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eo. DEPARPMENT OF AGRICULTURE,

DIVISION OF ENTOMOLOGY.
BULLETIN No. 23.

RRO KR Is

OF

OBSERVATIONS AND EXPERIMENTS

IN

THE PRACTICAL WORK OF THE DIVISION,

MADE

UNDER THE DIRECTION OF THE ENTOMOLOGIST,

(PUBLISHED BY THE AUTHORITY OF THE SECRETARY OF AGRICULTURE.)

WASHINGTON:
GOVERNMENT PRINTING OFFICE,
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CONTENTS,

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IiINERODUCTION @ ncn cccec cas cece SEORERRSDDCD GO00 ROO COR GOO Bobecoacancetansse 3
REPORT ON NEBRASKA INSECTS... .- 0000 cect sccece ecee ese. Lawrence Bruner .-
REPORT ON VARIOUS METHODS FOR DESTROYING SCALE INsECTs, D. W. Coquil-

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REPORT UPON EXPERIMENTS CHIEFLY WITH RESIN COMPOUNDS ON PHYL-

LOXERA VASTATRIX, AND OBSERVATIONS MADE DURING THE YEAR, Albert

Koebele =.=. aes ets ciccre Sei BES ea ee INE wae meee omnes Seen Sate
ENTOMOLOGICAL NOTES FROM MISSOURI FOR THE SEASON OF 1890, Mary LE.
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REPORT ON THE WORK OF THE SEASON IN Iow,......-.....Herbert Osborn..
REPORT ON SOME OF THE INSECTS AFFECTING CEREAL CROPS.../. M. Webster..
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LETTER OF SUBMITTAL.

DEPARTMENT OF AGRICULTURE,
DIVISION OF ENTOMOLOGY,
Washington, D. C., January 3, 1891.
S1R: I have the honor to submit for publication Bulletin No. 23 of
this Division. It comprises the reports of the field agents of the Division
for the past year (1890), a summary of which has been included in your
annual report.
Respectfully,
C. V. RILEY,
Entomologist.
Hon. J. M. Rusk,
Secretary of Agriculture.

INTRODUCTION.

The reports of the six permanent field agents of the Division are in-
cluded in this bulletin. They are printed this year in full, but it should
be understood that they are little more than summaries of the work in
general performed by each one. Special reports upon specific subjects
have from time to time been sent in by special direction, and these
have been published in INSECT LIFE.

Mr. Lawrence Bruner, who last year reported upon the insects inju-
rious to young trees on tree claims, has the present season devoted
much of his attention to insects affecting, or liable to affect, the Sugar
beet, a crop of growing importance in the State in which he is located.
Although but one season’s collecting has been done, some 64 species
have been observed to prey upon this crop. As has been shown, nearly
all of these can be readily kept in subjection by the use of the kero-
sene emulsion or the arsenites.
Mr. D. W. Coquillett’s report is mainly devoted to methods and ap-

paratus for the destruction of scale insects by means of fumigation,
The experiments were aimed at the Red Scale, which is one of the most
difficult to treat with washes. He describes the simplified tents, the
rigging which enables them to be used rapidly, and shows the advantage
of excluding the actinic rays of the light. Judging from recent Cali-
fornia newspapers the use of this method of fighting scale-insects is
rapidly increasing and the comparatively expensive apparatus is al-
ready owned by a large number of fruit-growers. This improved
method is the legitimate outgrowth of experiments which we instituted
at Los Angeles in 1887, and possesses the advantage over spraying that
itecan hardly be done ina slovenly manner. If used at all its effects
are nearly complete.

Mr. Albert Koebele, while reporting upon a number of interesting
fruit pests, notably the Tent Caterpillars of the Pacific slope, and a
- Noctuid larva which destroys the buds of certain fruit trees, devotes
most of his report to the description of certain tests, which I directed
him to make with different resin compounds against the Grape Phyllox-
era in the Sonoma Valley during September and October of the past
year. The results have been fully as satisfactory as we anticipated, and
the economy of the process is very striking, labor being practically the

only expense.
7

8

Miss Mary E. Murtfeldt reports upon the insects of the season in
eastern Missouri, and also gives the results of experiments which she
has made with certain insecticides submitted to her from this office for
trial. She also presents descriptions of four Microlepidoptera, which
are new in the role of feeders upon Apple.

Prof. Herbert Osborn reports upon the insects injurious to forage.

crops, meadows, and pastures in his State. His report last year was
mainly taken up with the consideration of the Leaf-Hoppers, to which
he gives some further consideration this year, adding some notes on

locusts and crickets. He presents also a series of miscellaneous obser-

vations.

Mr. F. M. Webster devotes his report mainly to the Hessian Fly, dis-
cussing the number and development of broods, the effect of the larve
upon plants, the effect of the weather on the development of the fall
brood, and preventive measures. He also gives some notes upon three
of the species of Plant-lice, found commonly upon wheat.

In presenting this bulletin for publication, I desire to thank these
agents for the care with which they have followed out instructions and
for the intelligent manner in which they have conducted these investi-
gations. |

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REPORT ON NEBRASKA INSECTS.

By LAWRENCE BRUNER.

LETTER OF SUBMITTAL.

LINCOLN, NEBR., October 16, 1890.

Str: Herewith is submitted a report of my work in Nebraska for the yearas special
field agent of the Division of Entomology of the United States Department of Agri-
culture.

In addition to my observations on the general insect depredations within the State,
I have incidentally given some time to the study of such insects as were taken upon
the sugar and other beets during the summer,

This special study was undertaken at the suggestion of our experiment station
director, who was quite anxious that ‘‘ beet insects” should be made the subject of
a special bulletin to be issued from the station some time during the coming winter.
I accordingly include herewith a brief summary of the results of this special study.

Yours truly,
LAWRENCE BRUNER,
Field Agent.
Prof. C. V. RILEY,
U. S. Entomologist.

The past summer has not been particularly noted as one in which
insect depredators were especially abundant or destructive to the vari-
ous crops that are raised in the State. In fact, taking the State as a
whole, the injuries from this source have been rather less than is usually
the case. No one species, so far as I have been informed, has been a
pest during the year. The Corn Root-worm (Diabrotica longicornis),
while it has spread some since my last report, was much less abundant
than last year. Cut-worms did not appear in early summer So univer-
sally over the State, nor did they do anything near the damage they
did the year past. No Army-worm depredations have been reported at
the station, nor have any come to my own observation; while the Corn
Ear-worm (Heliothis armigera) has been less destructive in most portions
of the region along the Missouri River.

If any one insect has been on the increase and has caused more in-
jury than usual, it was the almost universal Codling Moth (at least
universal wherever apples are grown or eaten). But if this insect has

become apparently more widespread within this region than it was
9

ay)

formerly, it is quite consoling to know that the warfare against it has
also become more general. Almost every fruit-grower has at last come
to the forced conclusion that warfare against this insect, at least, has
become an absolute necessity, and has accordingly instituted a rigor-
ous fight against it. The arsenious spray is the almost universal
remedy resorted to with our fruit-growers here in Nebraska, as it is
in other localities. Hither London purpleor Paris green are the poisons
used, and where applied properly always result favorably to the or-
chardist.
THE GREEN-STRIPED MAPLE WORM.

The Green-striped Maple-worm (Anisota rubicunda) appeared quite
numerously again in the towns and cities of Nebraska, and has done
much injury to the Soft Maples (Acer saccharinum) growing along their
streets. Here in Lincoln, the first or spring brood of larve-was suffi-
ciently numerous to defoliate many of the largest trees before they
had become fully matured, and in that manner proved to be quite
effectual towards self-extermination. Many of the larve actually
starved to death; while others were so weakened from starvation that
they either died in the chrysalis state, or else were so exhausted when
they emerged as moths that there was but little egg-laying for a Ssec-
ond brood. Some of the neighboring cities and towns were less for-
tunate, and had a much more plentiful fall brood of the larvae, and
hence will be well supplied with the insect next spring unless something
unforeseen prevents it.

Considerable has been done in the way of remoniee by the citizens of
Lincoln against the second brood. Many of the moths were gathered
and destroyed before they had time to deposit their eggs and later on
in the season spraying the trees with London purple and Paris green
was resorted to with good results. |

While a moderately dry summer usually has the tendency to increase
the number of most of our injurious insects, several such years imme-
diately following one another have the opposite effect. So it has been
with the summer which has just closed. The drought was so very
marked that even the more hardy insect life was sensibly affected by
its severity. Such species as had been favored by the seareity of their
more frail parasites during several years of moderate drought, this year
were themselves, to a certain degree, sensibly affected by its continu-
ance and severity.

LOCUSTS OR GRASSHOPPERS.

Locusts or grasshoppers of several species were quite numerous in
certain localities, especially in cities away from the destructive influ-
ence of fowls and such other predaceous animals as are always at hand
in the country ready to “ gobble up” various insects. These locusts did
some damage, of course, but not nearly so much as was done by them

EL

last year. Whether this decrease in their numbers has been due to
parasites or to disease, I can not say. |

One noticeable fact in connection with the subject of insect depreda-
tions, in this particular region at least, is the growing interest which
the general public is taking, and the tendency on the part of the people
to help themselves against this host of insect enemies which is assailing
them on al} sides. Whether this interest is traceable to any particular
source, or whether necessity is the awakening factor, I can not say. I
trust, though, that my work in this direction has not been entirely in
vain.

BEET INSECTS.

Fiver since the Sugar Beet industry was first agitated here in the
West, and now especially since the project has assumed such a prac-
tical form, it has become of general interest. For several years now the
cultivation of the sugar beet has been a theme for much speculation,
and to some extent also of experimentation. Now that a large factory
has been built at Grand Island in this State, the sugar beet is to be one
of our regular crops year after year. It will no longer be a plant that
is grown out of mere curiosity or simply for experimentation.

It has been ascertained in connection with the culture of the sugar
beet that certain insects show a tendency to attack and injureit. In
this respect the beet is not any different from other cultivated plants;
or, for that matter, wild or native ones also. In fact, it is too evident
that certain ones of these insect enemies seem to prefer this ‘‘*new”
crop to any of these which have been cultivated in the same region for
a considerable time.

It was therefore thought here at the experiment station, early last
summer, that it might be well, as far as practicable in connection with
other lines of work, to give some attention to these insect enemies of
the sugar beet. Accordingly the following “press bulletin” was sent
out over the State:

SUGGESTIONS IN REGARD TO THE SUGAR-BEET CULTURE.

Reports from the sub-stations established in the spring by the State Experiment
Station for the purpose of determining the effect of the varying conditions of the
soil and climate on the growth of and the production of sugar in the Sugar beet are
in the main good.

In many places, especially in the extreme western part of the State, beets have
suffered from hot weather and a lack of rain; asarule, though, they seem to withstand
these unfavorable conditions as well as corn and better than small grain.

From some points reports tell us that insect enemies have begun their ray-
Aes Aho

As there are several kinds of insects that attack the beet, and as they have already
been reported as having begun operations, it seems the proper time to begin to learn
something of their appearance, habits, and the best means of meeting their advances.
To this end the beets should be watched very carefully, from day to day and at dif-
ferent times of the day, and even in the evening, for any insect, bug, or worm that
seems to have an interest in them; search the leaves, pull up the beets and search the

12

roots and the top layer of the soil, and when any marauder is found send it to the
experiment station for study and identification.

Directions for sending such specimens I copy from Bulletin XIV on “ Insects Inju-
rious to Young Trees on Tree Claims,” just issued:

‘‘ Whenever possible, insects should be packed alive in some tight tin box—the
tighter the better, as air-holes are not needed—along with a supply of their appro-

priate food sufficient to last them on the journey; otherwise they generally die on -

the road and shrivel up.

‘*Send as full an account as possible of their habits; what part of the plant they
infest, time of day when they are most active, amount of damage done, ete.

‘*Packages should be marked with the name of the sender and should be addressed
to the entomologist of the Agricultural Experiment Station, Lincoln, Nebr.”

It will aid very materially in forming conclusions if all people who have planted
seed this season will send from time to time reports of the conditions of their beets
to the experiment station,

Address:

H. H. NICHOLSON,
Agricultural Experiment Station, Lincoln, Nebr.

The very dry summer may have had considerable to do towards

influencing much of the insect injury to the beets grown within the

region designated, and some species of insects may have worked upon _

this plant that ordinarily would not have done so. In many localities
various insects were observed to congregate among the leaf stems just
above the ground that could not have been there for mischief, since
they were such forms as do not feed upon growing plants. Especially
was this true in portions of the State where the drought was severest
and where other refugees from the burning sun and parched soil were
scarce or entirely wanting. In many of these localities a great variety
of insect life was always sure to be found hidden away during the day-
time in such places. Not only beetles but also representatives of such
other orders as the Hymenoptera, Hemiptera, Neuroptera, Orthoptera,
Diptera, and Lepidoptera were quite common in such localities. Even
many water-inhabiting forms frequently occurred in company with the
others.

Of course all of these insects that were found on or about the roots
of the beets were sent in to the station both by the field agents and
by the various correspondents, who took an interest in the investiga-

tions under way. To separate most of these “refugees” from such-

other forms as might possibly be there for mischief was, of course, quite
easily done at the station by those who were accustomed to the habits
of most of the insects under consideration. A few of them were, how-
ever, more difficult to single out, and required special study to decide
positively, which in nearly every case was accomplished.

In the study of this subject it was quickly demonstrated that almost
all of the insect enemies of the sugar beet, as well as of the common
garden and other varieties, were either weed feeders or else were such

as are very general feeders. It was also ascertained that nearly if not -

quite all of the insects of whatsoever description that attack other

13

Chenopodiaceous plants, as the various species of “tumble weeds,”
the “pig-weed,” Atriplices, etc., the purslane and other juicy weeds,
as also many of those that attack the various Crucifere and Solanacex,
will also feed upon the beet. Not a single species of insect has thus
far been reported by any of the agents of the station, or by correspond-
ents, that is exclusively a beet feeder. Every one of them has been as-
certained to attack some one or more of the other plants that are also
common to the region. Only a very few species have appeared in num-
bers sufficiently great to be what could be termed ‘ destructive” to the
beet within the region covered by these studies or investigations; and
these few are of such a nature that they can be readily combated.

Iu their modes of attack upon the beet these various insects, so far
as they have been studied, are either leaf-feeders or root-borers, 7. e.,
they either attack the foliage which they devour or from which they
suck the juices by inserting their beaks, or they bore into or gnaw the
roots. Later on in our investigations we may find that there are others
that will attack the seeds and seed stems. In either of the former cases
the result is an injury to the beet, whether it is being cultivated for the
table, for feeding to stock, or for the manufacture of sugar. Should
future study reveal others that attack the seed of the beet these latter
would of course be of direct injury to the seed industry since much
seed will necessarily have to be raised to provide for the large crops
that are required each year for sugar.

Having now become fully convinced that the cultivation of the Sugar
Beet is not without its drawbacks here in the West, and that there are
insects which we must contend against and overcome in raising this
crop, aS well as in the raising of corn, wheat, and potatoes, we see
the necessity of beginning our fight at once if we would prevent much
future loss.. By prompt action in the beginning, when the enemies are
few in numbers and less generally distributed, we will have a much
easier time of it; besides, our losses from this cause will be infinitely
smaller thau if we neglect them and permit them to go on increasing
and spreading unmolestedly.

The following list embraces all such species of insects as were either
found to injure the beet here in Nebraska or else have been recorded
by others as attacking this plant within the region referred to:

LIST OF BEET INSECTS.

Species that attack the Leaves.
LEPIDOPTERA.

1. Spilosoma virginica, Fab.—The larva of this very common insect, is one of
the first noticed to injure the beet. It also infests a large number of other
plants.

2. Spilosoma isabella, Abb.—The larva, like that of the preceding, attacks the beet
and many of our common weeds.

3. Mamestra picta, Harr.—Larva occasionally attacks the leaves of beet and other
garden plants.

6.

10.

11.

12.

13.

16.

Ihe

18.

19.

20.

21

22,

14

. Eurycreon rantalis, Guen.—The larva of this small Pyralid moth is one of our

most destructive beet insects. It is the oneusually known as the Garden Web-
worm; and also attacks a number of other plants among which are the ‘‘ Pig-
weed,” the tumble weed, purslane, etc.

. Mamestra trifolii, Rott.—Larva quite common on beets; and sometimes doing

considerable injury by gnawing away the leaves and the entire tops of small
plants. Also a purslane insect. .

Plusia brassice, Riley.—The larva occasionally attacks the beet, but more com-
monly the turnip, cabbage, and other Crucifere.

. Deilephila lineata, Fab.—Larva found feeding on beet leaves in Lincoln, Nebr.,

by Mr. H. Marsland. <A very common purslane insect.

. Copidryas gloveri, G. and R.—Taken several times on the leaves of beets which it

had eaten more or less. An abundant purslane moth.

. Agrotis, spp.—Several species of these ‘‘ cut-worms” are occasionally quite de-

structive to the beet while it isstill small, They work more or less all summer,
but are most destructive early in the year. They cut off the plant just at or a
little below the surface of the ground. Some of them also work upon the leaves
above the ground.

