as many of the following references as are accessible : —

Farmers’ Bulletin 54, pages 15-28. The Bird Book, pages 248-253. Birds in
their Relations to Man, pages 137-144, 158-171. Useful Birds and their Protection,

pages 76-80, 310-333.

CHAPTER XXIX

The Relations of Birds-to Gardens and Fields

THE conditions in regard to the crops and insects of
gardens and cultivated fields vary in different regions.
Consequently, it seems best to indicate the relations of
birds to them by considering a few of the more widely
distributed species that live chiefly in such situations.

SPARROWS

The little Chipping Sparrow is one of the most abun-
dant of the smaller birds found in gardens and fields near
houses. Inthe North it arrives early in spring and remains
till late in autumn. Its food consists of insects and the
seeds of grasses and weeds. Nearly half of the food often
consists of the seeds of such noxious plants as pigeon
grass and crab grass. Cutworms, cankerworms, bugs,
moths, ants, beetles, and grasshoppers are among the
insects eaten by both young and adults. In consequence
of such feeding habits, this familiar little bird is very use-
ful and should be encouraged in every way possible.

On account of its attractive voice the Song Sparrow is
perhaps an even greater favorite than the Chipping Spar-
row. It is found everywhere in fields and gardens, keep-
ing close to the ground where insects and weed seeds are
abundant. It remains through the winter as far north as
Massachusetts.

The other native ground-loving sparrows —such as the
Field Sparrow, the Savanna Sparrow, the Vesper Sparrow,

296

RELATIONS OF BIRDS TO GARDENS 297

and the Junco—have similar feeding habits. They are
especially useful as destroyers of the seeds of weeds. In
this respect, however, they are probably surpassed by the
related sparrows that do not live so much upon the ground.
These include the Tree Sparrow, the Goldfinch, the White-
crowned Sparrow, the White-throated Sparrow, and the
Snowflake. These are preéminently seed eaters, and they
undoubtedly destroy thousands of tons of weed seeds every
year.

The bird commonly known as the English Sparrow
was brought into America from Europe in 1850 and again
three years later. These birds were imported because it
was thought that they would assist in the suppression of
the cankerworm, an insect very destructive to the leaves
of shade trees. After their introduction they thrived and
spread rapidly, being carried by man from city to city so
that before many years they were very generally distrib-
uted.

English sparrows are by preference city birds; they utilize
all sorts of crevices about buildings for nesting and roost-
ing purposes, and live upon a great variety of food. From
towns they gradually disperse through the surrounding
country, congregating about farm buildings. They breed
rapidly, and have few enemies. When well fed, they can
stand very cold weather without injury.

As a destroyer of noxious insects, this sparrow has been
generally, though not always, a failure. There are also
many misdemeanors charged to him. It is known that he
habitually destroys the buds and blossoms of trees, and at-
tacks ripening fruit of many kinds, as well as peas on the
vines and seeds in the soil. Grains in the field are also
devoured by the sparrows; houses are made filthy by their
presence; and native birds are driven away by them.

298 FARM FRIENDS AND FARM FOES

With these and other charges the sparrows stand indicted ;
and they have comparatively little good to counterbalance
the evil. Consequently, it would seem that they should
not be encouraged near farm buildings.

BLuEBIRDS, ROBINS, AND CATBIRDS

Next to the sparrow, the Bluebird is one of the most
abundant species found in gardens and cultivated fields.
Fortunately, this universal favorite is as useful as it is beau-
tiful. Its food has been most carefully studied by Profes-
sor S. A. Forbes, who writes : “ One hundred bluebirds at
thirty insects each a day would eat in eight months about
730,000 insects. If this number of birds’were destroyed,
the result would be the preservation on the area supervised
by them of about 70,000 moths and caterpillars (many of
them cutworms), 12,000 leaf hoppers, 10,000 curculios, and
65,000 crickets, locusts, and grasshoppers. How this
frightful horde of marauders would busy itself if left. un-
molested no one can doubt. It would eat grass and clover
and corn and cabbage, inflicting an immense injury itself
and leaving a progeny that would multiply that injury
indefinitely.”

The Robin is very useful in destroying insects that live
on or in the ground. It feeds freely upon such pests as
cutworms, white grubs, and grasshoppers. It is especially
busy in meadows when it first arrives in early spring.

The food of the Robin as determined by the investiga-
tions of the United States Department of Agriculture has
been summarized as follows: “ An examination of 300
stomachs shows that over 42 per cent of its food is animal
matter, principally insects, while the remaiaser is made
up largely of small fruits or berries. Over- 19 per cent

RELATIONS OF BIRDS TO GARDENS 299

consists of beetles, about one third of which are useful
ground beetles, taken mostly in spring and fall when other
insects are scarce. Grasshoppers make up about one
tenth of the whole food, but in August comprise over 30
per cent. Caterpillars form about 6 per cent, while the
rest of the animal food, about 7 per cent, is made up of
various insects, with a few spiders, snails, and angle
worms. All the grasshoppers, caterpillars, and bugs, with
a large part of the beetles, are injurious, and it is safe to
say that noxious insects comprise more than one third of
the robin’s food. Vegetable food forms nearly 58 per cent
of the stomach contents, over 47 being wild fruits, and only
a little more than 4 per cent being possibly cultivated va-
rieties. Cultivated fruit amounting to about 25 per cent
was found in the stomachs in June and July, but only a
trifle in August. Wild fruit, on the contrary, is eaten in
every month, and constitutes a staple food during half the
year. No less than 41 species were identified in the
stomachs; of these, the most important were four species
of dogwood, three of wild cherries, three of wild grapes,
four. of greenbrier, two of holly, two of elder; and cran-
berries, huckleberries, blueberries, barberries, service ber-
ries, hackberries, and persimmons, with four species of
sumac, and various seeds not strictly fruit.”

There is no doubt that the Robin is a very useful bird,
when we consider its life through the year. But it is also
true that at times, especially in fruit-growing regions, it is
decidedly injurious.

No country boy needs to be introduced to the Catbird.
It is familiar to every one who has wandered along a
roadside or by the margin of woods. It is a useful bird,
although it sdmetimes helps itself too freely to the fruits
of the orchaid and garden. “Ants, beetles, caterpillars,

300 FARM FRIENDS AND FARM FOES.

and grasshoppers constitute three fourths of the animal
food,” writes Professor Beal, “the remainder being made
up of bugs, miscellaneous insects, and spiders. One
third of the vegetable food consists of cultivated fruits
or those which may be cultivated, such as strawberries,
raspberries, and blackberries; but while we debit the bird
with the whole of this, it is probable — and in the eastern
and well-wooded part of the country almost certain — that
a large part was obtained from wild vines. The rest of
the vegetable matter is mostly wild fruit, such as cherries,
greenbrier, spice berries, black alder, sumac, and poison
ivy.” About half of the food of the Catbird is of animal
and half of vegetable nature. Planting wild fruits in out-
of-the-way corners is recommended to keep these birds
away from the fruit garden.