Teucania unipuncta, Haw.—The Army Worm, when it is abundant, does consider-
able damage to beets and other garden plants by eating their foliage.

Botis pesticata, Grt.—The larva of this moth is said to be quite destructive to a
number of plants here in the West. ‘‘In 1873 we found the larve feeding
upon Helianthus, Ambrosia, potatoes, and beets, skeletonizing and ruining the
plants for miles along the Neosho Valley and throughout Kansas,” writes Pro-
fessor Riley in the U. S. Agricultural Report for 1883,

ORTHOPTERA.

Melanoplus femur-rubrum, DeG.—Occasionally injuring the leaves of beets and
other vegetables.

M. atlanis, Riley.—When common, a general feeder, at least upon the products
of the garden and farm—beets of course included.

. MW. spretus, Thos.—Attacks the beet during times of invasions. Sometimes en-

tirely eating away the leaves and portions of root that ee from the
eter

M. differentialis, Thos.—When plentifui it occasionally does some injury to the
foliage of the beet and other garden plants.

M. bivittatus, Say.—Where beets are planted on low ground or are growing
close to some rank vegetation, it attacks their tops, but never does much
damage.

Dissosteira carolina, Lin.—Found feeding upon the tops of sugar beets during the
month of July, at McCook, Nebr.

Trimerotropis latifasciata, Scudd.—Taken in company with the preceding, also
feeding on sugar beets.

Spharagemon equale, Scudd.—Several specimens were received during the sum-
mer from McCook and Ravenna, Nebr., with the accompanying statement to
the effect that they fed on the sugar heen

Pezotettix olivaceus, Scudd.—I have seen this hopper in beet fields several times
under such circumstances as led me to think it feeds upon that plant. It is also
quite partial to Helianthus and Chenopodium,

COLEOPTERA.

Diabrotica 12-punctata, Oliv.— Quite common on the leaves of beets, which it in-
jures by gnawing holes in them.

Disonycha triangularis, Say.—The beetle feeds upon the leaves of beets and other
Chenopodiaceous plants. Sometimes quite common here in the West.

26.

27.

28.

29.

30.

31.

32.

33.

34,

30.

36,

37.

38.

15

. D. cervicalis, Lec.—Has similar habits to the preceding, but is less abundant.
. D. canthomelena, Dalm.—Common on beets and other Chenopodiaceous plants,

the leaves of which it riddles with holes.’

. D. crenicollis, Say.—One of the 5-lined flea-beetles that occur here in moderate

- numbers; is also occasionally taken on beet leaves at Lincoln, Nebr.

Systena frontalis, Fab.—Found feeding upon beet leaves on the College farm, Lin-
coln, Nebr.; also on the leaves of Hibiscus militaris at West Point, Nebr.

S, teniata, var. blanda, Melsh.—A very numerous species in all parts of the State
from which beet-feeding insects have been received. It literally riddles the
leaves of beets with pit-like holes, in some instances entirely destroying the
leaves of quite large plants. I have also taken it upon white clover, purslane,
and amaranthus. This is lable to be one of our most destructive beet insects
here in the West, especially in Nebraska.

Psylliodes convexior, Lec.—Another of the flea-beetles that is very abundant on
the leaves of beets in some portions of Nebraska, and which works in a soine-
what similar manner to the preceding.

Chetocnema denticulata, Illig.—f found still another of our small flea-beetles at
work on the beets growing on the State farm here at Lincoln, although in much
fewer numbers than either of the two species preceding. __

Epitrix cucumeris, Harr.—This small flea-beetle was found to be quite abundant
at Ashland, Nebr., where it was taken by Mr. T. A. Williams, upon the potato,
Solanum nigrum, and the beet, the leaves of all of which were more or less
closely riddled with holes.

Epicauta pennsylvanica, DeG.—This black blister-beetle injures the leaves of quite
a number of plants, prominent among which are the potato, ‘‘ pigweed,” and
beet. It has been received at the station from central and western Nebraska
as one of the most destructive insects attacking the plant.

Epicauta cinerea, Forst.—Another of these blister-beetles was found here at Lin-
coln by Mr. Herbert Marsland, who said it almost ruined a-small bed of beets
growing in his garden. I have also collected the same species from one of the
wild beans and several other native plants.

Epicauta maculata, Say.—This insect has been received from Medicine Lodge,
Kans., and from Grant and Neligh, Nebr., where it was found to injure the
sugar beets by feeding on the leaves. It isa very common insect here in the
West upon quite a number of the Chenopodiaceous plants, and especially upon
the various species belonging to the genera Chenopodium and Atriplex.

Epicauta vitiata, Fab.— This striped blister-beetle is also a beet insect; and has
been received from Ogalalla, this State, where it was reported as doing much
damage to sugar beets. It also is quite ageneral feeder. Among its food plants
are to be mentioned the Solanacesx, some of the Leguminose, and I have found
it to be quite destructive to several of the Sagittarie.

Epicauta cinerea, var. marginata.—This large black blister beetle also frequently
gathers upon vegetables of different kinds in the semi-arid regions east of the
Rocky Mountains, but chiefly upon beans. I have taken it on beets once or
twice here in Nebraska.

Cantharis nuitalli, Say.—During the late summer and early fall of 1888 this in-
sect was very destructive to garden plants, beets included, in the Black Hills
of South Dakota. It also abounds in the western and northwestern parts of
Nebraska.

Colaspis brunnea, Fab.—This small leaf beetle, which appears to be quite a gen-
eral feeder, has been taken on several! different occasions upon the beet both by
zinselt and different ones of the field agents, and also by some of the correspond-
ents.

Epicerus imbricatus, Say.—The Imbricated Snout-beetle has been known to attack
the beet among the many other plants upon which it feeds. It is a general
feeder.

39.

40.

Al.

43.

44,

46.

49,

ol.

16

Centrinus penicillus, Hbst.—Another of the Snout-betiles that attack the beets
here in the West is the one known to the entomologist by theabove name. It
gnaws small holes in tbe leaf-stem, and when numerous does considerable harm
to the plants attacked. Whether or not the insect breeds here I was unable to
ascertain.

C. perscitus, Hbst.—Still a third species of weevil was found upon the beets grow-
ing on the Statefarm. It isa much commoner insect than penicillus, and works
in a similar manner upon the leaf-stem.

Apion, sp.—This little Apion was taken on the leaves of beets here at Lincoln on
two separate occasions.

2. Doryphora10-iineata, Say.—The Colorado Potato-beetle was brought into my office

at different times during the summer by those who reported its having been
captured on the leaves of beet which it was “ certainly eating.”

HETEROPTERA.

Blissus leucopterus, Say.—The Chinch Bug has quite frequently been taken by
me upon beet tops in company with several others of the plant bugs. Whether
or not it was there only temporarily, I can not say; but suppose it was, since
all of our leading economic entomologists assert that its food-plants are limited
to the grasses.

Piesma cinerea, Say.—A very common bug on the beet and various others of the
Chenopodiaceous plants. Sometimes doing much damage to the leaves of the
former.

. Nysius angustatus, Uhl.—Another bug that often gathers upon the beet and other

garden plants is what is called the False Chinch-bug. When numerous it
often does considerable harm to the plants which it attacks. Itis also one of
the weed insects that enjoys a wide range.
Geocoris bullatus, Say.—The Large-headed False Chinch-bug, or Purslane Bug, is
also much addicted to infesting the beet here in Nebraska. In fact. it has been
_received from all over the State as one of the commonest of insects infesting
the beet. It is also a great weed bug.

. Trapezonotus nebulosus, Fall.—This bug also frequents the beet and several other

Chenopodiaceous plants. It is especially partial to the Pigweed (Chenopo-
dium album) here in Nebraska.

. Emblethis arenarius, Linn.—Taken several times on the beet in company with the

preceding. This insect also is a frequenter of localities where Chenopodium al-
bum is growing. The species also occurs about the roots of ‘‘ Stink Grass”
(Eragrostis major).

Iygus pratensis, Linn.—Probably one of the most general feeders among the true
bugs, and sometimes a very destructive enemy of the beet. It occurs through-
out the entire North American continent in the temperate regions.

. Luthoctha galeator, Fab.—This bug has also been taken several times on the beet

in the vicinity of Lincoln, Nebr. I have collected it also from the wild cucum-
ber (Echinocystis lobata).

HOMOPTERA.

Agallia siccifolia.—This little leaf-hopper, which seems to be especially partial to
the different species of Amarantus and Chenopodium and allied weeds, is also
equally fond of the beet, at least such would appear to be the fact, judging from
the large numbers of the insect that are invariably to be found upon this plant
all through thesummer. It occurs in all stages.

2. Immature forms only.—Found in moderate numbers on the sugar beet at Grant,

Nebr., a rather large leaf-hopper, which also occurs upon the Amarantus and
Chenopodium.

17

53. Allygus sp.—This prettily marked leaf-hopper is very partial to Chenopodium al-
bum, on the under side of the leaves of which it breeds throughout the summer.
This insect also attacks other species of the same genus, those of the genera Ama-
rantus and Montilia, etc. Besides these it is very frequently found on the beet.
Characteristic marks of its presence are the rather large purplish spots that are seen
upon the leaves of plants that have been punctured by its beak. :

54. Erythroneura sp.—Another small, slender, green leaf-hopper that is occasionally
met with upon the beet.

5d. Athysanus (? sp.).—Still another of these leaf-hoppers that is found upon the beet.

56. Liburnia intertexta.—There is still a sixth of these leaf-hoppers that has been taken
on the beet here in Nebraska; and which presumably also does some injury to that
plant by sucking its juices.

57. Aphis atriplicis, Linn.—Mr. T. A. Williams tells me that he has taken this plant-
louse on the beet at Ashland, this State, where it was quite common during the
year.

58. Aphis cucumeris, Forbes.—This past summer Mr. Williams also took what he de-
termined to be the Aphis cucumeris, Forbes, breeding quite abundantly upon some
beets that grew right by the side of some cucumber vines that had been infested
by the same insect.

59. Siphonophora pisi, Kalt.—The same gentleman tells me that he has also taken the
common garden aphid here at Lincoln, on the beet. He found it in the pupa and
winged stages.

Species that attack the Root.
COLEOPTERA.

60. Ligyrus gibbosus, De G.—This beetle has been quite destructive to the sugar beet
over limited areas towards the western part of the State during the present season.
It attacks the root, into which the mature insect gnaws great holes, sometimes
entirely imbedding itself. It worked most on old ground and where irrigation was
resorted to. It worked on the roots from the surface to a considerable depth but
most at about 3 or 4 inches below the surface. In some instances it reached a depth
of fully 7 inches below the surface.

61. Lachnosterna fusca, Froh.—Not unfrequently the common white grub attacks the
roots of the beet, and does injury to the plant in that way. There are very likely
several kinds of the ‘‘ grub” that are concerned in these attacks, since almost every
locality has its particular species of ‘‘ June bug” that predominates in numbers.

62. Wire Worms.—Several of the larve of ‘‘ snapping beetles,” or click beetles, are
also to be charged with injuring the roots of beets in some localities.

63. Unknown larva.—On two different occasions during the past summer I found beets
that had been attacked by some unknown larva just below the surface of the
ground, and from which the depredator had already escaped. The work resem-
bled that of an insect that works in the roots of different ‘‘tumble weeds” and
causes them to break off. The larve are rather short, thick, whitish grubs with
brownish heads, about one-fourth of an inch in length, slightly largest in the mid-
dle; possibly the larva of some snout beetle.

UNCERTAIN.

64. Silpha opaca, Linn.—This insect has been taken several times by me in beet fields,
and in gardens where beets were growing. In Europe the insect is said to be quite
injurious to the beet crop, by attacking and devouring the leaves, Whether or not
it has the same habit in this country I can not say.

In addition to the above list of insects that are known to actually
attack one or the other varieties of beet there are several others that
25910—Bull. 23——2 |

18

have been taken so frequently upon that plant, and under such pecu.
liar circumstances, that they, too, may prove to beits enemies. Among
these latter I would mention several of the Kleodes, one Collops, and
several Diptera.

REMEDIES THAT CAN BE USED AGAINST BEET INSECTS.

It will be quickly seen by any one who has taken the pains to go
over the foregoing list, that in nearly every case, at least so far as men-
tioned here, the insect enemies of the beet are identical with those that
work upon our common garden weeds, or else they are such as are very
general feeders. It will also be observed that most of them are
leaf-feeders; 2. €., they nearly all attack that portion of the piant
above ground. These being the facts in the case, the remedies that at
once suggest themselves are simple. . A spray of some kind seattered
over the plants will be effectual as well as economical. The beet tops
are seldom utilized for food, either for man or beast. Hence for pro-
tection against insects with gnawing mouth parts that attack them an
arsenical spray can be used, whilst for such as receive their nourish-
ment by means of a sucking mouth the kerosene emulsion will answer
the purpose. This iatter remedy will also be effective against No. 27,
as has been demonstrated by actual experiment by at least one of our
correspondents, who writes that ‘‘The kerosene emulsion which you
directed me to try on my beets against the flea-beetles was a perfect
success.”

A direct as well as useful remedy is the careful destruction of all
such weeds as furnish food for the same insects that attack the beet.
Clean culture in this case becomes doubly necessary. First, to prevent
the appropriation by the weeds of nourishment that should be taken by
the beets, and secondly, to give less room for the propagation of inju-
rious insects.

REPORT ON VARIOUS METHODS FOR DESTROYING SCALE
INSECTS.

By D. W. CoQuiLLEettT, Special Agent.

LETTER OF SUBMITTAL.

Los ANGELES, CAL., October 8, 1890.

Str: I herewith submit my annual report for the season of 1890. The Australian
lady-bird (Vedalia cardinalis Mulsant) recently introduced by this Division, success-
fully survived the winter unprotected out of doors, and as early as the month of
March I was able to distribute several colonies to those requesting them. Lest this
species, after exterminating the Fluted or Cottony-cushion Scale (Icerya purchasi
Maskell) should become extinct on this coast, our State Board of Horticulture, at the
suggestion of its president, Hon. Ellwood Cooper, has erected two propagating
houses over two large orange trees belonging to Col. J. R. Dobbins, in the San Ga-
briel Valley ; in these houses the Vedalias are to be propagated and distributed to
those requiring them. At the present writing it is no easy matter to find a single
living Icerya anywhere in this part of the State, although in the early part of the
season they appeared in limited numbers in a great many places; later in the season
the Vedalias also appeared in considerable numbers, and by sending colonies of these
to the different localities where the Iceryas had appeared, the latter were effectually
held in check.

The Red Scale (Aspidiotus awrantii Maskell), so destructive to Citrus trees in certain
jocalities, is rapidly reduced in numbers through the agency of the treatment with
hydrocyanic acid gas, described in my previousreports. This treatment is now being
largely used fer the above mentioned purpose, and is giving far better results than
have ever been obtained by the use of any kind of a spray ; numerous instances have
occurred where, upon large Citrus trees treated with this gas, neither myself nor other
parties were able to find a single living Red Scale, either upon the bark, leaves, or
fruit—a result which so far as I am aware has never been obtained by the use of any
kind of a spray.- The cost of treating trees with the gas is scarcely greater than that
of using a spray, while the method has been so greatly simplified that trees can now
be treated with the gas very nearly as rapidly as they can be sprayed. Ihave not as
yet learned that any person, or even a single domestic animal, has ever been acci-
dentally injured either by the gas itself or by the materials used in producing it. All
of the objections which at first were urged against the use of this gas—the danger of
being poisoned by it or by the chemicals used, the great expense attached to its use,
and the impracticability of operating the tents—have finally been overcome, and the
treatment is now in successful operation.

In my last report I gave an account of the spraying of a number of orange trees
at Orange according to instructions. These trees were not again sprayed until the
lapse of a little over one year. At this latter date the trees were again badly infested

19

20

with the Red Scale ( Aspidiotus aurantii Maskell), although these were not so numer-
ous as they were at the time that I had them sprayed a little over one year previously.
The oranges when gathered in the following spring were quite free from the scales,
none of them having been rejected by the purchaser on account of being too badly
infested with these pests. Those who depend upon spraying for ridding their trees
of these scales usually spray their trees twice a year, in March or April, and again
in August or September, although some growers perform these operations only in the
autumn, the second spraying being given to the trees about two months after the
first.
During the past season I have received numerous favors from you, especially in
the matter of identifying insects, for all of which please accept thanks.
Respectfully yours, e
D. W. COQuILLETT.
Prote©. VeaniLEy,
United States Entomologist.

THE GAS TREATMENT FOR THE RED SCALE.

The process of treating trees with hydrocyanic acid gas for the de-
struction of scale insects (Family Coccidz) is now being extensively
used in southern California, not only in the orange groves, but also in
the nursery where the imported trees are subjected to this treatment
for the purpose of ridding them of insect pests. In Orange County
alone fully 20,000 orange and lemon trees have been subjected to this
treatment the present year in order to free them from the red scale
(Aonidia aurantit Maskell).