BLACKBIRDS AND CROWS

‘ Two kinds of Blackbirds are generally to be found in the
Northern states. The larger of these is the Crow Black-
bird, of which there are two forms — the Bronzed Grackle and
the Purple Grackle, large and handsome birds, familiar to
country boys throughout their range. Their food consists
of insects, grains, and other vegetable matter, insects
forming about one third of the total. These birds are
frequently destructive to ripening wheat or other grain
crops, and no doubt often do as much harm as good. But
in general they should not be molested except when
causing damage.

The Redwinged Blackbird is smaller than the Grackles,
although in regions favorable for its breeding it is likely to
be much more abundant. It builds its nest in low bushes
on the borders of swamps; and in the West often appears

RELATIONS OF BIRDS TO GARDENS 301

in enormous flocks in grain fields,doing much damage.
But its injuries are partly atoned for by the fact that it eats
large numbers of injurious insects, many of them being
grain-destroying pests.

In the Pacific coast region the Brewer Blackbird is
abundant. Its friends have to confess that it is fond of
cherries, but they also claim that it is a great destroyer
of insects. When Professor F. E. L. Beal was studying
these birds as they were eating fruit in a California cherry
orchard, a neighboring fruit grower began plowing. “ Al-
most immediately every blackbird in the vicinity was upon
the newly opened ground, and many followed within a few
feet of the plowman’s heels in their eagerness to get every
grub or other insect turned out by the plow.”

There is a great difference of opinion about the economic
relations of the common crow—a bird that is abundant
over most of the United States. Many people accuse it,
and with justice, of pulling up sprouting corn, robbing
birds’ nests, and carrying off young chickens as well as of
eating small wild animals—such as toads, frogs, and
snakes — which are beneficial to man. To counterbalance
these sins, however, it is certain that the crow destroys
large numbers of noxious insects. It also feeds freely
upon various wild berries and fruits, including the sumac,
dogwood, sour gum, and poison ivy.

The chief injury to corn is done by the birds pulling up
the young plants or feeding upon the swollen kernels after
they become softened by the moisture of the soil.

FLYCATCHERS, SWIFTS, AND SWALLOWS

A distinct phase of the war against insect pests is-car-
ried on by Flycatchers such as the Phoebe and the King-

302 FARM FRIENDS AND FARM FOES

bird. These perch upon fences, trees, tall weeds, or posts
wherever they can watch the surrounding air space.
When a fly, moth, beetle or other insect comes near, the
bird sallies forth and snaps it in its beak. In this way
they get nearly all their food.

‘In the case of the Phoebe more than nine tenths of the
food consists of insects and spiders, chiefly those caught
in the air. In the case of the Kingbird the proportion is
almost as great. To a less extent the Bluebird and the
Cedar Bird have similar fly-catching habits.

The greater spaces of the air over gardens and culti-
vated fields are patrolled during the day by the Swifts and
Swallows and during the night by the Whippoorwills and
Nighthawks. All of these spend hours upon the wing,
continually catching the myriads of winged insects that fly
from place to place. The service thus rendered is of in-
calculable value, and every one should strive to protect
these feathered friends from enemies of every sort.

It is commonly believed that the Hawks and Owls are
enemies of the farmer, to be destroyed whenever possible.
But the careful studies and observations of many com-
petent observers show that a majority of these birds are
friends whose presence we could scarcely afford to lose.
They destroy great numbers of mice and insects, and in
Europe are recognized as beneficial birds.

The Marsh Hawk is one of the most useful birds of
prey, and deserves man’s protection. “Its food,” writes
Dr. A. K. Fisher, “consists largely of small rodents, such
as meadow mice, half-grown squirrels, rabbits, and ground
squirrels.” The stomach of a New Hampshire specimen
that I examined was full of grasshoppers.

The Sparrow Hawk is a small species that feeds almost °
wholly upon insects, chiefly grasshoppers, when these can

RELATIONS OF BIRDS TO GARDENS 303

be obtained. In the sparse pine woods of southern Florida
I have found the Sparrow Hawk one of the commonest
winter birds. One of its favorite methods of obtaining
food there is to perch in trees’on the outskirts of the forest
fires that frequently occur, and catch the grasshoppers,
lizards, and other animals driven from cover by the flames.

OBSERVATIONS FOR PUPILS

BIRDS IN GARDENS AND FIELDS
A

1. Write a short account of birds that you have found in the yard
and garden about your house. Tell what kinds you have seen and
what you have observed them eating.

2. If the English Sparrow is found near your home, write a special
essay about it. Tell whether it drives away other birds, what it feeds
upon, where the nest is made, and how many broods there are each
season.

B

1. Write a short essay with this title: My Favorite Bird.

2. Illustrate your booklet with such drawings as you can make,
and if you have bird pictures in magazines or papers that can be cut
out, paste them in also.

3. Look up the discussions of the field and garden birds you are
most interested in as found in these references : —

The English Sparrow, Farmers’ Bulletin 383. The Meadow Lark and Balti-

more Oriole, Yearbook Reprint 37, Part 2. The Food of Nestling Birds, Year-
book Reprint 194. Birds in their Relations to Man, pages 156-173.

PART V

FRIENDS AND FOES AMONG THE
MAMMALS

THE BOOKLET ON MAMMALS

It will probably be more difficult to get abundant material for this booklet
than any other. It is consequently less essential that one should be made.

The booklet may well be made up largely of the observations and experi-
ences of each pupil concerning the mammals most abundant in the locality
of the school. It may readily be enriched by the use of pictures cut from
magazines and mounted upon sheets of drawing paper.

CHAPTER XXX
The Squirrels

THE four-footed animals help to form a group called the
Mammals. Some of the wild mammals are helpful on the
farm, but many more are hurtful. The great majority of
the latter belong to the order of Rodents or Gnawing Ani-
mals, of which squirrels, rats, mice, and rabbits are familiar
examples. One of the chief characteristics of this group
is the curious front teeth which are chisel-like and continue
to grow as long as the owner lives ; they are called incisors.
The rodents have to be continually gnawing in order to
keep these incisor teeth short enough for comfort.

Nearly all the rodents feed upon plant materials, and
many of them are especially fond of various farm and
garden crops. -Some, however, as the common rat, are
practically omnivorous.

The interesting family of Squirrels (Sciuridz) includes
the True Squirrels, the Marmots, and the Flying Squirrels.
The True Squirrels are divided into three groups: the
Tree Squirrels, of which the Gray Squirrel and Red
Squirrel are familiar examples; the Rock Squirrels, of
which the Chipmunkisan example, and the Ground Squirrels
or Spermophiles. The Marmots include the Woodchuck
and Prairie Dog.

GROUND SQUIRRELS OR SPERMOPHILES

. The Ground Squirrels or Spermophiles are now classified
in the genus Citellus. They are often called Gophers,
307

308 FARM FRIENDS AND FARM FOES

although this much-abused word is more properly restricted
to the family of rodents commonly called Pocket Gophers.
These differ greatly in structure and appearance from the
ground squirrels.

The Spermophiles bear a rather striking general resem-
blance in habits to the Chipmunks. They are ground-loving,
grain-eating squirrels, varying into more than seventy
species or subspecies in the Western regions where they
occur. They are known to cause an annual loss of many
millions of dollars, chiefly through their injuries to grain
and forage crops. They have recently been suspected of
carrying germs of the deadly disease known as bubonic
plague, so that they may become a menace to human life.
. The Leopard Spermophile, also known as the Thirteen-
lined or the Striped Spermophile, is one of the most
abundant and widely distributed species of ground squir-
rels. It occurs from Michigan and Minnesota west to
the Rocky Mountains and south to Texas. It lives in
burrows about two inches in diameter and not more than
two feet below the soil surface. The length of these
burrows varies greatly ; some are mere pockets for tem-
porary shelter, while others extend horizontally for many
feet. During summer the Spermophiles come forth from
their burrows in search of seeds of weeds, grains, grasses,
the succulent root stems and leaves of clover, alfalfa, and
other forage crops, as well as grasshoppers and other in-
sects. All these materials serve for food. While some
benefit to man is derived from the grasshoppers destroyed,
it is more than counterbalanced by the injury done to
grain, forage, and other crops.

Early in autumn the Leopard Ground Squirrels store
up seeds and grain in their burrows. When winter comes,
they fall into a hibernating sleep that lasts about five

THE SQUIRRELS 309

months, after which they awake and feed upon the stored
seeds and such other food as they can find outside. Dur-
ing this spring season they dig up newly planted corn and
other seeds. The young are generally born in April,
there being six to ten in each litter.

‘In Wyoming, the Dakotas, and neighboring states the
Gray Ground Squirrel or Franklin’s Spermophile is the
most abundant species. It bears a striking resemblance to
thetree-loving Gray Squirrelof the Eastern states. It feeds
on grain and forage crops as well as upon field mice and
grasshoppers and other insects. It has also a fondness
for young chickens that makes it a troublesome neighbor
where poultry is raised.

In arid or semiarid regions where irrigation is practiced,

various species of ground squirrels do much damage to the
irrigation ditches by burrowing into them and deflecting
the water.
, Fortunately for man, these ground squirrels form the nat-
ural food of many predaceous mammals and birds. Such
animals as coyotes, badgers, foxes, and skunks feed freely
upon them. Hawks, owls, and eagles are always after
them. The general destruction of these natural enemies
has been an important reason for the increase in the num-
bers of ground squirrels.

The most practical means of: destroying these pests di-
rectly is the use of poisoned food. Grain or green alfalfa is
saturated with strychnine and placed in the burrows. Care
is always needed, however, to avoid accidents to people,
birds, and domestic animals. Precise instructions as to
the best methods may be obtained upon application to the
Biological Survey, United States Department of Agri-
culture.

310 FARM FRIENDS .AND FARM FOES

Marmots

The Marmots are represented in the United States by two
animals of peculiar interest—the Prairie Dog and the
Woodchuck. These.are grouped in the squirrel family on
account of their general structure, although different in
appearance and habits from the typical squirrels.

The Prairie Dogs inhabit a great area west of the Mis-
sissippi River from Texas to Canada. They are especially
abundant in prairie regions, where they often live in colo-
nies of many hundred families. Each family occupies a
burrow having a mound of earth at the entrance to keep
out water. The details of a typical burrow are shown in
the diagram on page 306.

The Prairie Dogs feed upon a variety of grains and
grasses. They are troublesome because of the food they
consume, the hillocks of soil they make, and the burrows
they dig. They are preyed upon by many natural enemies:
among these coyotes, wolves, foxes, owls, ferrets, and rattle-
snakes are the most important. In wild regions these
foes serve to keep their numbers reduced, but as land is
brought into cultivation the destruction of natural ene-
mies leads to the increase of Prairie Dogs. They are
readily destroyed, however, by placing poisoned grain at
the mouth of their burrows or by the use of carbon
bisulphide. *

Nearly every farmer’s boy in the eastern .region of the
United States is familiar with the Woodchuck or “Ground-
hog.” This is one of the largest of the rodents, and its
burrows are to be found on many farms in the hill regions
of the Northeastern states. It feeds ravenously upon clovers
and forage crops as well as upon beans, peas, cucumbers,
and many other field and garden vegetables. In autumn

THE SQUIRRELS 311

it develops a thick layer of fat beneath the skin and retires
to the burrow to hibernate.

Woodchucks are commonly trapped or shot, but the easi-
est way to kill them is by means of carbon bisulphide. A
little of this volatile liquid is poured upon a tuft of dry moss
or other absorbent material which is then rolled into the
burrow. The openings are now closed by sods or soil, and
the liquid will vaporize into a deadly gas heavier than air.
This gas will descend to the lower portions of the burrow
to destroy the animals that breathe it. If one is sure the
burrow is occupied by a woodchuck, its destruction is com-
paratively certain.

OBSERVATIONS FOR PUPILS

- GROUND SQUIRRELS OR SPERMOPHILES

1. What kinds of ground squirrels, ifany, are found in your locality ?
Write a short account of what you know about the most abundant
species. Follow this outline : —

Size and color.

Burrowing habits.

Feeding habits.

Crops injured.

Natural enemies.

Remedies, especially those you have seen tried.

PRAIRIE DoG AND WOODCHUCK

_ 1. If either of these animals is common in your locality, writea
brief account under the headings given above.

2. Read :—

American Animals, pages 151-159. The Destruction of Prairie Dogs, U. S.
Biological Survey, Circular 32.

CHAPTER XXXI

The Mice and Rats

Tue family of Mice and Rats is known by the technical
name Muride. It includes a great number of species,
many of which are destructive to farm crops. Among the
wellknown members of this group are the muskrats,
meadow mice, cotton rats, wood rats, white-footed mice,
and common rats.

The Short-tailed Field Mice, Meadow Mice or Voles, of
the genus Microtus, are
among the most destruc-
tive of ‘all the rodents.
Every farmer’s boy is
familiar with the appear-
ance of these little ani-
mals. Most boys have
killed many of them in
fields or meadows, and have found their rounded nests of
grasses and other fibers.

There are about seventy different forms of Meadow
Mice, but only a few are abundant and widely distrib-
uted. The one with which most people are familiar is
called the Common Meadow Mouse, and is known techni-
cally as Microtus pennsylvanicus. This little creature is
distributed over most of the United States. The typical
form is found in the great region east of the Dakotas and
north of a line running through Tennessee, while five

312

FIELD OR MEADOW MOUSE

THE MICE AND RATS 313

slightly different geographical races are scattered over the
rest of the country.

As soon as the snow disappears in early spring, it is easy
to find the winter runways of the Common Meadow Mouse
in almost any low grassland. They often cover the sur-
face with an interlacing network that shows how indus-
triously the mice have been at work beneath the snow.
Should you follow up these runways carefully, you would
probably come to shelter nests made of grasses which
served for temporary quarters through the winter. And
if you should explore late in spring or in the summer, you
would often find holes leading to the underground nests in
which the young are reared. The nests are likely to be
lined with the soft silk from the milkweed pods or the silky
seeds of cat-tail flags.