Since the year 1887 various accounts of this process have been pub-
lished in some of the Annual Reports and Periodical Bulletins of this
Department.*

But as these are somewhat scattered, and include an account of the
various improvements that have been made from time to time, I have
thought it desirable to give in this place a brief account of this process
as at present used in actual field work, including in the account such
improvements as have been made since writing up my last report upon
this subject. Briefly speaking, this process consists in covering the
infested tree with an air-tight tent and afterward charging the tent
with hydrocyanic acid gas. The material commonly used in the con-
struction of the tent is what is known as blue or brown drilling. A
few persons have used common ducking in place of the drilling, but
this is much inferior to the latter; in the ducking the threads of which
it is composed extend only lengthwise and crosswise, whereas in the
drilling they also extend diagonally—this belonging to the class of
goods to which our merchants apply the term “ twilled”—and for this
reason the drilling is both stronger and closer in texture than the
ducking.

*See Annual Report United States Department of Agriculture for the year 1887,
pp.123-142; and 1888, pp. 123-126. Also INsEcT LIFE, vol. 1, pp. 41,42 and 286; and
vol, II, p. 202-207,

21

After the tent is sewed up it is given a coat of black paint, as it has
been ascertained that tents treated in this manner last longer than
those which have been simply oiled with linseed oil. Some persons mix
a small quantity of soap suds with the paint in order to render the lat-
ter more pliable when dry, and therefore less liable to crack. Instead
of thus painting the tent some persons simply give it a coating made of
an inferior grade of glue called * size,” first dissolving this in water and
then covering the tent with it, using a whitewash brush for this pur-
pose. Sometimes a small quantity of whiting or chalk (carbonate of
lime, Ca Co;),is added to this sizing with or without the addition of lamp-
black. A few make use of the mucilaginous juice of the common Cactus
(Opuntia engelmanni Salm.) for this purpose; to obtain this the Cactus
leaves or stems are cut or broken up into pieces, thrown into a barrel
and covered with water, after which they are allowed to soak for three
or four days; the liquid portion is then drawn off and is ready for use
without further preparation. Tents which I saw that had been pre-
pared with this substance were to all appearances as air-tight and pli-
able as when prepared in any other manner.

A tent 26 feet tall by 60 feet in circumference—a size large enough to
cover the largest orange tree now growing in this State—if made out of
drilling, and either painted or sized, as described above, will cost com-
pleted about $60. Where the trees to be treated are not more than 12
feet tall the tent can be placed over them by means of poles in the
hands of three persons; to accomplish this, three iron rings are sewed to
the tent at equal distances around and 6 or 7 feet from the bottom of
the tent; immediately under each of these rings an iron hook is attached
to the lower edge of the tent. When the latter is to be placed over a
tree each of the hooks is fastened into the corresponding ring above it ;
one end of a pole is then inserted into each of these rings and the tent
raised up and placed on the tree. The hooks are then released from the
rings and the lower edge of the tent allowed to drop upon the ground.

Instead of allowing the tent to rest directly on the tree some growers
use an umbrella-like arrangement, the handle of which is in two pieces,
which are fastened together with clamps provided with pins; this
allows the handle to be lengthened or shortened according to the height
of the tree. This apparatus is put up over the tree and the tent allowed
to rest upon it. By the use of this simple device the danger of break-
ing off the small twigs on the upper part of the tree by the weight of
the tent is avoided. Mr. Leslie, of Orange, used tour tents and tent-
rests of this kind, and he informs me that with the aid of two men he
fumigated 120 trees in one night. To remove the tent from one tree,
place it over another, and charge the generator required only one minute
and ahalf. In the place of poles some persons attach a circle of gas
pipe to the lower edge of the tent; then two men, each taking hold of
opposite sides of this circle, throw the tent over the tree. Dr. J. H.
Dunn, of Pomona, informs me that four men, using six tents like the

22

above, fumigated 240 orange trees in one night, and that the average
for each night was over 200 trees, the latter being 8 feet or less in
height.

Trees over 12 feet tall will require a derrick of some kind for the pur-
pose of putting on the tent and removing it again. [or this purpose a
stout mast is erected in the center of a strong framework mounted
upon the running gears of a common farm wagon, the height of the
mast depending upon the height of the trees to be operated upon. This
mast is braced in four directions, and to the upper end of it is firmly
attached a cross-piece, extending transversely to the length of the
wagon, and long enough to reach from one row of trees to another. To
each end of this cross-piece are attached small pulleys, through which
pass ropes which are attached to the tents; by pulling down on these
ropes the tents are drawn up to the cross piece after which the wagon
is drawn ahead until the tents are directly over two of the trees to be
treated; the ropes are then let out and the tents lowered down over
the trees. The ropes are usually attached to the lower edge of the
tents as well as to their apices, and when the tent is to be taken off of |
the tree the ropes attached to the bottom of it are first pulled down-
ward, thus drawing the lower part of the tent up to the cross-piece
first, and in a measure tarning the tent inside out. But for this-device ©
it would be necessary to have the cross-piece at least twice the height
of the trees to be operated upon. This apparatus is drawn between
two rows of trees and the trees on each side of it treated with the gas.
It iscustomary for the men themselves to draw the fumigator from tree
to tree, thus doing away with the use of horses for this purpose. Stout
planks are frequently used for the wheels of the fumigator to run upon.
A fumigator of this kind, without the accompanying wagons and tents,
ean be built for about $15, it being the cheapest and simplest apparatus
ever used for this purpose. It has not as yet been patented, and is
more largely used at the present time than any other kind, operating
the tents successfully even upon the largest orange trees. The first
fumigator of this kind was built by Mr. O. H. Leefeld, a prominent
orange-grower of Orange, and a man who has had considerable experi-
ence as a machinist.

Within the past few weeks a new kind of a fumigator has been
brought out by Mr. W. H. Souther, of Covina, Los Angeles County,
Cal. This, like the preceding one, is mounted upon a common farm
wagon, and operates two tents, one on either side of it. At each end
of this fumigator are four upright posts attached at their lower ends to
the framework, which is mounted on the wagon; the outermost posts
are Shorter than the inner ones, and to the upper end of each is attached
a long spar by a hinged joint, which allows the spar to be moved back
and forth transversely to the length of the wagon. The two spars on
one side of the fumigator are connected with each other near their upper
ends by means of a wooden cross-piece, and are drawn back and forth

23

by means of ropes passing through pulleys. The tents are operated by
means of ropes, which pass through pulleys attached to the spars and
cross-pieces described above, there being five ropes attached to each
tent; one of these is attached to the apex of the tent, and passes
through a pulley fastened to the middle of the above-mentioned cross-
piece; two other ropes are attached to opposite sides of the tent, about
midway between its apex and base, and pass through pulleys fastened
to each of the spars near their upper ends; the other two ropes are
attached to opposite sides of the lower edge of the tent and pass through
pulleys fastened to each of the spars a few feet higher up than those
above described. To the bottom of the tent is attached a wooden cir-
cle in several pieces, and the two ropes attached to the bottom of the
tent are fastened to this circle; these ropes are not exactly on opposite
sides of the tent, the space between them equaling about one-third of
the entire circumference of the lower edge of the tent.

In taking the tent off of a tree the two ropes attached to the tent
midway between its base and apex are first drawn downward until their
points of attachment are slightly above the top of the tree, after which
the two ropes attached to the lower edge of the tent are drawn down-
ward until their points of attachment are drawn up against the spars
at the places where the pulleys through which these ropes pass are fas-
tened ; the lower edge of the tent at this stage will be perpendicular
to the surface of the ground, and these ropes are further pulled upon
until the spars on this side of the wagon are perpendicular to the
wagon, thus bringing the weight of the tent upon the middle of the
wagon; the spars are prevented from going over backward any farther
by the presence of the inner upright posts referred to at the beginning
of this description. When both of the tents have thus been drawn upon
the wagon the latter is moved forward until the tents are brought op-
posite the next two trees. Before the tents are again let down over
the trees the fumigator is first braced up by means of four long braces
attached to each of the four corner posts at a distance of about 8 feet
from the ground; these are attached in such a manner that they may
be swung out at right angles to the fumigator, or, when not in use, may
be swung around and loaded-upon the wagon without first detaching
them. After these four braces are in position the ropes attached to one
of the tents are let out and the tent allowed to fall down over the tree,
a guide-rope being attached to its lower edge to aid in guiding it in its
downward descent over the tree.

Mr. Souther, the inventor of this fumigator, informs me that a fumi-
gator of this kind, without the wagon and tents, could be built for about
$60. He also informs me that a patent has been granted to him upon
this fuiigator.

Besides the above fumigators I may also mention one which has been
used in a few instances with very good results. It is an extremely
simple affair, consisting of av upright post the lower end of which is

24

attaehed to a framework on a wagon or sled, while to its upper end is
attached a long stick of timber, the latter being attached near its middle
to the top of the post, like the sweep of an old-fashioned well. The
tent is then attached to one end of the sweep, and by pulling downward
on the opposite end the tent is raised up, and may then be swung
around and let down over a tree.

After the tent is placed over the tree the next step is to charge it
with the gas. The materials used for the production of the gas consist
of commercial sulphuric acid (Ky SO,), fused potassium cyanide (KCN),
and water, the proportions being 1 fluid ounce of the acid, 1 ounce by
weight of the dry cyanide, and 2 fluid ounces of water. The generator
is placed under the tent at the base of the tree; it consists of a common
open earthenware vessel. The water is first placed in the generator,
then the acid, and last the cyanide, after which the operator withdraws
to the outside of the tent and the bottom of the latter is fastened down
by having a few shovelfuls of earth thrown uponit. The tent is allowed
to remain over the tree for a period of from 15 to 30 minutes, according
to the size of the tree.

It was found by experimenting that the trees were less liable to be
injured by the gas when treated at night than they were when operated
upon in day time, and at the same time the gas is just as fatal to the
scale insects when applied at night as it would be if applied in the day
time; and indeed it appears to be even more fatal when applied at night.
This is accounted for by reason of the fact that in the day time the light
and heat decompose the gas into other gases which, while being more
hurtful to the trees, are not so fatal to insects. At night the trees are
also more or less in a State of rest, and therefore are not so liable to be
injured by the gas as they would be in the day time, when they are
actively engaged in absorbing nourishment and repiacing wasted tissue
with new materials.

Of the different materials used in generating the gas, the nae
important is the potassium cyanide; of this there are three grades:
The mining cyanide, commercial cyanide, and the C. P. (chemically
pure). Of these three brands, the mining cyanide is wholly unsuitable
for the production of the gas, and the C. P. is too expensive; the com-
mercial brand (fused) is the only one that is used for producing the
gas, but even this varies greatly in strength, containing all the way
from 33 to 58 per cent. of pure potassium cyanide. It is, therefore, of
the utmost importance that the operator should know the exact per-
centage of pure potassium cyanide that his cyanide contains, and when
large quantities of it are purchased at one time it would be advisable
to obtain one or more analyses of it by a reliable analytical chemist;
or if it is not possible to submit the cyanide to such person, an analysis
of it could be made by almost any person accustomed to the use of
chemicals or drugs.

The only substance required for this purpose is the crystals of nitrate

25

of silver (AgNO;), which may be obtained at almost any well-stocked
drug store. Dissolve the nitrate in cold water contained in a glass or
earthen vessel, using one-fourth of an ounce (Troy) of the crystals to 1
pint of water; this dissolves in a few minutes, forming a whitish, semi-
transparent solution. The cyanide, when dissolved in water, forms a
transparent, nearly colorless solution; when a small quantity of the
nitrate of silver solution is added to this it at first spreads out in a white
cloud, like milk, but it soon breaks up into small, white, floccy pisces
which gradually disappear upon being agitated, leaving the solution
nearly as transparent as at first; when more of the nitrate of silver
solution is added from time to time the above process is repeated, ex-
cept toward the last, when the cyanide solution becomes somewhat
milly, but it still remains semitransparent, permitting the operator to see
quite clearly the bottom of the vessel containing the solution. As soon
as a sufficient quantity of the nitrate of silver solution has been added
tothe cyanide solution the latter immediately becomes white and opaque,
like milk, completely concealing from view the bottom of the vessel con-
taining it. This completes the operation, and the quantity of nitrate
of silver solution used will indicate the strength of the cyanide tested,
When absolutely pure, 53 grains of the potassium cyanide dissolved in
water will require 1 fluid ounce of the above nitrate of silver solution
before the turbidity occurs, indicating that the cyanide is 100 per cent.
strong; if only one-half of a fiuid ounce of the nitrate of silver solution
produces this turbidity, this indicates that the. cyanide in only half
strength, or 50 per cent. strong; if only one-fourth of a fluid ounce is
required, then the cyanide is 25 per cent. strong; and so forth. The
nitrate of silver solution should be added to the cyanide solution very
slowly, the latter being agitated by gently shaking it each time that
any of the nitrate solution is added. Wherever any of the nitrate of
silver solution comes in contact with the skin or nails of the hand it
produces a reddish or black stain which can easily be removed by wash-
ing the stained part in a solution of potassium cyanide and water; this
will quickly remove the stain without causing any injury to the parts
affected, except, of course, when the stains occur upon a sore or cut in
the hand, in which ease it would be very dangerous to apply the cyanide
to these places.

It sometimes happens that the percentage of cyanogen (CN or Cy)is
given, instead of the percentage of potassium cyanide (KON or KCy);
but in cases of this kind the percentage of cyanide can be readily ascer-
tained by always bearing in mind that two-fifths of a given quantity of
potassium cyanide is cyanogen. Thus if a certain brand of cyanide
contains 24 per cent of cyanogen, this is equivalent to 60 per cent of
pure potassium cyanide. Potassium cyanide when absolutely pure
(equal to 100 per cent.) contains 40 per cent. of cyanogen; and, there-
fore, no grade of cyanide could contain a larger percentage of cyano-
gen than this.

26

The potassium eyanide used for producing the hydrocyanie acid gas
is principally manufactured by two firms: Power & Weightman, of
Philadelphia, Pa., and the Mallinkrodt Chemical Works, of St. Louis,
Mo. That made by the first named firm is the most largely used; when
purchased by the ton the price is 36 cents per pound for the grade con-
taining about 57 per cent of pure potassium cyanide, packages and
carriage extra. It is put up in tin cans holding 10 pounds each, and
also in barrels holding about 400 pounds each. That in the cans is
much to be preferred, since the quantity in each is so small that it will
soon be used up after the can is opened; whereas, the barrel contain-
jng so large a quantity, the cyanide used toward the last will have lost
much of its strength by contact with the air. Itis customary to weigh
out the cyanide in small paper parcels, and mark each parcel with the
number of ounces of cyanide that it contains; then when the tree is to
be fumigated it is an easy matter for.the operator to select one of the
parcels containing a sufficient quantity of the cyanide for the tree, thus
saving the trouble of weighing out the cyanide as it is to be used for
each tree. As the fumigating is done only at night the weighing of the
cyanide is frequently done by the ladies of the house upon the day pre-
ceding its use.

The quantity of cyanide to be used on each tree will, of course, de-
pend not only upon the size of the tree but also upon the strength of the
cyanide used. The following table will aid in determining the proper
quantity of each ingredient to be used on different sized citrus trees,
the cyanide being about 58 per cent pure: |

Height Diameter Sulphuric | Potassium
of tree. | of tree-top. Water. acid. cyanide.
Feet. Feet. Fluid ozs. | Fluid ozs. Ounces.
6 4 3 h 4
8 6 2 1 1
10 8 42 24 24
12 10 8 4 4
12 14 16 8 8
14 10 10 5 5
14 14 19 b 93
16 12 16 8 8
16 16 29 143 143
18 14 26 13 13
20 16 36 18 18
22 18 52 26 26
24 20 66 33 33

Not only is this gas fatal to the Red scale (Aspidiotus aurantit Mas-
kell), but also to the San José scale (Aspidiotus perniciosus Comstock),
and indeed to all of the armored scales. It is also fatal to the Brown
scale (Lecanium hesperidum Linn.) and to the Black scale (Lecanium
olew Bernard), but the eggs of this species are not affected by it.
The common Red Spider (Tetranychus telarius Linn.) and the Woolly
Aphis (Schizoneura lanigera Hausmann) are also not affected by the gas
when used strong enough to destroy the Red scale, although I have
known it to prove fatal to true spiders (species not determined). House-
flies (Musca domestica Linn.), Lace-winged flies (Chrysopa sp.?), and cer-

[tt

erat

tain kinds of Ichneumon flies (Ophion macrurum Linn.) are also de- |
stroyed by the gas. On one occasion I obtained a cluster of eggs of a
species of Psocus fly (Cacilius auwrantiacus Hagen) that were deposited
upon a leaf of a tree before the latter had been treated with the gas,
and from these eggs afterwards issued a number of parasitic flies be-
longing to the family Prectctrupide and to the genus Alaptus; but the
species is as yet undescribed. Various kinds of Lady-birds, which are
in the tree when the latter is treated with the gas, become stupefied and
fall to the ground, but finally recover and are to all appearance none
the worse for their temporary loss of consciousness. Birds, lizards, and
even barn-yard fowls sometimes refuse to leave the large orange trees
while the tent is being let down over them at night, and are therefore
inclosed in the tent and subjected to the gas; the latter proves fatal to
all of these. The small, pale yellow mites which are frequently found
on orange trees, especially beneath the dead scales, are not affected by
the gas; these have a general resemblance to the young of the Red seale,
and several operators, finding these mites still alive after the tree had
been subjected to the gas, came to the erroneous conclusion that the
gas had not been effectual, thinking that these mites were the young of
the Red scale.