Meadow mice find their safest home along the borders of
swamps or other lowlands or in neglected meadows where
there is a rank growth of grass. The shelter of the grass
protects them from enemies and enables them to forage
far and wide. It also serves for warmth in winter and
furnishes abundant material for nest building. When the
snow is deep, however, the mice tunnel beneath it in all
directions, seeking orchards and grain fields where food
may be found.

In the matter of food the meadow mice are not very par-
ticular. They will eat almost any succulent vegetable mate-
rial. They are especially fond of the swollen roots of the
wild white morning glory, large numbers of which are often
stored in underground piles. David E. Lantz once found
a pile of these thus stored away that weighed more than
a pound. The roots, stems, leaves, and seeds of most
vegetable, forage, and grain crops are freely eaten. In
winter they find the bark of trees and shrubs one of the

314 FARM FRIENDS AND FARM FOES

chief sources of food, and in consequence they often do
great damage in orchards, especially those recently set.
Trees of good size are girdled, while small ones may have
the bark nearly all torn off the trunk. As this is done in
winter under shelter of the snow, the owner may not sus-
pect any damage until it is revealed in spring.

The Common Meadow: Mouse multiplies very rapidly.
The average is about- four litters of young each year with

Wild Morning-glory Roots Stored by Meadow Mice

about six in each litter. It has been estimated that if there

‘were no destruction by enemies, “a single pair and their
progeny: in five seasons would amount to nearly 1,000,000
individuals.” This of course does not happen because
many are killed in various ways, but the estimate shows
how rapidly these pests multiply under favorable condi-
tions.. It also indicates the necessity of providing as many
natural checks upon their increase as possible.

In. the great prairie regions of the Middle West the
Prairie. Mouse is abundant and destructive to a great
‘variety: ‘of crops. It is distinguished from the Common
‘Meadow ‘Mouse chiefly by: its shorter tail, which is not
‘much longer than the hind foot.

: The Prairie Mouse is most likely to develop in neglected
fields -and- meadows, from which it scatters into surround-
‘ing localities. In range pastures that are not closely
‘grazed; these mice are’ likely to-develop in grassy: tufts

THE MICE AND RATS 315

neglected by the stock. In orchards that are allowed to
grow up to weeds and grasses, they are also likely to de-
velop in such abundance as to injure the trees seriously
by gnawing the bark. They are often destructive to young
trees in nurser-
ies, _ especially
where clean cul-
ture is not given.

The rate of
reproduction
of the Prairie
Mouse is slightly
less than that of
the Common
Meadow Mouse,
there being
fewer young in
each litter. The
climatic condi-
tions as to
drought in sum-
mer and cold in winter, and the less general presence of
sheltering materials, also tend to check its increase. But
it often becomes far too abundant and destructive.

The runways of the Prairie Mouse and the Common
Meadow Mouse are generally made above the soil surface,
though commonly beneath the shelter of overhanging grasses
or other vegetation. This is an easy way to distinguish
them from the nearly related Pine Mouse, which makes its
molelike runways through the soil itself.

- This Pine Mouse in the typical form or that of a closely
allied geographical race, is distributed over most parts of |
the United States. It makes its home in woodlands rather

HYACINTH BULBS EATEN BY PINE MICE

Pa

316 FARM FRIENDS AND FARM FOES

than in open fields, but it habitually invades the latter in
search of food. Its journeys are made just beneath the
surface of loose soil, in a manner very similar to that of the
true mole, for which these mice are frequently mistaken.
They feed upon a great variety of roots, tubers, and bulbs,
often destroying crops in such a way that the injury is not
suspected until long afterward. They seem especially fond
of the tuberous roots of, wild violets which are often stored
up in piles in underground galleries.

NATURAL ENEMIES

Under natural conditions the rapid development of
meadow mice is counterbalanced by the fact that they
furnish a large part of the food of many carnivorous mam-
mals and raptorial birds. Next to insects, mice are the
most important item in the food of skunks. They form the
principal food of weasels and a large part of the food of
badgers and foxes.

There is little doubt, however, that the raptorial birds
are the principal natural enemies of the voles. Hawks and
owls of many kinds find in these short-tailed mice their
most important food. This is especially true of the Marsh
Hawk and the so-called Buzzard Hawks of the genus
Buteo. The latter include the Red-tailed, Red-shouldered,
and Broad-winged Hawks. These are a comparatively large
and heavy species that find field mice an easy prey. The
Biological Survey found three hundred and fifty of these
mice among the stomach contents of two hundred and
twenty-eight Red-tailed Hawks.

In comparison with their number, the owls seem even
more useful as mice destroyers than the hawks. These
birds are abroad at night when the meadow mice are most

!

THE MICE AND RATS 317

active. They are able to fly noiselessly over fields and
through woods and to gather their prey quickly in their
hooked talons. Practically all the owls feed largely upon
field mice, and several of them, notably the Screech Owl
and the Long-eared Owl, find in them their chief source
of food.

It has often happened that in certain regions the natural
enemies of the voles have been so persecuted as to become
scarce. When the checks upon their increase are thus re-
moved, the voles multiply with alarming rapidity and
become exceedingly destructive. When this occurs, the
hawks and owls from surrounding regions are attracted
to the infested locality, where they remain to feast upon
the mice. These raptorial birds are thus like a standing
army that nature moves from place to place to subdue in-
surrections. It is very foolish for man to wage war upon
this army ; he often has occasion to regret such persecution.

Various other birds are also useful as destroyers: of
meadow mice. Crows, ravens, and magpies feed upon them,
especially the young mice. Shrikes destroy great numbers.
Herons, bitterns, cranes, and gulls also feed upon them.

REMEDIAL MEASURES

The ways in which farmers may aid in keeping meadow
mice below the danger line are many. One of the most
effective is by protecting the natural enemies of the voles.
Another is that of clean culture of the places where the
mice breed and the tillage of infested fields. Much help
can also be obtained from cats and dogs that are good
mousers and from close grazing by the larger domestic
animals.

The chief means of direct destruction of the meadow
mice are traps and poisons. The so-called guillotine traps

1

318 FARM -FRIENDS AND FARM FOES

made of coiled wire are useful if placed in the runways,
either baited or unbaited, but they require constant atten-
tion. A single hawk left in peace is likely to do the work
of many traps. Poisons may also be employed, but these
should be used by persons of mature judgment on account
of the danger of injury to children, domestic animals, and
friendly birds. Specific instructions as to the best poisons
and their use may be obtained from the Biological Survey,
Washington, D.C. In some states the use of poisoned baits
is prohibited by law.

The injury done by meadow mice to trunks of trees may
generally be prevented by protecting the trunk with a
wrapping of wire screening or some other tree protector.
In many states wood veneer protectors are used to prevent
injury by “sun scald” as well as mice. There is much
evidence, also, to indicate that a simple application of the
lime-sulphur wash used against the San José scale is an
efficient protection. Tramping down the snow next the
trees also saves them from injury, but this is not always
practicable.

WHITE-FOOTED MICE

There are many species and varieties of the White-
footed Mouse. which
perhaps is the most
beautiful member of
the family. They are
all alike in having the
lower parts of the
body as well as the
legs and feet of a
i white color that con-
WHITE-FOOTED OR DEER MOoUsE trasts strikingly with

THE MICE AND RATS 319

the gray above. They live in woods and fields, making
their nests in logs, hollow trees, sheds, boxes, and almost
every other available place.
On the Western plains they
often nest in the bleaching
buffalo skulls. They are not
so distinctly injurious as are
‘the meadow mice, though
they often become locally
troublesome.

THE Rats

There is little need to di-
rect attention to the common
Brown Rat, doubtless the
most destructive species of
rodent in the United States.
It is so because of its large
size, its omnivorous feeding
habits, its rapid multiplica-
tion, and its ability to penetrate through most obstacles.
The young mature in six months, and three -or four
litters are born a year, each lit-
ter consisting of from six to a
dozen.

Rats are destructive in fields, gar-
dens, barns, cellars, storage sheds,
and houses. They feed on all sorts
of vegetable and animal products,
dead or alive. They carry germs
of diseases, and are altogether
most pestiferous creatures. War should be waged upon
them in every practicable way, and buildings should be

CORNSTALK RUINED BY BROWN
RaTs

RaT TRAP USED IN BURMA .

320 FARM FRIENDS AND FARM FOES

so concreted in cellar and basement as to prevent their
entrance.

Many good traps for rats are now available. The so-
called guillotine trap is perhaps the best. It is on sale
in various forms in hardware stores. Each trap should
be thoroughly scalded after use, in order to catch new
victims. Two ingenious forms of rat traps
are shown in the accompanying pictures.
The form used in Burma is a large earth-
enware vessel closed at the top by a board
held in place by a heavy stone. The rats
go in the small hole shown, and are unable
to get dut. Rice or other bait is put in

= the bottom of the jar. The barrel trap is

BARREL TRAP readily understood from the picture: the

FOR RATS Caer ae : :

bait is fastened in place at 4; a cleat is

nailed on at @ to hold the hinged top from going down on
that side.

OBSERVATIONS FOR PUPILS
MEADOW MICE

1. Observe the runways of these mice, especially in early spring.
Do you find any holes that go deeper in the ground ?

2. Look for trees and shrubs in which the bark has been gnawed
off by meadow mice. Make a list of the kinds of trees and shrubs.

3. What methods of preventing damage by these pests have you
known to be tried?

Read: —

» Meadow Mice in Relation to Agriculture, Yearbook Reprint 388.

RATS AND MICE
1. How can you distinguish a rat from a mouse?
2. What damage have you known rats to-do?
3- What ways have you tried to destroy rats?
Read: —
How to Destroy Rats, Farmers’ Bulletin 369.

CHAPTER XXXII

The Rabbits, Pocket Gophers, Moles, and Shrews

Tue Rabbits probably rank next to the meadow mice: as
widespread destroyers in field, garden, and orchard. In
the region east of the Great’ Plains the familiar Cottontail
or Gray Rabbit is abundant. In the Northern states the
Varying Hare or Northern Rabbit is found. In the West
some form of the large Jack Rabbit occurs, as well as vari-
ous sorts of Cottontail Rabbits. Consequently, rabbits
are found over the whole United States, and do injury
wherever abundant.

The damage done by Rabbits is due to their voracity and
abundance. “They require large amounts of food and
multiply rapidly. They eat plant products exclusively,
including bark, branches, buds, leaves, flowers, fruits, and
seeds. Wheat, oats, barley, corn, clovers, alfalfa, and other
grains and grasses are destroyed in the field. Peas, beans,
cabbage, melons, and other vegetables are destroyed i in the
garden. Bark, twigs, shrubs, and young trees are devoured
in the orchard and nursery.

With so varied a food supply, Rabbits naturally prefer
the more tender and succulent products. Consequently,
grain, forage, and garden crops, or fallen fruits are most
commonly eaten, bark, twigs, and other less edible things
being attacked chiefly iri winter or in seasons of drought.
The chief injury to orchard trees occurs in winter, when
the bark is stripped off in a characteristic manner.

In the Western alfalfa fields Rabbits are often very

321

322 FARM FRIENDS AND FARM FOES

destructive, congregating in large numbers in isolated
fields and ruining the crop. In the great melon-growing
regions they often cause the loss of crops by destroying
young cantaloupe and watermelon plants, and in gardens
everywhere they are. especially destructive to peas and
cabbage. The greatest damage in orchards is likely to be
done to comparatively young trees, although in many apple-
growing regions Rabbits are recognized as a pest always to
be guarded against.

The strong hind feet are the only weapons of offense
with which the rabbits are provided, but their structure,
habits, and instincts enable them to escape to a large
extent the attacks of their many enemies. With keen eyes
so set in the head as to include a large field of vision, with
large ears to detect the slightest sound, with a coloring
that makes them almost invisible amid their natural sur-
roundings, accompanied by an instinct to keep quiet most
of the time, and with long legs adapted to rapid running,
rabbits are well equipped in their struggle for life. For-
tunately for mankind, however, many of their -natural
enemies are able to penetrate their disguises or overtake
them as they run, so that rabbits furnish food for a consid-
erable number of mammals and birds. Wolves, foxes,
wild cats, badgers, weasels, and other carnivorous mammals
live largely upon rabbits, while practically all the larger
hawks and owls prey freely upon them. In wild regions
these various natural enemies serve an important purpose
in keeping a balance in rabbit life, but in cultivated regions
such enemies often become so scarce as to be less important.
As people learn the real value of certain hawks and owls
as destroyers of rabbits, mice, and other mammals, they
will probably learn to discriminate between friends and foes
among birds of prey.

RABBITS AND POCKET GOPHERS 323

Fortunately, rabbits are good for food, and in most regions
hunting is the chief means of keeping them in check. In
localities where jack rabbits are very abundant, many
people sometimes combine to make a “rabbit drive” in
which practically all the rabbits for miles around are driven
into a wire fence inclosure where they are killed by the
thousand.

Fortunately, also, rabbits are easily trapped. Most coun-
try boys have caught them in the figure-fourtraps. The
Wellhouse trap
is an improve-
ment upon this
and is readily
made by follow-
ing the direc-
tions at the end
of this chapter.
In large or-
chards two or
three such traps to each acre of trees will keep the rab-
bits in check so that little or no damage will be done by
them.

Rabbits are also destroyed by poisons, but this method
should only be used by men who will see that there is no
possibility of harm to children, domestic animals, or useful
birds: Injuries to trees are prevented by guards of wire
screening placed around the trunk. Various washes are
also helpful in preventing damage to trees. One of the
best of these is the lime-sulphur wash used to destroy
‘the San José scale. A liberal spraying or brushing of
the bark with this late in autumn is a protection for the
winter.