From the above it will be seen that the gas treatment is not a sure
specific for every kind of insect pest, but for destroying Red scales on
citrus trees it is far superior to any other method at present known.

THE RESIN WASH FOR THE SAN JOSH SCALE.

During the past winter I carried on quite a series of experiments with
various kinds of washes for the destruction of the San José scale
(Aspidiotus perniciosus Comstock) on dormant deciduous trees, kindly
placed at my disposal by Mr. C. H. Richardson, the inspector of fruit:
pests for the Pasadena district, Mr. Richardson also aiding me in mak-
ing many of these experiments. Among all of the washes tried the fol-
lowing gave the best results:

J ROSTUD 45 a SER ACE A SSS ISS aie gs Mee ens or ree ae a aa pounds.. 30
OuHsiie soda, @0speriCeNt) ass. cence ete seca s NA Soenen Cerone
IETS) CY! 2A Se Se Bee RIE eee Oe ee pints.. 43
Wittermenomen fOnmake scsi .t Mos een wee gallons.. 100

For making 100 gallons of the above wash a kettle holding 30 gallons
will be required. Place all of the ingredients in the kettle and cover
with water to a depth of 4 or 5inches, boil briskly for about 2 hours, or
until it will dilute evenly with water, like black coffee, which it closely
resembles in color. When this stage is reached the kettle should be
filled up with water, adding this very slowly at first; the contents of
the kettle can then be emptied into a tank or other vessel, and a suffi-
cient quantity of water added to make 100 gallons. Care should be
taken not to chill the wash by adding large quantities of cold water at
one time.

28

The making of this wash will be greatly accelerated if the resin and
caustic soda are first pulverized before being placed in the kettle; if in
large pieces, a considerable length of time will be required in which to
dissolve them. Ifa sufficient quantity of water is not used at first the
materials when dissolved will form a thick, pasty mass, which simply
breaks open in places to allow the steam to escape, and pieces of the
mixture will be thrown out of the boiler or against its sides or lid by
the escaping steam. When this occurs, water should be added until
the solution boils up in a foamy mass. Whenever there is a tendency
to boil over a small quantity of cold water should be added, but not
too much, or the making of the solution will be retarded; after a few
trials the operator will learn how much water to add in order to pre-
vent the solution from boiling over and yet keep it in a brisk state of
ebullition. If it is not desired to add all of the water at the same time
that the solution is made, then enough can be added to equal two-
fifths of the quantity required; the balance of the water can then be
added at any subsequent time without again heating the solution.
Thus, if a sufficient quantity of the solution is boiled to make when
diluted 100 gallons, this could first be diluted to make only 40 gallons,
and the remaining 60 gallons of water added at any time as required.
If it is desired to use it in a still more concentrated form than this, it
need not be diluted at all after it has been boiled sufficiently, but in
this case it will be necessary to heat it again before adding the water.

On the 11th of February, between the hours of 1:30 and 4:20 p. m.
(sun shining, light breeze), I had 60 dormant deciduous fruit trees
sprayed withthe above solution. These consisted of peach, plum, apple,
pear, and quince trees; none of them had started to leaf out except the
quince, which had put forth a few leaves at the tips of some of its
branches. Each of these trees was infested with the San José seale
(Aspidiotus perniciosus Comstock) and several of them had been almost
killed by the attacks of this pest. April 23 I made a careful examina-
tion of these trees and found only a very few living San José scales;
all of thetrees except those which were nearly dead when sprayed were
now making avigorous growth. May 12 I again examined these trees,
and found living San José scales on only three of them, about half a
dozen scales on each. I made another examination on the 11th day of
June, and found a few San José scales on some of the pears on the
above trees. All of the Black scales (Lecanium olee Bernard) which
I found on these trees were dead, and their eggs were dry. July 241
again examined these trees and found three or four living San José
scales on a few pears and apples on some of the trees, but the fruit was
practically clean, whereas on adjoining trees which had not been
sprayed nearly all of the pears were very badly infested with these
scales. There was, however, a singular exception to this: A LeConte
pear tree that stood in the midst of several Bartlett and Winter Nelis
pear trees, which were very badly infested with the San José scale, was,

29

wholly free from this pest. Nor is this an isolated case, since I saw
the same thing in another pear orchard located several miles from this
one. Mr. Richardson informs me, however, that the fruit of this tree
is almost worthless.

Wishing to test the effects of the above wash on growing trees, I
sprayed a prune, peach, apricot, apple, and orange tree on the 12th day
of May, between the hours of 10 and 11 a. m., sun shining, light breeze.
I examined these on the 11th of June; on the prune all of the fruit had
dropped off, and upon one-third of the leaves were dead brown spots,
these spots not exceeding one-sixth of the entire surface of any of the
leaves; on the peach all of the fruit was dead, but still clinging to the
tree, and half the leaves had brown spots in them, these leaves being
much more injured than were those on the prune tree; on the apricot
the fruit was not injured in the least and three-fourths of the leaves
were uninjured, but the remaining leaves had small brown spots in
them, these spots not exceeding one-fifteenth of the surface on any of
the leaves; on the apple all of the fruit had dropped off and half the
leaves had large brown spots in them, these spots sometimes exceeding
one-half of the entire surface of the leaf; on the orange nearly all of
the fruit had dropped off (the young oranges being about half an inch
in diameter), but the leaves were uninjured.

This indicates that of the different kinds of fruit thus experimented
upon the apricot was the hardiest aud was the least affected by the
wash ; next to the apricot is the orange, then the prune, after this the
peach, the apple having suffered most from the effect of the wash.

The orange tree experimented upon was infested with the Yellow
scale (Aspidiotus citrinus), and also with the Black scale (Lecanium olew
Bernard), and all of these, as well as the eggs of the Black scale, were
destroyed by the wash.

According to the scale of prices furnished me by the Los Angeles
Soap Company of this city, the material for making 100 gallons of the
above wash, when purchased in large quantities, would amount to $1.14,
being but a trifle over 1 cent a gallon for the diluted wash.

The materials used in preparing the above wash are the same as
those I used in spraying orange trees last season for the destruction of
the Ked scale (Aspidiotus aurantit Maskell), an account of which is
given in my report to Professor Riley for last year, published in Bulle-
tin No. 22 of the Division of Entomology (pp. 10-14); but the spray I
then used was only three-fifths as strong as the one I used for the de-
struction of the San José scale as above described. On the 19th of
December I tested the spray of the same strength that I had used
for the Red scale on orange trees, but it did not prove fatal to all of
the San José scales that it came in contact with.

The question as to the manner 1n which the above resin spray proves
fatal to the scale insects—whether the caustic property imparted by the
caustic soda is the destructive agent, or whether it is the suffocating

30

effect of the resin and fish oil saponified by the caustic soda that pro-
duces this result—is a very important one. Quite a number of our
fruit growers were at first inclined to believe that it is the caustic prop-
erty of the wash that destroys the scale insect, and they therefore in-
creased the quantity of this particular ingredient, only to find that the
wash so constituted is not apparently more fatal to the insects, while
at the same time it is very liable to injure the fruit. My own studies
aud experiments lead me to believe that the above sprays kill for the
most part by suffocation. In the course of experimenting I found that
a wash composed of the following ingredients:

Catistic: sedaiss.c6.4;.055 esse see ee eae eae ee -..2.pounds-. 8
ROSIN 2 dod~. oS ccaecle ae Se ee Se ee > Oe eee Eee do! Saas
Water enough to make -.-.---.--..- so scctse =. Sallons== 300

did not prove fatal to as large a percnnaee of Red seas as did one con-
sisting of:

COPA CT. 1000 ie aa es ea Sr tn ee iene Be Oe aT GCS pounds.. 6
ROSIN Sus S26 3 Sow ck oe oases ae eee eee eee Pee eae see doz---5 20
Fish oil 22's sso. c Gack tee ons soa ee See ee eee a eee pints... 3
Wiaterenoug hito makes eis th peeiese Ue See eae eee gallons.. 100

Now, if it is the caustic property of the wash that proves fatal to the
scale insects, it is evident that the wash containing the largest amount
of the caustic agent would prove fatal to the largest number of scale
insects, but the reverse of this was really the case; the wash containing
the smallest amount of the caustic agent, the caustic property of which
was still further lessened by the addition of the oil, proved fatal to the
largest number of the insects. On the other hand, the addition of the
oil, while reducing the caustic property of the wash, would increase its
varnishing qualities, since it is a fact well-known to painters that the
addition of oil to a varnish improves its qualities. For these reasons
it seems quite certain that it is the suffocating properties of the wash
and not its caustic nature that cause it to prove fatal to the scale insects
which have been sprayed with it.

I have seen orange trees that had been sprayed with a wash so caustie
that it killed fully nine-tenths of the leaves on the trees, burnt the bark
brown, and caused nearly all the oranges to drop off, and yet quite a
number of the Red scale insects located on the oranges still remaining
on the tree were alive. This will show the utter uselessness of attempt-
ing to destroy the Red scale on citrus trees by the use of caustic washes.

THE LIME, SALT, AND SULPHUR WASH FOR THE SAN JOSH SCALE.

For destroying the San José seale (Aspidiotus perniciosus Comstock)
on dormant deciduous fruit trees many growers in this State use a wash
composed or the following ingredients in the proportions here given:

Sulip WUT e se Se cre aa cee, <a aie Sree eee Hh 556 GSES55 pounds... 33
TiIN@ 226 eee ace. eae So en ee eee Eee cer Roe ree eee do.... 42
Sa lU a2 csew eee wees = bas acer See te eee ne ant meena do-2s-= #20

Water enough to makes... 2-2 22 -eeeeceee sce eee eee gallons.. 100

31

All the sulphur and half of the lime are placed in a kettle and 33
gallons of water added, after which the contents of the kettle are boiled
briskly for about 1 hour; the solution will then be of a very dark brown
color and having a reddish tint. All of the salt is added to the remain-
ing 21 pounds of lime and the latter slaked, after which this slaked
lime and salt are added to the above described sulphur and lime solu-
tion and the whole then diluted with a sufficient quantity of water to
make 100 gallons; this is then strained, after which it is ready to be
sprayed upon the trees.

This does not form a perfectly liquid solution but contains a consid-
erable quantity of undissolved sulphur and lime, which soon settles to
the bottom unless the solution is stirred almost constantly while being
sprayed on the trees. It is therefore somewhat of the nature of a thin
whitewash, and the trees sprayed with it have the appearance of hav-
ing been whitewashed. On the 26th of November, at 12:45 p. m., sun
shining, light breeze, I sprayed a pear tree with a wash made according
to the above directions, the tree being very thickly infested with the
San José scale. January 15 I found 14 living San José scales on this

tree, and on the 23d of April I found several more; on the 11th of
June I found on this tree a Black scale (Lecanium olew Bernard) con-
taining healthy eggs.

I also tested this wash in the following proportions:

Sin DING ees Coa oe Ne cee cr Be ce Rae ae geet oman pounds.. 50
IDMNTNG asoSecsc edqcoe seoses S508 odbe Cognan sceeds cécorde sods ces doses. 105
SOU cho teaceeeon BeeenS BAOSSe BOSE IO ORO tO E Or EaCe ie cmriaee doa od
Witibe ren OO GO-M a KO ets 2) as je salman ce emiss e='s sas ene gallons.. 100

This was applied to a pear tree at 1 p. m., November 26, sun shining,
light breeze. On January 15 I found 6 living San José scales on this
tree, and on the 23d I found several more.

At the time of making these tests there were several green leaves on
each of these trees, but all of these were killed by the washes. The
trees otherwise were not apparently injured, and in the following spring
started into a vigorous growth which was. continued throughout the
summer. These trees were not over 10 feet tall, and were very thor-
oughly sprayed, so it seems quite certain that every scale insect located
upon them must have been covered with the wash.

The philosophy of this wash is not at present clearly understood. 1t
seems very probable however that the product of the lime and sulphur
(bisulphide of lime, CaS.) furnishes the insecticidal property, and the
presence of the salt and slaked lime simply imparts permanency to the
wash. I made quite a series of experiments with the above-named in-
eredients, with a view of ascertaining which of the ingredients were
really insecticides, but these experiments have thus far resulted nega-
tively. The following is a brief account of these experiments :

SALYT.—Experiment 229: Table salt, 19 pounds; water, 100 gallons.
I simply dissolved the salt in cold water and then sprayed the solution

2
“
ee

32

on a pear tree at 12:30 p. m., November 26, sun shining, light breeze. °
This did not kill all of the green leaves that were upon the tree. Jan-
uary 15 I found a great many living San José scales on this tree.

Experiment 228: Salt, 38 pounds; water, 100 gallons.. Dissolved the
salt in water as before and sprayed on a pear tree at noon, November 26,
sun shining, light breeze. This killed all of the green leaves that were
upon the tree. January 15, I found many living San José scales on this
tree.
Experiment 237: Salt, 60 pounds; water, 100 gallons. Dissolved the
salt as before and sprayed on a pear tree at 10 a. m., January 20, sun
shining, light breeze. April 23, I found a great many living San José
scales on this tree.

SALT AND LIME.—Experiment 238: Salt, 25 pounds; slaked lime,
84 pounds; water, 100 gallons. The salt and lime were added to the
cold water, stirred occasionally, and strained through a piece of Swiss
muslin and then sprayed upon a pear tree at 10:30 a. m., January 30,
sun shining, light breeze. April 23 I found a great many living San
José scales on this tree.

SALT AND SULPHUR.—Experiment 232: Salt, 25 pounds; sulphur,
75 pounds; water, enough to make 100 gallons. Thesulphur was boiled
for an hour in 75 gallons of water, after which the salt was added, and
the solution diluted with a sufficient quantity of cold water to make 100
gallons. After standing for a few minutes the greater portion of the
sulphur settled to the bottom, making it necessary to stir the solution
almost constantly while applying it to the tree. Sprayed on a pear tree
at 2:45 p. m., November 26, sun shining, light breeze; this killed all of
the green leaves on the tree. January 10 I found a great many living
San José scales on this tree.

SULPHUR.—Experiment 233: Sulphur, 100 pounds; water, enough to
make 100 gallons. Placed the sulphur in the water and boiled for 1
hour, then when cold, sprayed the solution on a pear tree at 3p. m.
November 26, sun shining, light breeze. ‘This did not injure any of the
green leaves that were on the tree. January 15 I found a great many
living San José scales on this tree, a smaller proportion being killed
than in either of the preceding experiments.

LimE.—Experiment 239: Slaked lime, 10 pounds; water, enough
to make 100 gallons. The lime was placed in the water, stirred occa-
sionally and in two hours the solution was strained through a piece of
thin Swiss muslin and sprayed upon a pear tree at 10:45 a. m. January
20, sun shining, light breeze. April 23, I found a great many living
San José scales on this tree.

LIME AND SULPHUR.—Experiment 240: Quicklime (CaO), 100
pounds; sulphur, 33$ pounds; water, enough to make 100 gallons.
Placed the lime and sulphur ina copper vessel, added 30 gallons of |
water, and boiled for two hours, then filtered. The solution was of a deep
orange-red color. After standing for a few minutes needle-like crystals

is)

somewhat resembling the down on the seeds of thistles separated out.
These were composed of bisulphide of lime (CaS,) and being freely solu-
ble in water, were dissolved when the balance of the water was added.
In this action all of the sulphur had been incorporated with the lime,
since the residue when dried would not ignite. Added a sufficient
quantity of water to the above solution and sprayed an apple tree with
it at 10:30 a. m. Mareh 18, sun shining, light breeze.

About 14 hours after making the above experiment it began to rain
very gently and this was continued for 24 hours. April 23, I found a
great many living San José scales on this tree. At the time of making
the above test I also sprayed some of the solution on a branch of a
peach tree in full blossom, but this did not appear to produce any in-
jurious effect upon the blossom, since at the time of my visit on the
23d of April this branch bore as many peaches as did any of those I
had not sprayed. It seems almost certain that the rain, coming on so
soon after the wash was applied, rendered neutral the effect of the
above solution on the scale insects sprayed with it. I have seen
orange trees that had been sprayed with the resin wash on a certain
day and a rain occurred during the night following the application ;
but the wash did not prove fatal to nearly as large a percentage of the
red scales as would have been the case had no rain occurred.

On the same day that the above test was made (March 18), [ also
tried the above mentioned lime and sulphur solution at half strength,
but it did not produce any apparent effect upon the San José scales
infesting the tree sprayed with it. It was now too late in the season
to make additional tests of this solution, but I hope to be able to fol-
low up this subject during the coming winter.