DETAILS OF WELLHOUSE RABBIT TRAP

324 FARM FRIENDS AND FARM FOES

PockET GOPHERS

The Pocket Gophers of the family Geomyidz form one
of the most vexatious groups of rodents. They are rather
small molelike creatures with a marvelous ability to dig
their way through loose soil. They live in underground
burrows and feed upon the roots of trees, vegetables, and
forage crops, as well as the leaves of many plants. They
are especially destructive to potatoes and in alfalfa fields.

The various species of Pocket Gophers found in the

GEORGIA GOPHER

United States occur chiefly in the region west of the
Mississippi River, though one is found in Georgia, Alabama,
and Florida, and another in Wisconsin and Illinois. The
Prairie Gopher is one of the most destructive species, as it
inhabits the fertile region.of the Mississippi Valley. The
Plains Pocket Gopher occurs in more arid regions west, and
the Gray Pocket Gopher is even more widely distributed
over both prairies and plains.

The structure of the Pocket Gophers admirably adapts
them to their underground life. The bodies are thickly
clothed with fine hair that repels moisture and earth; the
heads are pointed, the eyes and ears are small, the front
feet are especially adapted to digging, and the tail is so

RABBITS AND POCKET GOPHERS 325

sensitive that it is used as an organ of touch, when the
gopher runs backward through the burrows —a_ habit
that saves much trouble in turning round. Among the
most notable points of structure are the remarkable cheek
pouches that open externally.

As these gophers make their horizontal burrows, they
get rid of the soil by making holes to the surface every few
feet through which the loose earth is pushed out to form a
little mound. The hole to the mound is finally filled up
and another made farther along. In meadows and fields
of forage crops these mounds sometimes make it neces-
sary to run the mowing machines several inches above the
surface of the soil, thereby preventing the harvesting of
much of the crop. This is one of the most troublesome
effects of the work of gophers.

The Pocket Gophers work so constantly underground
that they have comparatively few natural enemies. They
come to the surface oftener by night than by day, so that
the owls catch more than the hawks. Other enemies are
weasels, and bull or gopher snakes. Each of these enter
the burrows and follow along till they find their victims.

Fortunately, the Gophers can be rather easily killed by
the use of poisons without much danger to other animals.
By punching a hole down to the burrow, with an old spade
handle having a pointed metallic tip, one can make an
opening through which small pellets of poisoned food can
be inserted in the main runways, where there will be little
danger of their being eaten by other animals. Such pellets
should nct be placed near the mouth of a burrow, because
of the danger of its being exposed where some other ani-
mal might get it. Strychnine is the poison most commonly
used, and the prepared poison pellets are on sale in many
drug stores. Great care is, of course, necessary in han-

326 FARM FRIENDS AND FARM FOES

dling this deadly poison; special pains should always be
taken that none of the poisoned materials be left within
the reach of children. ;

These pests may be caught in traps placed in the burrows.
Various forms of traps for this purpose are now upon the
market. Gophers may also be killed by the use of carbon
bisulphide, a volatile liquid that-rapidly vaporizes when
placed in the burrow. The vapor is a deadly poison and
soon kills any animal that breathes it. It is also inflam-
mable, and no fire must be brought near it.

MoLEs AND SHREWS

There isa small order of mammals called the Insectivora
or Insect-eaters. It includes the Moles and Shrews. These
animals live mostly in underground burrows and are
seldom seen except when turned over by accident. The
burrows of Moles are familiar to many people, though
doubtless the burrows of Pine Mice are often mistaken for
them. Moles feed largely upon earthworms and under-
ground insects, but are also often troublesome when they .
make their runways through lawns and gardens.

In the great order Carnivora or Flesh-eaters are found
many of the large wild mammals, such as bears, wolves,
coyotes, foxes, and badgers, as well as a number of smaller
ones, such as weasels and ferrets. Many of these are
efficient checks upon destructive rodents, but there is
comparatively little help to be expected from them in
thickly settled regions.

MAKING THE WELLHOUSE TRAP

The following directions for making this excellent rabbit
trap are given by David E. Lantz: —

RABBITS AND POCKET GOPHERS 327

“The trap is a box made of 6-inch fencing boards, old
ones being preferred. The box is about 21 inches long,
closed at the back by a board, but in front by a wire door
only. The door is hung from the top and swings inward.
A cleat at the bottom prevents its opening outward. The
trap is set and the wire door is kept open by a wire trigger
rod, held in place by two staples fastened to the top of the
box. This trigger is bent downward near the rear of the
trap and formed into a loop or a figure eight. As the rab-
bit enters the trap and crowds into the back part, it pushes
upon the loop, moves the trigger wire backward, and releases
the wire door. This falls and makes the rabbit a prisoner.
Bait may be used, but is not necessary, since the cottontail
is constantly looking for dark places to hide from enemies
or cold winds. Mr. Wellhouse uses about three traps per
acre in young orchards and many among the bearing trees.
They are regularly looked after by boys, and so effective
have they proved that no serious losses from rabbits have
occurred in his orchards. '

“The materials needed for making a Wellhouse trap are:
Four boards 1 by 6, 21 inches long; one piece 1 by 6, 8
inches long for the back; a short cleat for the door stop ;
284 inches of wire to serve for the door ; 22 inches of wire
for the trigger; four small staples for hanging the door
and trigger; and nails.”

OBSERVATIONS FOR PUPILS
1. Write or tell a story with this title: What I know about Rabbits.
2. Read:—

The Rabbit as a Farm and Orchard Pest, Yearbook Reprint 452; The Story of
Raggylug in Wild Animals [ have Known,

BIBLIOGRAPHY

Teachers or pupils may obtain the various Farmers’ Bulletins and
other publications of the United States Department of Agriculture
referred to in connection with the Observations for Pupils free of charge
on application to the Secretary of Agriculture. Each school should have
a set of the recent issues of the Yearbook of the Department and of the
Yearbook Reprints referred to in these pages.

A set of the bulletins of the State Experiment Station should also be
on file for reference, with extra copies of such as are especially useful in
connection with the subjects studied.

The following books are referred to in connection with reading for
pupils. They may be purchased through any book dealer.

INSECTS

Dickerson: Moths and Butterflies.

Howarp: Zhe lnsect Book.

KELLOGG: American Insects.

MURTFELDT AND WEED: Stories of Insect Life.
PEcKHAM: The Solitary Wasps.

WEED: Life Historiés of American Insects.
WEED: Nature Biographies. ,

Funct
DuaGcGar: Fungous Diseases of Plants.

BIRDS AND MAMMALS

EckstorM: Zhe Bird Book.

ForsusH: Useful Birds and their Protection.

Seton: Wild Animals I have Known.

STONE AND CRAM: American Animals.

WEED AND DEARBORN: Birds in their Relations to Man.
328

Acridiide, 67.
Aleyrodes, 273.
Ambush bugs, 167.
Andrenidez, 203.
Anthracnose, bean, 255.
cotton, 256.
raspberry, 256.