From the above experiments it would appear that neither lime, salt,
nor sulphur when used separately are effectual in destroying the San
José scale; and the same is true in regard to any two of them when
used in combination, except, perhaps, the lime and sulphur, which have
not as yet been sufficiently tested. It is very probable, however, that
these two ingredients give to the wash its insecticidal property, while
the addition of the slaked lime and salt simply impart stability to the
wash, rendering it less liable to be washed off the trees by the winter
rains. Should this surmise prove correct, then the directions given at
the head of this article for preparing this wash should be changed, an
equal number of pounds of lime being required with the 33 pounds of
sulphur, instead of only 21 pounds of lime, as at present used.

I experienced considerable difficulty in preparing and applying this
wash, owing to the fact that some of the materials used are not solu-
ble in water, necessitating an almost constant stirring of the solution
while it is being sprayed upon the trees. On this account it is quite im-
possible to spray it uniformly upon all of the trees, aud this difficulty
has also been experienced by each of our fruit-growers who have used 16
‘and with whom [ have conversed upon the subject, or who have written.

25910—Bull. 23 3

34

to me in regard to it. Some of the trees sprayed by this solution
would be very much whitened, as if whitewashed, whereas other trees
sprayed from the same tank as these would be scarcely discolored by
the wash. Itis, of course, the slaked lime added to the solution that
causes it to give the trees the appearance of having been whitewashed,
since neither the salt nor the sulphur discolor the tree to any appreci-
able extent, and the same is true of the bisulphite of lime, which is pro-
duced by boiling the quicklime and sulphur together.

The cost of 100 gallons of this wash according to prices furnished me
by Howell & Craig, wholesale grocers, of this city, for the sulphur and
salt, and by the Southern California Lumber Company, also of this
city, for the lime, is as follows, the materials being purchased in large
quantities :

Sulphur, 33 pounds; ati2, cents per pound 4.----- 45 22 eee $0. 70
Hime; 42 pounds, 2t4 of a cent per pounds sess -s-2 ee soe eee .oo
palts25 pounds abo, Obes Center POUNG ens eae === ae eee malt

Potalicos ..tsecse.cs sce ee tec ce oe ae eee rare eee $1.14

The salt quoted aboveisapoor grade, such as is used for salting hides,
and the price quoted is by the ton; the sulphur is in sacks, and the
lime in barrels containing about 220 pounds each.

Of the two washes above described—the resin, caustic soda, and fish
oil, and the lime, salt, and sulphur washes—the one containing resin is
greatly to be preferred. Not only is this wash easier to prepare than
the other, but it is also much easier to apply it to the trees, since it is
perfectly soluble in water and therefore does not require to be stirred
while being sprayed upon the trees. For this reason more uniform re-
sults will be obtained by its use than would be obtained by using the
sulphur wash. Moreover, the resin wash, by being properly diluted,
can also beused in the summer season, and thus only one wash need be
used at any time of the year. In my own experiments better results
were obtained by the use of the resin wash than were produced by the
sulphur wash. The price per gallon of each of these washes is about
the same. The sulphur wash should never be used on trees in leaf nor
on those just starting to leaf out, and this is also true of the resin wash
when made according to the formula given in the preceding article.

MISCELLANEOUS EXPERIMENTS.

CORROSIVE SUBLIMATE (also known as mercuric chloride, HgCl,).—
Some time ago one of the Horticultural Commissioners of San Ber-
nardino County remarked to me that he had used a simple solution of
corrosive sublimate for the purpose of destroying various kinds of seale
insects on nursery trees, and had obtained very good results by the
use of the same; and it was also reported in some of the San Diego
papers that a gentleman living in that county had obtained better re-
sults by the use of a solution of the above kind than he had by using
any other kind of insecticide for the destruction of the black scale.

- fay ha eal tote oa

a males *y

—— Se Se Se ie

35

Thinking the subject worthy of investigation, I made a few experi-
ments with this substance, but the results were far from being satis-
factory. I dissolved the sublimate in cold water by frequent stirring ;
this required abeut 15 minutes, and the solution was of a dark bluish-
gray color. Following is a brief account of these experiments:

(224) Corrosive sublimate, 24 ounces; water 100 gallons. Sprayed
on an orange tree infested with the red scale at 3 p. m., October 10, sun
shining, light breeze. November 13, leaves and fruit uninjured; found
great many living red scales on this tree.

(223) Corrosive sublimate, 44 ounces; water, 100 gallons. Sprayed
on an orange tree at 2:30 p. m., Octeber 10, sun shining, light breeze.
November 13, leaves and fruit uninjured; found great many living red
scales on this tree.

(236) Corrosive sublimate, 1; pounds; water, 100 gallons. Sprayed
on a dormant pear tree infested with the San José scale at 10 a. m.,
December 31, sun shining, light breeze. February 3, found a great
many living San José scales on this tree.

The price in this city of the corrosive sublimate in 10-pound lots is
at the rate of $1.40 per pound; at this rate the strongest solution I
used (experiment 236) would cost about $1.63 per 100 gallons. I did
not test a stronger solution than this, since its cost alone would prevent
its being extensively used.

GLUE.—For the purpose of testing this substance as an insecticide
for the destruction of the red scale on citrus trees I made a few experi-
ments with it, but with very unsatisfactory results. The grade I used
is of a light brown color, not the white, nor yet the poorest grade, but
such as is used by cabinet-makers. ‘To dissolve the glue I simply boiled
it in water, and it dissolved in about 10 minutes. Lollowing is a brief
account of these experiments:

(227) Glue, 45 pounds; water 100 gallons. Sprayed on an orange
tree infested with the red scale at 4:30 p. m., October 11, sun shining,
light breeze. November 13, leaves and fruit uninjured; found great
many living red scales on this tree.

(226) Glue, 8.1 pounds; water 100 gallons. Sprayed on an orange ©
tree at 4p. m., October 11, sun shining, light breeze. November 13,
leaves and fruit uninjured; found great many living red scales on this
tree.

(225) Glue 124 pounds; water 100 gallons. Sprayed on an orange
tree at 3:30 p. m., October 11, sun shining, light breeze. November 13,
leaves and fruit uninjured; found great many living red scales on this
tree.

In this city (Los Angeles) the price of glue of the above grade in 10-
pound lots is at the rate of 50 cents perpound; at this rate the strongest
solution I used (experiment 225) will cost $6.25 per 100 gallons. This,
of course, is much too expensive for ordinary use as an insecticide, and
for this reason I did not test a stronger solution.

36

ALoEs.—Dr. M. F. Bishop, of Alameda, the owner of a large orchard
of deciduous fruit trees in the vicinity of San José, in the northern

part of the State, gave me a package of aloes, with the request to test.

it on the scale insects infesting citrus trees. Accordingly I made a
few tests with it, simply dissolving the aloes in cold water, straining
the solution through a piece of Swiss muslin, and then spraying it
upon the tree. The aloes is not readily soluble in cold water, and 4
days were required for it to dissolve, being occasionally stirred during
this time. The experiments are as follows:

(243) Aloes, 124 pounds; water, 100 gallons. Sprayed on an orange
tree infested with the yellow scale (Aspidiotus citrinus) at 10:30 a. m.,
March 22, sun shining, light breeze. April 23, leaves and fruit unin-
jured; found many living yellow scales on this tree.

(242) Aloes, 25 pounds; water, 100 gallons. Sprayed on an orange
tree at 10 a. m., March 22, sun shining, light breeze. April 23, ieaves
and fruit uninjured; found several living yellow scales both on the
leaves and {fruit of this tree.

The price of the aloes in large quantities is at the rate of 16 cents
per pound; at this rate the strongest solution I used (experiment 242)
would cost $4 per 100 gallons. At this strength (25 pounds of aloes to
100 gallons water) it proved fatal to a large percentage of the scale
insects, and doubtless if it had been used one-half stronger it would
have been entirely effectual; but the high price of a solution of the
latter strength would prevent its being used on a large scale.

Te Oe

REPORT OF EXPERIMENTS WITH RESIN COMPOUNDS ON
PHYLLOXERA, AND GENERAL NOTES ON CALIFORNIA
INSECTS.

By ALBERT KOEBELE.

LETTER OF SUBMITTAL.

ALAMEDA, CAL., October 20, 1890.
Str: J herewith submit report upon experiments, chiefly with resin compounds, on
Phy'‘loxera vastatrix, and observations made during the year.
Very respectfully,
ALBERT KOEBELE,
Field Agent.
ron. C. Vi. RILEY,
U. S. Entomologist.

By your direction a series of experiments was carried on, chiefly with
resin compounds, upon the Phylloxera in Sonoma Valley during Septem-
ber and the beginning of October.

In preparing the compounds the following were used: Bicarbonate
of soda, sal soda, and Greenbank’s caustic soda, 98 per cent. ‘Three
pounds are required of the former to dissolve 4 pounds of resin prop-
erly, or, in other words, to make a resin soap; 1 pound of the latter is
sufficient. to dissolve 10 pounds of resin or even 11, but I did not suc-
ceed in dissolving 12 pounds, as parts of the resin would always re-
main. In repeated and careful trials this could not be overcome.

The results showed somewhat in favor of the bicarbonate of soda as
far as to destruction of the insects, but the price has to be considered.
Next to this seems to be the emulsion prepared with caustic soda, but
it is a difficult matter to decide which will work best without carrying
on an extensive series of trials. It is safe to say, however, that the
results will not vary greatly.

One pound of resin was used to each 10 pints of compound, and
this again was diluted with water at a strength of 1 pound of resin in
24 gallons of water, up to 1 pound in 37§ gallons of water—one part of
compound in thirty parts of water. This compound will, as has been
previously stated, do effective work on unprotected Aphids, 2. e., such

as are not covered with cottony or mealy exudations, at one part in
37

38

fifteen parts of water, or 1 pound of resin in about 16 gallons of water.
(The former mixtures were somewhat stronger; 1 pound of resin in
9 pints of liquid.) The action upon the Phylloxera is much more
marked and with a mixture of one part of compound in thirty parts of
water the insects, if immersed for a few seconds only and left exposed,
will die, notwithstanding this solution will not adhere to parts of the
roots, not having at this strength the required penetrating power which
a sufficiently strong solution, say about 1 pound resin in 15 gallons of
water, has, and more so than any other insecticide I know of. The
experiments were made on 25-year-old Tokay vines (the only ones re-
maining that have withstood the ravages of the Phylloxera), in loamy
soil, which was completely dry and hard at this time of the year, no
moisture being noticeable until a depth of from 10 to 12 inches below
the surface was reached. '

In all cases the ground was removed to a depth of about 6 inches,
forming a hole 4 feet in diameter. Ten gallons of the solution, it was
observed, penetrated here to 12 inches in depth around the roots where
the hole was deepest, or about 18 inches from original surface of ground,
and most of the insects were destroyed to about 16 inches in depth, if
the 10 gallons contained 4 pints of compound. In the later experiments
these holes were made only about 2 feet in diameter, and nearly if not
the same results were obtained with only half the amount or 5 gallons
of the mixture. This is more practical, as the chief roots only are
reached and the solution can be used so much stronger. The less
solution required the better, providing it will do the work, for at 10 gal-
lons to each plant this would mean 7,000 gallons or over per acre. If
the solution is applied at another time of the year, say early spring,
when rain is still expected, the results undoubtedly will be still more
favorable. I have had excellent results with solutions prepared with
caustic soda by using 4 pints of this to 16 pints of water only and ap-
plying 5 gallons of water soon after and 5 gallons the following day.
This destroyed the Phylloxera to nearly the depth the fluid reached.
Thus it wili be seen if a small amount of the mixture, sufficiently strong,
be applied in early spring the following rains will do the rest. As it
was, with the dry soil, the 4 pints of compound in 10 gallons of diluent
did better work than the same amount of compound in only 5 gallons,
for the simple reason that it penetrated farther and thus reached more
of the insects in sufficient strength to kill. It must also be remembered
that a completely dry soil will take up a large amount of the 1 quid,
whereas in a moist soil this is not the case.

The compounds were prepared as formerly, sal soda 3 pounds, resin 4
pounds, dissolved together with 1 quart of water, and water added
slowly while boiling to make 40 pints. The caustic soda, which comes
in 10-pound tin cans, is dissolved in 4 gallons of water, after which 4
gallons more should be added. This lye will dissolve 100 pounds of
resin and make 125 gallons of compound, sufficient for 250 plants, and

39

costing at wholesale in San Francisco (T. W. Jackson & Co., No. 104
Market street) $2.50. This is sufficiently strong, and to use more is
unnecessary, as it was found that even 3 pints of the emulsion to the
plant would do the work.

_I will give here a receipt for preparing the cheapest compound. This
is with common caustic soda, such as is sold at wholesale at about 5
cents per pound: |

EC austicisoda,auapelicenue seme selene nec elen acide sen) Soe ee pounds.. 5
COS IMete o's ote ie sieves als ota eT Toei ale es alajale or see cielo cic! icles baile ce do 40
Wiaterstoumakes ss.) 25s totes sean (he ore ira cis aoe 1eSs\4) Selete gallons.. 50

First the soda should be dissolved over fire with 4 gallons of water,
then the resin added and dissolved properly, after which the required
water can be given slowly while boiling to make the 50 gallons of com-
‘pound. This will make 500 gallons of the diluent, sufficient for 100
plants, and costing about 84 cents. ;

While a much weaker solution would kill the Phylloxera, this is
recommended, as it also destroys their eggs effectively. Below are
given the results of some of the experiments to show the effects of
various strengths. Most of these have been duplicated or tried upon
several plants. A small mite (Tyroglyphus sp.), always very abundant
among the Phylloxera, and, as a rule, feeding upon the sap of the
roots, yet from numerous empty skins appearing to feed also upon the
lice, was in no case injured by these resin washes. °

ComPpouNnD No. 1.— Bicarbonate of soda, 3 pounds ; resin, 4 pounds, and
water to make 40 pints, costing 15 cents.

Compound, 1 gallon; water, 6 gallons; in holes 4 feet in diameter.
Destroyed insects to about 12 inches in depth from original surface, as
well as the eggs of the same, which became dark in color.

Compound, one-half gallon; water, 4 gallons. Destroyed all insects
where they were reached (occasionally a living one running about).

Compound, 1 part; water, 10 parts; about 10 gallons of the fluid
used. This will destroy all lice and their eggs completely to 12 inches
from original surface, but not deeper.

Compound, 1 part; water, 12 parts; 93 gallons used. Twenty-four
hours after application some of the solution remained still on tep, and
on examining 6 days later it was found that it had penetrated the ground
to 12 inches from original surface. Much of the solution had evap.
orated and left a brown scum (dry soap) on top. It will also destroy
most, if not all, of the eggs.

Compound, 1 part; water, 14 parts. Three and three-fourths gallons
of the diluent in holes 2 feet in diameter killed the insects to 8 inches
in depth, or 14 inches from original surface.

Compound, 1 part; water, 16 parts; 8$ gallons diluent. Occasion-
ally a living insect found and large numbers of mites on the nearly
dead vines.

40

Compound, 1 part; water, 18 parts; 93 gallons diluent; examined 5
daysafter. Nearly alltheinsects dead to 14 inches in depth, but most of
the eggs looked bright yellow and no doubt will hatch. Behind the
thick bark near the top, where apparently the solution did not penetrate,
a number of young lice were found alive.

Gompound, 1 part; water, 20 parts; 105 gallons diluent; in holes
4 feet in diameter. An examination 5 days later showed the fluid
had penetrated the ground on plants 153 or 20 inches from original
surface. All the insects were destroyed 13 inches in depth and but
very few living 3 inches deeper. This solution seems to work best of all
this series, but it is doubtful if the eggs will be affected by it.

CoMPOUND No. 2.—Caustic soda, 98 per cent., 1 pound ; resin, 10 pounds ;
water to make 124 gallons ; compound costing 25 cents.

Compound, 4 pints; water, 4 pints; in hole 4 feet in diameter; 5
gallons of water added 1 hour later and the same quantity next day.
Very few dead insects were found upon this plant, and none living.
Not sufficient to show proper result.

Compound, 4 pints; water, 2 gallons; 5 gallons of water added 1 hour
after and 5 gallons the following day. Examined plants 7 days later ;
result very satisfactory, hardly any living phylloxera as far as the fluid
reached. After examination 5 gallons more water were added and
again examined a week later, when no living insects could be found to
a depth of 18 inches.

Compound, 4 pints; water, 10 gallons. Destroyed insects to about 8
inches in depth and but few below this.

Holes only 2 fest in diameter; 5 gallons of water in same first, and
solution 1 hour later in the four succeeding experiments.

Compound, 4 pints; water, 45 gallons; examined 15 days later. De-
stroyed insects and eggs as well, which had become very dark. Occa-
sionally a live specimen running about.

Compound, 3 pints; water, 44 gallons. Examined 13 days later and
found all insects dead that had been reached.

Compound, 24 pints; water, 373 pints. Examined 13 days later. A
piece of root about 10 inches deep one-halfineh in diameter by 6 inches
long and completely covered with phylloxera showed but one single
living young, probably hatched from egg after application.

Compound, 2 pints; water, 43 gallons; also examined at the end of
13 days. All insects to § inches below ground or 14 inches below orig-
inal surface were destroyed, as well as a large part of the eggs. Oc-
casionally a living young was found wandering about.

Four other experiments were made with this compound, using 1, 2, 3,
and 4 pints in 20 of the solution, the ground having 4 hours previously

been saturated with 5 gallons of water in each case. Examined 12 days ©

after; results were not good with 1 pint but were progressively better
with the other three. Applied 4 gallons more water on plants where 3

Al

and 4 pints had been used, and found 2 days later that this additional
water still increased the effect.

In addition to this a number of plants were treated with this compound
to note the results next spring. The holes were made 2 feet in diameter,
and after the solution had disappeared fhe wet ground from the outside
was placed around the plant and the hole closed again. The experi-
ments were: Five piuts of compound in 5 gallons of the solution, four
plants; 4 pints of compound in 5 gallons of the solution, eight plants ;
3 pints of compound in 5 gallons of the solution, ten plants; and 2 pints
of compound in 5 gallons of the solution, ten plants.

CoMPOUND No. 3.—Caustic soda, 98 per cent, 1 pound ; resin, 8 pounds ;
and water to make 10 gallons of compound, costing 22 cents.

Compound, 4 pints; water, 74 gallons. IHixamined 6 days later; result
good. 3

Compound, 4 pints; water, 10 gallons. Examined 6 days later and
found result favorable.

Compound, 3 pints; water, 75 pints. Found only part of insects de-
stroyed 6 days later.

Compound, 3 pints; water, 90 pints. There were not enough insects
upon this plant to deduce fair results, which would no doubt be very
poor.

CompounD No. 4.—Sal soda, 3 pounds; resin, 4 pounds ; and water to
make 5 gallons of compound ; costing 11 cents.

Compound, 4 pints; water, 74 gallons. Iixamined 5 days later and
found all insects killed except a few living on a plant under thick bark,
where solution apparently did not penetrate.

Compound, 4 pints; water, 10 gallons. Examined 5 days later and
found insects dead to 12 inches in depth from original surface, with only
occasionally a live one walking about.

Compound, 3 pints; water, 75 pints. On examining, 5 days later,
only the insects near surface were found dead.

Compound, 4 pints; water, 15 gallons. This destroyed only partly —
the lice near the top.

The following four experiments were made with this compound, the
ground having been previously soaked with 4 gallons of water:

Compound, 3 pints; water, 21 pints. Examined 12 days later. Did
not show good results, as part of the insects were found alive. ‘Twice
the amount of water with the same quantity of compound will do much
better work.

Compound, 3 pints; water, 33 pints. Examined 12 days later and
found results fairly good. Only a few living ones were running about.

Compound, 2 pints; water, 30 pints. On examination numerous live
insects were found, but more than half were killed.

42

Compound, 2 pints; water 38 pints. Result about the same as in
preceding experiment.

These four experiments were repeated and the water added (3 gal-
lons) 2 hours after instead of before application of emulsion. The re-
sults in this case were much more satisfactory, destroying most of the
eggs in the two first experiments and nearly all of the phylloxera in the
two last to a depth of about 10 inches. 7 :

GENERAL NOTES.

It was probably owing to the unusually heavy rainfall during last
winter that insects were comparatively scarce in the early part of the
season. At least no complaint was noticed or heard during this time.
While a large number would undoubtedly be destroyed by weeks of
excessive rains and floods, yet there are such as are not or only slightly
affected by this element. I may cite here, for instance, such species the
~ eggs of which are found upon trees and shrubs during the winter months
as well as the eggs of locusts usually deposited on dry hillsides. Ona
visit to Sonoma county during May, the larvee of Clisiocampa were ex-
tremely abundant. Two species were found, namely, C. constricta and
C. thoracica. The first species predominated in numbers, and while
usually feeding upon deciduous oaks was also found upon Live Oak and
Quercus agrifolia as well as various shrubs. In confinement these larvee
were furnished with food consisting of leaves of Plum and Cherry, but
for three days they would not feed upon these and readily attacked the
leaves of Live Oak which were given them, and upon these they were
raised. (C. thoracica, which is the species defoliating various fruit trees,
was found chiefly upon willows, but also upon oaks, and here again
usually upon White Oak, upon which its eggs were found in October.
This species was bred upon leaves of Prune and Cherry.

At the end of May of the present year, I received from Mr. F. L.
Washburn, entomologist of the experiment station at Corvallis, Ore-
gon, a few Clisiocampa larve new to me. He said they were found
feeding upon a species of Crataegus and were sent with leaves of apple,
upon which I reared them. On my visit to Washington these larvee
were met with at Tacoma, on June 8, within webs upon Alder (Alnus
rubra), and again at Easton, during July, upon Willow. Near Tacoma
I also found what I took to be the larve of C. thoracica very abundant
upon Crataegus, Alder, Hazel, and various other shrubs. Two of the
larve were taken to Kaston, and one pupated and to my surprise pro-
duced not the expected C. thoracica, but C. erosa Stretch.

About 10 miles along the railroad in southern Oregon, about the be-
ginning of June, larvxe and webs of one of these moths were seen in
large quantities on dry hillsides upon Purshia tridentata DC., Ceanothus
sp..and also Wild Cherry. While crossing the Columbia River on
steamer, June 8, at which time the water was very high, large numbers
of these larva were observed floating upon the swift current and as

43

many as a dozen could be seen at one time, but of all the hundreds seen

very few weredead. They were usually in a half circle and completely

dry above and were carried off to be distributed safely along the shores.
In both cases I had no opportunity to obtain specimens for identifica-
tion.

As to the parasites, so far two species of a small Chalcid were bred
from 37 egg masses of C. constricta found within three hours while col-
Jecting Cynipid galls in Sonoma County during October. This species
is preyed upon by Tachina flies, which are or have been, the present
season, the chief agent in destroying them. From about two hundred
grown larve collected but very few moths were obtained, the Tachina
maggots issuing from the dying and spun-up larve in large numbers.
No ground for their reception had been furnished in breeding cases and
they pupated among the leaves and excrement. Atleast 80 per cent
of these larve were parasitized and but one of the flies has issued up
to date. I also obtained one large cocoon of an Ichneumonid from
larvee in confinement and others were still found in nature during Sep-
tember.

C. thoracica was also infested by Tachina larve, but only about
30 per cent. were destroyed by these maggots. Two species of the flies
have come out so far. C. californica was noticed full of eggs of these
flies and some had previously been bred. An Ichneumonid was ob-
tained from young larve the present year. Professor Livers, of
Berkeley, informed me the end of April that he had previously ob-
served one of these larvee at Bay View upon Willow, and accordingly
a trip was made to that locality and this species was found as well as
its tents, not alone upon Willow, but also on the scrubby Live Oaks
growing there, Hazel, Wild Currant, Rhamnus californica, Blackberry,
and other plants, showing that this species is not confined to Live Oak
alone.

No Tachina has yet been obtained from the species in Santa Cruz
Mountains, nor have I observed any eggs, but larve of this species
placed upon Cherry and Prune at Alameda were badly attacked. The
same species of Ichneumonid bred from larvee of C. californica has also
been obtained from this. This species was observed upon Plum, Prune,
Willow, Ceanothus and Cercocarpus.

Two species of Ichneumonids were bred from the new species of the
north, one from larve found at Tacoma, and the second from those
found at Easton.

I may mention one Noctuid larva as very destructive to buds, young
fruit, and foliage of fruit trees, chiefly Apple, Pear, Plum, and Prune.
This is Teniocampa, and I have full proof that the destruction of a
large share of the buds and young fruit, so universally, yet incorrectly,
attributed to birds on this coast, is due to this larve. In the very
early spring, often in February, these moths make their appearance
from hibernated chrysalids and copulate, and the female deposits her

44

eggs, from two to three hundred or more, in crevices of bark. I found
them in large numbers together, thrust deep into a place whiere one of
the branches had broken off. The young larve soon made their ap-
pearance and in want of leaves began to feed upon buds and blossoms,
and later on, as I have repeatedly observed on apple trees, upon the
young fruit also. Within about 24 days these larve become full grown
and enter the ground for pupation to remain in this state for nearly 11
months. If only one or two early broods occur upon a single or-
dinary tree, they will, in some cases, destroy most if not all the fruit
buds before any leaves appear. The light green, white, variegated, and
Striped larve at rest on the under side of leaves during the daytime
are not, especially by an untrained eye, very readily discovered, and
hence are overlooked and the more innocent bird is made responsible
for the damage done.

During April, 1888, when I had a brood of these larvez in confine.
ment at Alameda, a common titmouse, Lophophanes inornatus Gamb.,
was noticed flying constantly to an old apple tree and carrying off
dozens of these very larve to a hollow tree not far distant, within
which it had a nest with six young. These birds are quite plentiful
at this time of the year and are the only enemy of this larva as yet
observed. None of the numerous larve collected the present year
appear to be parasitized. 3

By jarring the trees in the early morning these larve, especially the
larger, will fallto the ground, and can readily be collected and destroyed.
If the tree be only slightly shaken, all the mature larve will drop.

Caloptenus devastator, so well remembered since its outbreak in 1885,
has again been on the increase the present season and is quite abun-
dant in Sonoma County as well as around Alameda, where Camnula pel-
lucida was equally as numerous. Aside from complaints in Sonoma
County others were heard of in Yolo County. I quote from the Wood-
land Democrat of September 11, 1890:

For the past few weeks our farmers have been watching their alfalfa crops very
closely. The Army Worm and the Grasshopper are both here, although not in such
quantities as in the early days. In some cases the crops in young vineyards have
been entirely destroyed by them. C. Eakle lost all his grapes by the grasshoppers
and others have shared a like fate. In other cases the alfalfa crops have fared badly
from the eftects of the worm and the hopper. Mrs. P. Hannum had saved some alfalfa
for seed, but the worm attacked it, and she was obliged to cut it for hay in order to
save any of it. Mr. Hopkins, we understand, was caught in the same predicament,
while the pastures of those who have lately irrigated and where the clover is just
beginning to grow nice and green are full of the hoppers, and the worms have also
attacked many others.

As yet no specimens from the above locality can be obtained, but it
is more than likely that the injury was caused by several species and
the Devastating Locust among them. One favorable season, however,
should no parasites appear, would again show a marked increase in
destructive numbers, and local outbreaks may be expected the coming
summer.

ENTOMOLOGICAL NOTES FOR THE SEASON OF 1890.

By Mary E. MURTFELDT.

LETTER OF SUBMITTAL,

KIRKWOOD, St. Louis County, Mo.,
October 31, 1890.
Str: Inclosed please find summary of my notes on injurious insects for the present
year, as observed throughout the season in St. Louis County, and as compiled from cor-
respondence with and occasional visits to other sections of the State. As in preced-
ing years, many thanks are due you for various determinations and helpful sugges-
tions.
Respectfully, yours,
Mary E. MuRTFELDT,
Prof. C. V. RILEY,
U. S. Entomologist.

GENERAL OBSERVATIONS.

The season of 1890 throughout the Mississippi Valley has been in
many respects unusual. The winter months were characterized by a
temperature much above the normal, by occasional very heavy rains,
and, after the middle of January, by a prevalence of clouds and exces-
sive moisture. Many shrubs, for example Forsythia, Cydonia, and
Lilac bloomed in the open air about the holidays, while the buds of all
fruit trees were much swollen, and peaches and apricots opened their
blossoms in sheltered situations in February. During early March the
mercury for the first time in the year dropped to the neighborhvood of
zero, and on the last day of the month occurred a phenomenal fall of
snow. April also was cold and damp, and similar weather prevailed
until the middle of May, the soil, except where drainage was excep-
tionally good, being in poor condition for planting. With the first of
June excessive heat set in, and for seven consecutive weeks the mercury
was seldom below 90° F. at midday, and usually approached or ex-
ceeded 100°... This extreme heat was accompanied by an equally severe
drought for the same length of time, scarcely mitigated by two or three
very slight and very local showers.

45

46

That the effects of such a season should be plainly marked on insect
life is not surprising. The following memoranda show considerable
deviation from the records of preceding years. ~

Chinch Bugs were not reported as injurious in any part of the State,
and scarcely a specimen could be found during midsummer and early
autumn.

Canker Worms.—Very few, and found mostly in orchards or on trees
standing somewhat albove the general level. The male moths were fly-
ing every month duzing winter, and an occasional female was also seen
in January and February. Probably the severe cold of March destroyed
a large proportion of the very young larvee, more perhaps by retarding
the development of the apple leaves than by the direct effects of the
cold.

Of the few worms that were found later in the season taking their
noonday siesta on the trunks and larger branches of the trees, quite a
number were seen which had evidently been attacked by some Carabid
or other predaceous species, the skin having been punctured and the
fluids oozing out with every motion. All injured worms perished, but
what the assailant was I was not able to discover.

Cutworms (Agrotis and Hadena).—Vegetable gardens in the spring
enjoyed an immunity from these pests that was most welcome to the
gardener. This was probably due to the fact that some of the most
destructive species hibernate in the larva state, and the degree of cold
not being sufficient to reduce them to complete dormancy they perished
of starvation and dampness or fell victims to the birds, which remained
with us in greater numbers than is usually the case. My memoranda
show that very few Noctuid moths of any kind were taken at light
previous to the middle of August. To this scarcity of Noctuid pests
there were, however, two notable exceptions—that of Gortyna nitela and
Heliothis armigera, which have seldom committed so great injuries to
certain crops as during the present year. About the middle of June
many samples of young corn and potato stalks were sent me that were
being bored by the first-named larva, and it was then reported from
some localities—among others from Kidder, Missouri—as having de-
stroyed fully one-half the crop of potatoes. Its injuries to young corn
were also extensive, but I have no data for making an estimate. It was
also found in considerable numbers, when very small, in small grain.
In this it could scarcely reach maturity, and probably migrated to the
stalks of such more succulent plants as were conveniently near. Inthe
case of the attack on potatoes a treatment with Paris green and flour
was recommended, on the probability that in passing from one stalk to
another the worm would obtain a sufficient quantity of the poison to
destroy it. Of the success of this experiment, if tried, I have not been
informed. It did not occur in any noticeable numbers in the vicinity
of Kirkwood.

Heliothis armigera was very destructive on both early and late corn,

AQ

especially on the latter. In the southern part of the State it injured
the tomato crop to a considerable extent. Spraying with Paris green

and with other arsenical compounds was tried with considerable success

previous to the ripening of the fruit, but there is considerable danger

in its use and it is best to thoroughly drench the plants that have been

treated with clear water a day or two after the use of the insecticide.

Experiment on a limited scale shows that it can be kept from corn by

the same remedies, but how far this would be practicable in the field

has not yet been demonstrated.

The Striped Flea-bectles (Phyllotreta vittata and P. sinuata) did not ap-
pear at all on early Crucifers, nor have they been observed in any con-
siderable numbers in this vicinity at any time during the growing sea-
son. Whether this notable riddance was due to atmospheric conditions
or to the scarcity of the fostering weeds, Lepidiwm and Arabis, I am not
able to decide.

The Corn Flea-beetle (Chetocnema pulicaria) was reported to me from
various localities as unusually numerous and injurious. Mr. Falcon, of
St. Clair County, feared that he should lose his first planting from its
attacks, but from later accounts the plants recovered more rapidly
than he had expected.

The Plum Curculio was much reduced in numbers during winter, and
as there was in this section, and indeed throughout the State, an almost
entire failure of stone fruit crops, with the exception of the sour cher-
ries, which the insect rarely attacks, there was very little of the work
of the latter observed. A small proportion of the few early peaches
that set were punctured, but that the midsummer drought prevented
the development of the larvz was indicated by the fact that such late
peaches as there were did not show a single one of the food punctures
which commonly so disfigure them. On one tree which the previous
year had suffered so much in this way that the fruit was absolutely
worthless, was a single peach that reached perfection without one
stroke from the beak of a curculio; and similar observations were
made on other trees on which a very little fruit ripened. Nor was I
able to find Conotrachelus breeding in apples, although during June
and July I examined nearly six hundred specimens of fruit, a few of
which showed punctures that might have been made for food. Should
other conditions be favorable, I think, so far as this insect is concerned,
we may predict for 1891 fine crops of stone fruits.

Plant lice, always quite abundant in the spring, amounted this year
almost to a scourge. ‘Trees, shrubs, and herbs alike suffered, and for
many plants there was no after-recovery. The species causing the most
appreciable loss was probably the Grain Aphis (Siphonophora avene). It
occurred throughcut the State on all small grain, even on rye, causing,
undoubtedly, some shrinkage of that crop as well as of wheat, but its
most disastrous attacks were on oats. About the middle of May farm-
ers began to be alarmed for the safety of this crop, and subsequent

48

developments proved their fears to be well grounded. Letters of
inquiry and packages of specimens came to me from all directions, and
during a trip about the first of June, to Butler County, on the southern
boundary of the State, I was able to observe for myself the dwarfed
and sickly appearance of small grain everywhere along the railroad,
attributable in all cases to the attacks of this insect. Shortly after-
ward the outfields in St. Louis County and in many other localities
were plowed up and replanted to corn, which, owing to the drought and
to its own insect enemies, was, in its turn, a poor crop. The unusual
prevalenceand unparalleled multiplication of Aphidide was undoubtedly
due to to the scarcity of their natural enemies, both parasitic and pre-
daceous. It was not until the middle of June that the larve of Syrphv.
de, Coccinellide, and Chrysopa became numerous, and, reénforced by
parasites of the genera Aphidius and Trioxys, finally brought relief from
the pests; too late, however, to prevent irreparable injury to many
herbaceous crops, young fruit trees, and various sorts of shrubbery.