Ants, 169, 173.
and aphides, 92.

Aphides, 87, 95, 187.

Aphidius, 179.

Aphis, apple, 91.
corn-root, 92.
cotton, go.
dock, gr.
European grain, 89.
melon, 91.
orange, 91.
spring-grain, 87.

Aphis lions, 171.

Apide, 203.

Apina, 203.

Apple blossom, 195, 210.
bitter rot, 246.
maggot, 125.
scab, 245.
of Peru, 41.

Army worm, 107, 188.

Ascomycetes, 242.

Ascospore fungi, 242.

Asilide, 166.

Aspen, 25.

Assassin bugs, 168.

Asters, wild, 20, 23.

Bacillus amylivorus, 259.

Bacteria, nitrifying, 275.
nitrogen-gathering, 276.
symbiotic, 278.

INDEX

Bacterial diseases, 259, 273.

Bacteriosis, bean, 263.
melon, 263.

Bark lice, 82, 95.

Barley, mouse, 15.
wild, 15.

Barnyard grass, 33.

Bean blight, 263.

Bees, 203.

Beetle, asparagus, 136.
Colorado potato, 135.
cucumber, 137.
May, 131, 147.

Beetles, 131.

fr click, 134.
flea, 139.
ground, 164.
ladybird, 165.
Lamellicorn, 132.
leaf, 135.
long-horn, 140.
predaceous, 164.
snapping, 134.
tiger, 164.

Beggar ticks, 19.

Bermuda grass, 61.

Billbugs, 143.

Bindweed, black, 42.
hedge, 41.

Birch, gray, 25.

Bird’s-eye rot, 256.

Bitter rot, 246.

Blackbird, Brewer, 300.
crow, 300.
redwinged, 300.

Black knot, 242, 257.

Black rot, 251.

Blattide, 70.

Bluebird, 298.

329

33°

Blue-grass, flat-stemmed, 14.

Bobolink, 293.
Bollworm, 111.
Bombycine moths, 102, 120.
Borer, apple-tree, 140.
locust, 140.
Bottle-grass, 32. _
Bouncing Bet, 10.
Bracken, 24.
Brake fern, 24.
Brown rot, 247.
Buckwheat, wild, 42.
Buffalo bur, 39.
Bumblebees, 204.
Burdock, 7.
Bur marigold, 19.
Butter-and-eggs, ro, 11.
Buttercups, 24.
Butterflies, 97, 119.
Butterfly, Asterias, 97.
black swallowtail, 97.
cresphontes, 98.
‘mourning cloak, 98.

Cabbage butterfly, 97, 186.
clubroot, 257.
maggot, 127.
rot, 261.
worm, 97, 186.

Carabide, 164.

Caraway, 11.

Carnivora, 320.

Carrot, small, 21.
wild, 20.

Catbird, 299.

Caterpillar fungi, 272.

Cecidomyiide, 123.

Cedar, red, 25.

Cerambycidz, 140.

Chalcid flies, 152, 182.

Charlock, 33, 47.

Cheat grass, 45.

Cherry, black, 28.
choke, 28.

_ flower, 194.

Chess, 45.

INDEX ,

Chickweed, mouse-ear, 34.
smooth, 34.
Chicory, 11.
Chinch bug, 75.
fungus, 76.
Chondrilla, 19.
Chrospide, 171.
Chrysomelide, 135.
Cicada, dog-day, 78.
periodical, 78.
Cicadide, 77.
Cicindelide, 164.
Cinquefoil, common, 23.
Norwegian, 23.
silvery, 23.
Clotbur, 38.
Clover-seed midge, 124.
Clubroot, cabbage, 257.
Coccide, 82.
Cockle, 49.

|:Cocklebur, 38.

Cockroaches, 70.
Codling moth, 113.
Coleoptera, 131.
Cone-flower, 19.
Corn cockle, 49.
rootworm, northern, 137.
: southern, 138.
rust, 238.
smut, 228, 230.
stalk-borer, 112.
worm, III.
Cotton boll weevil, 144, 148.
rot, 203.
wilt, 251.
Couch-grass, 14.
Cowbane, spotted, 27.
Crab-grass, 33.
Crane flies, 125.
Crazy. weed, 26.
Cricket, black, 69.
mole, 70.
tree, 70.
Cross-fertilized flowers, 199.
Crow, 293.

| Crown gall, 267.

Currant worm, 150, 153.
Cutworms, 109.
Cynipide, 152.

Cypress spurge, 10.

Daisy, oxeye, 16.
Dandelion, 3.
Day lily, 10.
Diptera, 122, 188, 207.
‘Dock, bitter, 8.
broad-leaved, 8, 59.
curled, 8.
sour, 8.
yellow, 8.
Dodder, 53.
Dragon flies, 170.

Elaters, 134.
Elecampane, Io.
Entomophthorez, 271.
Evening primrose, 9.

False flax, 49.
Fern, brake, 24.
cinnamon, 24.
flowering, 24.
interrupted, 24.
sensitive, 24.
Fertilization of flowers, 194.
Finger-grass, 33.
Fireweed, 9.
Five-fingers, 23.
Flea-banes, 19.
Flea beetles, 139.
Flies, two-winged, 122, 188, 207.
Fly-away-grass, 32-
Foxtail, green, 32.
yellow, 32.
Fruit maggots, 125.
Fungicides, 267.

Gallflies, 152.

Gallfly, blackberry, 152.
Gall gnats, 123.
Gill-over-the-ground, 44.
Goldenrods, 23, 61.
Goosefoot, 35.

INDEX 331

Gophers, 307.
Georgia, 324.
pocket, 324.

Grackle, bronzed, 300.

‘purple, 300.

Grape mildew, 223.

Grape rot, black, 251.
brown 223.

Grape slug, 151.
Grasshopper, meadow, 69, 72.
structure of, 65. :

Ground cherries, 40.
Ground squirrels, 307, 312.
Gryllide, 69. ~

Gypsy moth, 103.

Hardhack, 13, 25, 62.
Harlequin cabbage bug, 77, 94-
Harvest fly, 78.

Hawk, marsh, 302.
moths, ror, 208.
sparrow, 202.

Hawkweed, orange, 17.

Hemiptera, 73.

Hessian fly, 123, 129.

Honeybees, 206.

Horse nettle, 39.

Horse-radish, 11.

Horseweed, 37.

Husk tomato, 40.

Hymenoptera, 149, 169.

Hyperparasites, 180.

Ichneumon flies, 174.
Insecticides, 155.
Insectivora, 326.
Insect-killing fungi, 271.
Tronweed, 20.

Jamestown lily, 41.
weed, 41.

Jimson weed, 41.

Joe-pye weed, 20.

Johnson-grass, 14, 61.

Jumping plant lice, $2.

Juniper, low, 25.