A somewhat remarkable development of the season was the appear-
ance in unusual numbers of many insects not often accounted noxious,
and the reappearance of some species not observed in this locality for
many years. |

Among the former may be mentioned the great abundance and variety
of “stinging” larve, principally Limacodes. For the first time in my
experience the beautiful larve of Parasa chloris were so abundant on
some young apricot trees in the orchard of one of our neighbors as to
do great damage to the foliage. When full grown, three-fourths or
more of an inch in length, thick, oblong, sub-cylindrical, gaily striped
longitudinally in carmine red, purple, and bright yellow, the stinging
spines concealed in the two rows of deflected bright yellow plumes that
adorn the back, gliding with slow, graceful motion over the leaves, they
were almost too ornamental to doom to destruction. As they were
very voracious, however, the latter was a necessity of the case. Those
that were preserved were fed to maturity on the leaves of Chickasaw
plum, to which they were transferred without difficulty.

ERuclea querceti H.8., of the same form and size as P. chloris, but much
less brilliantly colored, being of a dull, mottled green, with two or four
dark purple-red spots on each side of the dorsum, and having the plu-
mose spines pale green, appeared on Plum, Cherry, and Apple in the
orchard, as well as on Sycamore, Post Oak, and Wild Cherry in the
forest. It was not, however, in any destructive numbers on any fruit
tree.

So far as coloration is concerned this larva varies greatly. The crim-
son sub-dorsal spots, usually quite large when there are but two, are
in some examples smaller and less couspicuous and are followed pos-
teriorly by a second pair. The longitudinal ridges on which these are
situated, and from which also proceed the larger urticating spines,
vary in hue from pale pea green to yellow and bright orange. A second

‘

49

variety was so distinct as to be described, previous to breeding, as
another species. This is entirely of a pearly, translucent white color,

with fine, wavy, purple lines, one on each side cf medio-dorsal space
and two others lower down on each side inclosing the second row of
spines, which, like the general surface, are translucent white. There is
a large purple spot a little back of the middle on each side of the dor-
sum. I have found this variety only on pear, and it is rather rare.
The cocoon is spun among the leaves and does not differ in color, form,
or texture from those of other Limacodes. The moth bred from this
pale larva does not differ from those of typical querceti, being of a rich
fustic brown, with bright green and velvety black ornamentation. In
the size of the green and black spots and in general intensity of color
a series of moths of this species also exhibit considerable variation.

The almost equally beautiful and even more strikingly marked Saddle-
back Caterpillar (Hmpretia stimulea) occurred in very unusual numbers
on Plum, Pear, Chestnut, Maple, and Wisteria vine, doing considerable
damage—especially during the semi-gregarious period, which continues
to the third molt—to the foliage of the fruit trees attacked.

Phobetron pithecitum and Limacodes scapha were other species of this
group observed.

Lagoa crispata was quite numerous on White Oak and Chestnut, and
colonies of Saturnia io appeared on Corn and Sassafras and defoliated
several rose bushes in our garden before we discovered the authors of
the mischief. Altogether there was quite an array of ‘ urticators,”
and gloves were very necessary to preserve the hands of the collector
in taking them and also in caring for them in the rearing cage. They
seem to dispense stinging points all over the foliage over which they
crawl and all about the cage in which they are confined. I have often
had my hands smart for hours after changing the leaves and cleaning
the cage in which these larve had been reared, long after they were
inclosed in their cocoons.

There was throughout this nude contiguous States a notable outbreak
of Datana both D. angusti and D. ministra, but especially the former.
This species appeared on the Walnut in June, and the second brood
again in August, and from the excessive and repeated defoliations it is
probable that many fine trees have been destroyed.

During a journey taken about the 1st of September, numbers of
trees were noticed bearing what would have been a heavy crop of nuts,
but absolutely leafless, while the trunks were almost covered with larval
exuvie. The nuts were, of course, small and imperfect, the shrunken
husks clinging to the seed. Several collections of the walnut-feeding
larve were sent me, but not having a supply of walnut leaves conven-
ient, I was not able to rear any of them, as they refused to accept asa
substitute the leaves of hickory or of Rhus glabra or copalina, although
some years ago I bred them from the latter.

During September the black-necked larve of what I suppose will

25910—Bull. 23——4

50

prove to be D. ministra, Drury, appeared on post oaks in Kirkwood
and vicinity, defoliating portions of the trees infested. From their gre-
garious habit and their susceptibility to poison they were easily routed.
Even a stream of water turned upon them from the spraying pump
would dislodge and bring them to the ground, where they were easily
killed.

Orgyia leucostigma, a species formerly abundant in this locality, but
which I had not observed for ten or twelve years, was found on Sycamore
(Platanus), on which, strange to say, it would not feed after the second
molt, and consequently all caterpillars left on the tree perished before
attaining half their growth. The question suggested by this observa-
tion was how the young larve came to be upon this tree which so evi-
dently did not suit them for food. Icould not find either cocoon or egg
mass of the mother insect, nor were any of the larve discovered in
the adjacent orchard.

Ichthyura inclusa, another species not observed here for many years,
appeared on willows in great numbers in September, but coming so late
in the season the defoliations did no serious damage.

In concluding these notes [ wish to mention an insect that will prob-
ably prove most efficient in ridding the country of the pest of the Web
Worm (Hyphantria cunea). This is the larva of a small and inconspicu-
ous Carabid of the genus Plochionus, bearing the appropriate specific
name timidus. I had observed during the month of June that the
greater number of the webs of the caterpillar were unusually small and
incomplete and seemed to have been deserted much sooner than usual.

Before I had time to investigate the matter, I received from Mr. J. C.
Duttey, horticulturist at the Shaw Botanical Garden, a colony of the
worms, interspersed among which were numerous small active Carabid
larve, which Mr. Duffey informed me were preying upon the former.
The collection was placed in a cage and arranged for convenient obser-
vation, and I very shortly had ocular demonstration of the correctness
of Mr. Duttey’s assertion. Many interesting observations were made
upon these small but ferocious larve before they changed to pup, and
the appearance of the perfect insect was awaited with much interest.
The first beetle developed about the middle of July and proved to be
the species named.

Comparatively few webs of the second brood of Hyphantria were seen
in and around Kirkwood in August, and extensive examination revealed
the fact that fully three-fourths of these also contained larve of Plo-
chionus, which were busily engaged in reducing the numbers of the
rightful inhabitants. Nor is the beetle confined in its diet to the web
worm. I found the larve repeatedly during the present autumn in the
masses of leaves webbed together by the somewhat gregarious larve
of a Tortrix (Cacecia fervidana) and between the two leaves webbed by
various Tineids, especially Cryptolechia nubeculosa and C. schlegerella.
(I doubt not I may have occasion to deprecate its work in the future

51

in these groups.) That this Plochionus had not appeared this season
much to the east of St. Louis was evinced by the much webbed and de-
foliated orchard and forest trees noticed in Illinois and Indiana in Au-
gust and September.

As Mr. Duffey proposes scon to publish a liistory of the insect, with
detailed descriptions of its various stages, I defer offering my own notes
upon its habits and forms until after the appearance of his paper.

A FEW MORE INJURIOUS MICROS ON APPLE.

A very considerable number of Microlepidoptera, including Pyralide,
Phycitide, Tortricide, and Tineide, have already been characterized
and catalogued among the more or less injurious insects of the orchard
and garden; but the observations of almost every year add to this list,
and I propose here to briefly describe a few which have not as yet been
placed on the roll, but which in this locality are annually so numerous
as to commit appreciable injury.

PENTHINA CHIONOSEMA, Zell.—The larve of this beautiful species
were, last year, uncommonly abundant during the month of May on the
leaves of apple, particularly in young orchards. They fold the leaves
at the midrib, or sometimes one edge over to the midrib, fastening the
edges all around firmly and feeding upon the inclosed upper surface.

Larva.—The larva is not especially characteristic, being of a pale opaque green
color, without maculation, except the rather inconspicuous glassy piliferous plates.
Head pale yellow, tinged with green, legs similarly colored; length from 16 to 17™™;
diameter, 3™™, Form subcylindrical, tapering but slightly either way from middle.

When full grown it incloses itself under a rolled edge of the leaf,
lining and strengthening the tube thus formed with a white silken web.
The moth appears early in June, and I have no record of a later brood,
although there may be one.

The original description, by Professor Zeller, is not accessible to me
at present, but it will suffice to note the following characters:

Palpi and tuft of the head rich ferruginous, antennz scarcely half the length of
the wing, fine, gray brown. Thoracic tuft dark brown. Wing expanse from 15 to
16 ™™_yather more than a half-inch. Ground color of primaries somewhat mottled
dark brown, with a slight suffusion of olive, diversified by three broad, indistinct,
irregular, obliquely transverse bands of purplish gray, having a somewhat metallic
reflection; these transverse bands broaden toward the inner margin, where they
almost coalesce. On the costal edge is a large, milk-white, rounded triangular or
nearly semicircular patch, extending along the costa from the middle third, in-
clusive, almost to the apex, constituting a most distinguishing and ornamental
character. Cilia purplish gray. - Secondaries, silky, pale brown with lighter fringes.

Abdomen and legs pale brown. Under side of wings pale, rosy brown, the large
costal spots on this side inclining to orange.

PROTEOPTERYX SPOLIANA Clem.—The larva folds and webs into
clusters the young leaves of apple during the month of May, appear-
ing, preferably, on the shoots of small trees.

52

Larva.—When full grown it measures 10™™ in length by 24™™ in diameter, the
form being rather thick cylindrical; color translucent white, tinged with yellowish
green; surface velvety; piliferous plates small, glassy, giving rise to short, fine,
light hairs. Head and cervical collar same color as general surface or a little deeper
in shade, inclining to amber. The head is broad and flat, with red-brown trophi,
and a very large dark brown spot on each side. Legs and prolegs same color as gen-
eral surface.

When full grown it forms a tough, oval cocoon, thickly covered with
particies of soil, on the surface of the ground, occasionally just beneath
it. It is but single-brooded, and is very difficult to rear in confinement,
as it must be kept through the heat of summer and the cold of winter,
and if a little too damp it molds, while if moisture is withheld it dries
up. From almost innumerable larve collected during several years I
have only been successful in rearing two or three specimens, enough,
however, to determine the species, and, as the moths are always abun-
dant early in the spring on the trunks of orchard and forest trees, there
need be no scarcity of specimens for the cabinet.

Adult.—The moth expands 15™™, wings rather narrow. In color it closely simulates
the bark of the trees on which it naturally rests. The vestiture of the head is brown
interspersed with gray; palpi and antenne cinereous; thorax and abdomen pale
brown. Primaries brown, with a series of oblique double silvery streaks all along
the costal edge, extending about one-fourth across the wing; a large silvery spot of
irregular outline, inclosing a patch of dark brown, is situated near the outer edge of
the wing, and a less distinct patch of silvery scales occurs on the inner edge near the
middle, while a shading of the same color modifies the brown tint on other portions
of the wing. Cilia pale brown and cinereous intermixed. Secondaries cinereous,
_ shading on costal edge to pale brown; cilia dingy white. There is some variation
in distinctness of the markings and depth of coloring.

STEGANOPTYCHA PYRICOLANA Riley MS.—This is somewhat similar
to the above in coloring, but smaller and proportionally broader winged.
This bores the shoots of the second growth of apple in August and Sep-
tember, occasionally on recently planted trees, inflicting serious damage.
The larva spins scarcely any web, but bores downward through the ter-
minal bud, eutering the stem for from half an inch to an inch, sometimes
blackening all the growing points of a young tree.

Larva.—When full grown it is 8™™ long by 14™™ in diameter, slender, subeylindri-
cal, tapering slightly in both directions from middle segments; surface smooth;
incisions deep; color, pale cream yellow, somewhat translucent ; the dorsal surface
beautifully mottled with rose red. Piliferous warts and hairs only discernible with
alens. Ventral surface pale, slightly concave, and much wrinkled. Head elongate,
cordate, pale brown, shading to dark brown on the middle of each lobe; trophi prom-
inent, dark brown, with two or three long light hairs on each side. Supra-anal
plate oblong, large, dark, smoky brown. Legs and prolegs rather unusually de-

veloped.

I failed to rear the first specimens collected, most of them wandering
around in the jar until they died. Subsequently, by supplying them
with bits of pith or bark in which to bore, I succeeded in getting three
or four imagos between the last of September and the first of October.

_ 63

The moth expands 19™™, The head, thorax, and abdomen are densely covered
with long hair-like scales, of a dull gray-brown color with bluish reflections. Basal
half of primaries of similar color, but with more intermingling of blue and brown
scales. About the middle the wing is crossed by a broad, irregularly outlined band
of rich brown, sparsely intermingled with silvery scales, and the terminal third is
quite evenly mottled in brown and leaden gray, the costal edge of this portion being
ornamented with alternate oblique light and dark streaks extending about one-
fourth across the wing; cilia bluish gray ; secondaries lustrous pale brown, shading
to cinereous on costal edge; cilia dingy white. :

Professor Fernald, to whom a specimen was shown, considers it iden-
tical with Clemens’s S. salicicolana, which I believe breeds in willow galls,
but Dr. Riley pronounces it distinct, and he has types of Clemens’s
species.

GELECHIA INTERMEDIELLA ? Chambers.—This pretty Tineid appears
in its larval form on the tender leaves of apple early in May and again
in September. It gnaws the parenchyma from the upper surface, giv-
ing the leaves a burned and eroded appearance.

Larva.—8™ in length when mature, slender, cylindrical, tapering slightly in both
directions from middle ; incisions deep, giving it a submoniliform appearance. Gen-
eral color bluish green, acquiring a purple hue at maturity, with faint longitudinal
stripes of cream white. Head pale brown with a tinge of green, ornamented with
cream-colored markings on each side and arow of graduated cream-colored dots down
the middle of the face. First segment narrow, without perceptible shield. Thoracic
legs long, whitish, proceeding from papillated projections on the ventral surface.

This larva covers the leaves with fine web, in which it moves with
creat agility, and in which it rests suspended, without touching the
surface of the leaf, except when feeding. It is semigregarious and very
irregular in its development, some clusters of the leaves showing very
recently hatched young, while on other clusters they will be full grown.
It pupates on surface of the leaf under a little round cover of dense web,
similar to those under which some spiders protect their eggs. The
moths emerge in about 3 weeks after pupation and hibernate in the per.
fect state. |

Adult.—A beautiful species, expanding 12 or 13™™, Head and thorax dark gray,
more or less suffused with crimson; palpi dark gray, annulated with rosy white or
pale pink. Ground color of primaries leaden gray and rosy white; scales about
evenly intermixed. Three very irregular and variable, often interrupted, bands of
rich olive brown cross the wing, intermingled with some light golden brown or
ochreous scales; near the base and center of the wing these form quite distinct

_ patches. The apical third of the wing is margined with alternate dark brown and

rosy patches; cilia gray. Secondaries cinereous, with paler cilia. This species is
closely allied to both roseosuffusella Clem., and rubensella Cham., resembling in colora-
tion the latter and in size the former. Mr. Chambers says of it: ‘‘ Intermediate be-
tween roseosuffusella Clem., and rubensella Cham., with one or the other of which it
has hitherto been confounded. The third joint of the palpi is longer and more
acute than in rubensella, more like that of roseosuffusella, but the fore wings are much
less roseate than in either of the two other species, frequently showing no tinge of
the roseate hue. * * * Asgin rubensella (and sometimes in roseosuffusella), the first
dark band does not cover the base of the wing. The second band is like that of
roseosuffusella, but the third extends across the wing, the dorsal portion being, how-
ever, paler than the costal, and the costo-apical part of the wing is ochreo-fuscous,

54

This description, or rather these distinctions, of Mr. Chambers apply
to some examples, while to others they do not. Many specimens are
very roseate and richly colored, while a few appear almost plain black
and dull white. The three species are best distinguished in the larva
state, in which there are very decided differences. G. roseosuffusella
feeds on Clover, G. rubensella on Oak, while the species under con-
sideration, so far as my observations show, is confined to Apple. The
larval characters are also very diverse in the three species.

EXPERIMENTS WITH INSECTICIDES.