332
Kingbird, 301.

Lacewinged flies, 171.
Ladybird, Australian, 166.
Lamb-kill, 28.
Lamb’s-quarters, 35, 43-
Larkspur, dwarf, 27.
purple, 27.
Wyoming, 27.
Laurel, mountain, 28.
sheep, 28.
Leaf hoppers, 78, 94.
apple-tree, 81.
grape, 80.
rose, 81.
Leaf miners, 115, 129, 130.
rollers, 115.
Leaf roller, rose, 115.
Lemon rot, 224.
Lepidoptera, 96, 207.
Lettuce, prickly, 6.
Lima bean mildew, 223.
Live-forever; 10.
Loco weed, stemless, 26.
woolly, 26.
Locust, black, 25.
honey, 25.
yellow, 25.
Locustide, 69.
Locusts, long-horned, 69.
short-horned, 67.

Mad apple, 41.
Mantids, 71, 171.
Marmots, 310.
Meadow lark, 292.
Mice, field, 312.
meadow, 312, 320.

pine, 315. .

prairie, 314.
white-footed, 318.
Microgaster flies, 177.

Microtus pennsylvanicus, 312.

Mildew, bean, 254.

cherry, 254.
gooseberry, 254.

INDEX

Mildew, grape, 223, 254.
Lima bean, 222.
melon, 223.
onion, 223.

Mildews, downy, 219.
powdery, 252, 258.

Milkweed, 23.

Molds, ars.

Morning glory, wild, 41.

Moth, brown-tail, 106, raz.
Cecropia, 102.

Luna, 102.
Polyphemus, 102.
Promethea, 103.

Muride, 312.

Mushrooms, 215, 224.

Mustard, black, 33, 48.
English, 47.
hedge, 48.
tall, 48.
tumbling, 48.
wild, 33, 47-

Noctuide, 107.

Oak twig pruner, 141.
Oats, wild, 4, 7.
smut, 226, 229.
Old-witch-grass, 32.
Onion maggot, 128.
mildew, 223.
smut, 229.
Orange-dog caterpillars, 98.
fruit fly, 124.
maggot, 126.
Orthoptera, 65.
Owlet moths, 107.

Papilionina, 97.

Parasite, plant-louse, 178.
primary, 180.
secondary, 180.
tertiary, 180..

Parasitic fungi, 218.

Peach, leaf curl, 243.
twig borer, 116.

Peach, worm, 116.

Pear blight, 259, 263.
leaf blight, 249.
midge, 124.
scab, 245.

Pelecinus fly, 185.

Pentatomide, 166.

Peppergrass, 33.

Pheebe, 3or.

Phycomycetes, 219.

Phymatide, 167.

Physalis, 40.

Pigeon-grass, 32.

Pigweed, common, 36.
white, 35, 43-

Pine sawyer, 141.

Plantain, broad-leaved, 8.
large-bracted, 21.
natrow-leaved, 8, 22.
western, 21.

Plum, curculio, 141, 146.
pockets, 244.
pollination of, 200.

Pocket gophers, 324.

Poison hemlock, 27.
ivy, 27.

Pollination of flowers, 194.

Poppy, corn, 50.
field, 50.

Potato blight, early, 255.

late, 219.
scab, 254.
Prairie dog, 310.

Predaceous, beetles, 164, 172.

bugs, 167, 172.
flies, 168, 172.
insects, 163.

. Proctotrypid flies, 185.

Psyllidz, 82.

Puccinia coronata, 238.
pruni, 239.
rubigo-vera, 237.
Sorghi, 238.

Purslane, 35, 43-

Quack- , 14, 31, Or.

INDEX

Rabbit, cottontail, 321.
jack, 321.
northern, 321.

Radish, maggot, 127.
wild, 33.

Ragweed, 37.
giant, 37.

Railroad worm, 125.

Rat, brown, 319.

Rattlebox, 27.

Rattleweed, 27. .

Redroot, 36.

Reduviide, 168.

Rib-grass, 22.

Ribwort, 22.

Robber flies, 168.

Robin, 294, 298.

Roman wormwood, 37.

Root maggots, 126, 130.

Rose, bug, 133.
chafer, 133, 148.

Rust, apple, 238.
asparagus, 231.
cedar, 238.
clover, 234.
corn, 238.
hollyhock, 240.
oats, 238.
plum, 239.
raspberry, 239.
rose, 235.
wheat stem, 235.

leaf, 237.

Rusts, 231, 240.

St. Johnsworts, 23.

Salsify, 11.

Sassafras, 25.

Savin, 25.

Sawflies, 149.

Sawfly, willow, 150.

Scale, black, 85.
cottony maple, 83.
insects, 82.
San José, 86.

Seventeen-year locust, 78.

333

334

Sheep sorrel, 22.
Shepherd’s purse, 34.
Smut fungi, 226. ~
Sneezeweed, 27.
Soapwort, 10.

Soldier bugs, 167.

Sorrel, field,, 22.
sheep, 22.

Sparrow, chipping, 296.
English, 297.

Sparrows, 293, 296.

Spanish needles, 19.

Sphingidz, 100.

Sphinx moths, 100, 119, 208.
Pandorus, ror.

Squash, blossoms, 196, 211.
bug, 73, 94-

Squirrel-tail grass, 15.

Stick-tights, 19.

Strawberry, barren, 23.
blossoms, 198, 211.
leaf spot, 250.
wild, 23.

Sumach, dwarf, 29.
mountain, 29.
poison, 29.
smooth, 29.
staghorn, 29.
velvet, 29.

Sundrops, ro.

Sunflower, wild, 19.

Superparasitism, 181.

Sweet clover, rr.
fern, 13, 25.

Syrphide, 169.

Syrphus flies, 169.

Tachina flies, 188.

Tachina fly, large-horned, 190.

Tachinide, 188.

Tansy, 11.

Teasel, ro.

Tent caterpillars, 103, 186.

Tenthredinide, 149.

Thistle, Canada, 18.
pasture, 17.

INDEX

Thistle, Russian, 150.

Thorn apple, 41.

Tickle-grass, 15.

Tineina, 116.

Tipulide, 126.

Toadflax, 11.

Toadstools, 215.

Tomato worms, ror.

Tomato, strawberry, 40.

Tomato fruit worm, 111.

Tortricina, 115.

Tree hoppers, 79.

Trumpet miner, apple-leaf, 116.

Tumbleweed, 36.
Russian, 50.

Turnip maggot, 127.

Uredinales, 231.

- | Ustiliginales, 226.

Varying hare, 321.
Vegetable oyster, 11.
Verbena, wild, 20.
Vervain, 20.
Vespide, 170.

Voles, 312.

| Walking sticks, 71, 72.

Wasps, social, 170.
solitary, 170.

' Webworm, fall, 105, 186.

Wheat jointworm, 153.
midge, 124.

Wheel bug, 16°.

White fly fungi, 273.

White grub, 131.

White-tops, 19.

Whiteweed, 16.

Willow-herb, 9.

Wire-grass, 14.
Wireworms, 134.
Witch-grass, 14, 31.
Woodchuck, 310.

Yarrow, 1.

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