During the great prevalence of Aphidide in the spring I made much
use of pyrethrum and of the X. O. dust. Of the value of the former as
a remedy for these pests, except in the case of one or. two species, I
have no occasion to change the favorable opinions already repeatedly
published. The X. O. dust was thoroughly tested on the following
Aphids: Aphis mali and Schizoneura lanigera on Apple; Aphis prunifolit
on Plum; Siphonophora rose on Rose; Myzus persice on Peach; Aphis
brassice on Cabbage; Aphis sp.? on Cucumbers and Squash; Siphono-
phora sp.? on Lettuce; S. crategi on Thorns; S. rudbeckice on Solidago;
Aphis ambrosie ou Ambrosia trifida, and Aphis chrysanthemi? on Chrys-
anthemum. With its effects on all of these I was well satisfied, although
in some cases it took several dustings to thoroughly clear a plant.
When applied with a powder bellows it causes the insects to drop to the
ground at once, where they may be pressed into the soil with the foot or
patted down with a trowel. The more delicate species succumb to a
single thorough dusting and never recover from the effects of contact
with the powder. This preparation will also destroy Siphonophora
avence, but whether it could in any way be applied to a field of infested
grain has not been demonstrated.

The Black Chrysanthemum Aphis is one of the greatest pests of the
flower garden and gives much trouble to both amateurs and profes-
Sional florists. It hibernates on the plant and attacks the stolons as
soon as they appear in the spring, and unless great care is taken to
eradicate it, it is more or less numerous on the plants throughout the
summer, dwarfing and deforming them by its punctures and by the loss
of sap which it appropriates. As soon as the buds are formed it seems
to develop with four-fold fecundity and requires assiduous attention to
keep in check. The Buhach or pyrethrum powder is utterly useless
against this species, probably because the plant from which it is made
is so close an ally of the Chrysanthemum. The X. O. dust, composed
of creosote and tobacco, is the best remedy within my knowledge, killing
the Aphis without the slightest injury tothe plant. Ihave found it
best to apply during the middle of the day when the dew is off. A few
minutes after dusting the plants, I pass along the rows or among the
pots, and give each branch a smart shake ora blast of air from the
empty puff, and every Aphis that has not previously dropped is dis- |

55

lodged, and ‘‘to make assurance doubly sure,” it is stamped into the
earth. On most of the insect foes of the plant lice the dust produced
no disastrous effect, but the larve of Syrphide would, in some cases, not
recover from the pungent coating.

Arsenites of ammonia.—This new preparation, for which F. J. Andres,
25 Pearl street, New York, is the agent, was sent to me for experiment,
in accordance with directions from the entomologist of the Department
of Agriculture. It did not reach me until about the 1st of June, too
late for use on a number of insects. It is a clear solution of arsenic in
aqua ammonia, and apparently does not differ much from a preparation
of my own devising, as reported on two years ago, and with the effects
of which on vegetation I was not entirely satisfied. The directions ac.
companying each of the gallon bottles, in which it is put up, are to use
one tablespoonful of the liquid to a gallon of water.

June7.—Weather clear and hot. Prepared a quantity of the fluid as di-
rected and had it applied to the following plants: To potatoes, on which
were a few Doryphora larve; to rose bushes, on which still lingered a
few larvee of Selandria rose, Characlea angulata, and Amphipyra pyrami-
doides; to cabbage, covered with full-grown and young larve of Pieris
rape; to cucumbers and squash infested with Diabrotica. It was too
late in the season to test it thoroughly on apple for the Codling Moth,
and as there were scarcely any peaches or piums or curculios, its effect
on the latter insect can not be reported upon. Portions of the trees as
well as of cherry were sprayed to discover its effect upon the foliage.

June 9.—Made the rounds of all plants sprayed and noted results as
follows:

Potato plants slightly scorched, edges of the leaves curled, larve of
Doryphora mostly on the ground dead, beetles sickly.

Rose bushes uninjured, or very slightly burned where the leaves were
very tender; all larve killed. |

Cabbage uninjured; all Pieris and other larve killed. Cucumbers
much injured, squash less so; striped beetles killed or vanished.

Peach ard cherry foliage badly scorched, turned yellow. Plum and
apple only slightly injured. Other experiments later in the season
made with one tablespoonful of the poison to one and one-half gallons
of water were not injurious to any except the most delicate foliage,
while in most cases it sufficed to kill Sphinx quinquemaculata and Helio-
this armigera on tomato, Darapsa myron, Cidaria diversilineata, Psycho-
morpha epimenis, and De.mia maculalis on grape, with but slight damage
to the foliage. The fruit being ‘“‘bagged” was not touched by it.
Empretia stimulea on plum and pear and Datana ministra on oak also
speedily died from eating leaves that had been dampened with it.

I do not consider these experiments conclusive, as with the heat and
drought, vegetation was not by any means in a vigorous condition, and
therefore more liable to injury from poisonous applications. It is a
most convenient preparation and leaves no sediment to disfigure the

56

foliage, and will, I trust, be found, by more thorough experiment,
efficient as an insecticide when used of a strength that will preclude
injury to foliage. sg

Late in the summer a preparation of petroleum sludge with soap
was sent me from the New York Chemical Works for trial, but there
were very few insects at that time on which to test it, while its almost
intolerable and persistent odor is really a serious objection to its use,
especially in small gardens.

In making my experiments, I have used the Lewis Combination
Force Pump and Syringe, and consider them well adapted for use in
small orchards and vineyards, and especially adapted for purposes of
experimentation, where the larger and heavier appliances are not
necessary. -

REPORT ON WORK OF THE SEASON,

By HERBERT OSBORN.

LETTER OF SUBMITTAL.

AMES, Towa, October, 1899.

Sir: I transmit herewith a report upon the work of the season, including mention
of certain insects that have been observed during the season and notes regarding
certain others, observations on which are in progress, with the expectation of giving
more detailed accounts of their life histories and habits.

There is much yet to be done on the insects affecting grass before anything like a
full report can be made upon them, but I shall hope to bring the work of the present
season into shape for submission at the end of the year.

The work on the parasites of domestic animals has been continued and a part is
already submitted for printing, while a considerable amount of other matter is in
form to be presented at an early date.

Very respectfully,
HERBERT OSBORN.

Prot... Vi. RILEY,

U. S. Entomologist.

During the past summer there has been no great depredation by any
single insect pest in the State, but a number of the common species of
insects have been working with their accustomed energy, and the losses
from this source in the State have Erepab sch been up to the average of
ordinary seasons.

The observations on insects affecting grass crops have been continued,
and I am only the more strongly impressed with the importance of ans
insects affecting these crops in this State, and believe that the estimates
given in my last year’s report as to the probable loss from this source
to have been by no means overstated.

Judging by the reports of the correspondents of the lowa Weather
and Crop Service, who represent every section of the State, the insects
that have caused most extensive injury are those infesting meadows
and pastures and sod land planted to corn. Not only are there numer-
ous reports of injury by insects to timothy, to pastures, and to corn
planted on land previously in grass, but numerous mention of poor

condition in meadows and pastures, shortage in grass and hay crop,
57

58

=

ete., which, to any one familiar with the great number of insects now
infesting grass land in this region, tell a certain story as to at least one
of the great sources of loss. :

Frequent mention is made of the Cutworms, Grubworms, Wire-
worms, etc., and it is evident that a very great variety of species are
included in this list; but while I am certain that many species of Cut-
worms belonging to the common species of Noctuide are included in
this list, I believe that much of this injury is due to the species of
Crambus treated in detail in my report for 1887, the Dried Crambus
(Crambus exsiccatus), or as called in the larval stage, the Sodworm or
Turf Webworm. ‘This has been very plentiful here in the adult form
the present season, though by no means so abundant as in 1887, and I
have no doubt that it has been as abundant in other parts of the State.
The work of this species in meadows, however, would not be readily
distinguished from that of Cutworms by those unfamiliar with the
habits of insects, and even in corn the effect on the plants is not easily
to be distinguished from the effects of Cutworms, Wireworms, or other
forms of insects attacking the stalks at or near the surface of the
ground.

LEAF HOPPERS IN GRASS.

In my report of last season I mentioned a number of species of leaf
hoppers (Jasside) that are destructive in grass land. Further observa-
tion and collection in this same line has served to strengthen my opin-
ion as to the great amount of injury to be attributed to these minute
insects. A number of species particularly of the genus Deltocephalus
occur in immense numbers in grass land, and among the most common
of those observed here are the Deltocephalus (Jassus) inimicus Say,
treated of in last year’s report, but associated with these are D. debilis
Uhler., D. Sayi Fitch, D. Melsheimeri Fitch, and a number of species
apparently as yet undescribed. A fuller report upon these I hope to
make a little later when material on hand can be more fully examined
and a more complete statement of results given, but it may be in place
to mention as one of the results of this study that I have been con-
vineed that these insects are a very important factor in the production
of “ silver-top ” in grass, this being one of the effects produced by their
suction of the juices of the plant and resulting when they penetrate the
succulent portion of the stem at the base oi the terminal node. That
other insects may and do cause this same form of withering and injury
to grass I do not deny, butin a great number of examinations of injured
stems I have in the great majority of cases found no insect within the
sheath of the injured part, and feel positive that for these the injury
could not have been produced by Thrips or Meromyza or any insect
working within the stem while the presence of immense numbers of the
leaf hopper on the affected plants and the presence of punctures show
clearly the possibility of the injury being due to them. |

59

_ This question has been more fully discussed in a paper read with
your consent before the Association for the Promotion of Agricultural
Science at the Indianapolis meeting. In that paper I have refetred to
different explanations for the silver-topped condition of grass and pre-
sented the grounds for my own opinion that for this locality and in
blue grass the injury must be referred mainly to these Jasside. From
the fact that these Jasside are exposed to the application of remedies
that would not affect insects protected in the sheath it is evident that
the adoption of measures to destroy these, as suggested in my last
year’s report, should result in a decrease of the ‘ silver-top.”

GRASSHOPPERS AND CRICKETS IN GRASS.

The common species of grasshoppers or locusts have been as usual
very plentiful, Melanoplus femur-rubrum probably heading the list for
abundance, but several other species, as M. differentialis, Dissosteira
carolina, Tomonotus sulphureus, and Arphia sordida form a very con-
Spicuous part of the grass-eating species. For the present season also
there has been a very great abundance of the little field cricket, Nemo-
bius vittatus. This was noticed as especially abundant on sunny hill-
sides in pastures and in many places aggregated in such numbers
as to completely cover the surface of the ground. While this species
has been rather frequently mentioned among the species common
throughout the country and its herbivorous habits accepted, so far as

,1 know by all, there has been apparently little attention to it as a de-
structive species or one worthy of particular attention on account of
- the injury it may cause in pastures.

Tt is quite evident, however, that when occurring in anything like the
abundance in which it has been observed here this season it must be
the cause of no little loss, and it may very well be associated with the
more frequently mentioned locusts in the category of destructive ©
meadow insects. ,

MISCELLANEOUS NOTES.

The Apple Leaf Skeletonizer (Pempelia hammondit) has been sent me
this season from near Des Moines, where it was reported as doing con-
siderable damage. This insect has been comparatively rare in the State
for a number of years, but from the account received of its appearance
this year it must have been in such numbers as to cause no little dam-
age, and it is to be hoped that prompt measures will be adopted by the
fruit-growers of that locality to prevent its spread.

The Turnus Butterfly (Papilio turnus) has been noticed as more than
ordinarily abundant, the larve occurring in considerable numbers on
various trees, especially on plum trees in this vicinity. While the species
has seldom assumed an economic importance, in this State at least, it
may be that it will require occasional attention, and it will of course
readily succumb to the treatment by spraying, so efficacious for leaf-

eating larve.

60

The Cherry Slug (Selandria cerasi) has also been quite plentiful and
damaging cherry and plum trees. It would appear that this insect has
been rather more than usually common in a considerable territory the
present season, as I have heard of it from various localities. Itis gen-
erally the case, however, that it does little damage for more than one
or two seasons in succession, so that it seems hardly necessary to take
any great amount of trouble in dealing with it unless itis working
destructively upon particular trees, when the usual poisonous sprays
suffice to rid the trees of its presence.

The Handmaid Moth (Datana ministra) has been on the increase
apparently for a number of years past and for the last two years has suc-
ceeded in defoliating quite a number of trees in the vicinity, especially
hickories and black walnuts. As mentioned in another place, the
arsenite of ammonia was used in treating it this fall and proved very
efficient in destroying the insects. Previously, we have used London
purple for this purpose, and there is apparently little choice, unless
there be sufficient difference in price to render one cheaper than the
other. Itis important in using any of the poisonous solutions for this
species to spray the whole tree or as much of it as possible, since when
only the part where the worms may be working at any particular time
is sprayed, they are very likely in their next move to occupy some part
where there is no poison to affect them, and they may in this way escape
until they have caused considerable damage to the tree.

Abbot’s White Pine Worm (Lophyrus abbott) has appeared in the
State, and so far as I am aware it is the first time that this destructive
insect has been brought to notice in Iowa. It was sent to me from
Farley and with the report that the evergreen trees were suffering
severely from its attacks.

The Corn Root Worm (Diabrotica longicornis) is evidently on the in-
crease and gradually extending throughout such localities as it has not
hitherto occupied. Here, it appears very abundantly in the adult stage,
and in fall, collecting in great numbers on flowers. So far as I know
there has notas yet been any very great injury to the corn in the vicinity,
but probably the worms occur in considerable numbers scattered through
the various fields, and it is probable that in a short time they will mul-
tiply to such an extent that in fields kept long in corn they will cause
Serious loss.

The species of Diabrotica infesting squashes, melons, ete., D. vittata
and 12-punctata, have been very abundant the past season, though per-
haps not more so than is common for them, but the crops they infest have
required attention in order to prevent serious loss.

The Potato Stalk Weevil (Zrichobaris trinotatus) was observed this
season for the first time and occurred in such numbers as to cause con-
siderable damage. It was first noticed by Mr. F. A. Sirrine, a special
student in entomology, at present assisting in the botanical work in the
Experiment Station. It is quite likely that the insect has been present

61

in previous seasons in small numbers, but it has not been taken evenin
the adult form, in this locality till this summer, so that it seems more
likely that it has been introduced in some way quite recently.

TESTS OF ARSENITE OF AMMONIA.

During the month of May I received instructions from Mr. Howard
to make tests of an insecticide put on the market by Fr. Jac. Andres,
of 25 Pearl street, New York, under the name of arsenite of ammonia,
as agent for the Caspar Schneider Chemical Works. In due time the
samples came from the New York firm and I proceeded to make such .
tests aS were possible to determine both the effects upon various kinds
of plants and its effectiveness in killing insects.

On the morning of May 30, 1890, between 9 and 10 o’clock of a hot,
sunny day, I sprayed the following plants with a view to giving a
thorough test of the effect on foliage:

Squash vines infested with Drabrotica vittata.

Cucumber vines infested with Diabrotica vittata.

Potato vines infested with Hpitrix cucumeris.

Plum, Cherry, Box-elder, Willow, Elzagnus, Elm, Mountain Ash,
Birch, Apple, Raspberry, beans, grass, and clover.

The results were watched closely for a number of days but the record
of June 2 gives the results for the entire set. On that day a careful
examination was made of all the plants that had been treated and it
was found that in no case could there be found any injury to the foliage,
except possibly a slight injury to the elm and the beans, but the injury
was so Slight, ifany, in these cases that it could hardly be charged with
certainty against the arsenite. The solution in this case was as given
in the directions, a tablespoontul to an ordinary pailful of water, and
the conclusion was that with this strength it could be applied without
danger to any of the above-named plants.

On the squash vines and cucumber vines the beetles seemed much
less abundant, but I was unable to find any dead insects around the
vines. The hills treated, however, remained quite free from further
trouble from these insects, while others in the vicinity were seriously
affected. The failure to find dead beetles under the treated plants
might easily result from the insects flying away after eating the poison
to places of shelter and dying there. The same was true of the flea-
beetle affecting potatoes. The beetles seemed much less abundant, but
no dead ones could be found under the treated vines.

While it was so late in the season that it was not expected that this
test would give any definite results as to the effect on the codling moth,
it is worthy of mention that the branches of the apple tree sprayed
with the arsenite were loaded with apples, while the other portions of
the tree were much less fully loaded.

The apples also of this portion were quite free from worms, though
in the late fall they were of course exposed to the action of the second

62 —

brood and a portion of the fruit was found infested. While this is not
given as a good example of the effect of spraying, it seems strong enough
certainly to warrant the conclusion that the arsenite of ammonia will
prove as effectual as any other form of the poison against this pest.

There were none of the Colorado Potato Beetles to be found in the
vicinity, so the poison could not be tested with them, a test that would
have been of course more satisfactory, especially with the larvee, because
of the fact that the dead insects can afterward be found readily around
the treated vines.

I was able, however, to give a thorough trial of the insecticide prop-
erties of the substance later in the season on the common Handmaid
Moth (Datana ministra), which was very plentiful on some of the hickory
and black walnut trees in the vicinity. A single application of the
poison was found to kill the caterpillars in large numbers, evidently af-
fecting all that fed upon the leaves that had been reached by the poison.
Dead caterpillars began to be found in 24 hours from time of application,
and for two or three days afterward the caterpillars were dying off rap-
idly. The application was in this case madea little stronger than in the
first trials, and in a few days the trees showed some injury from the ef-
fects of the arsenite, so it seems quite evident that the strength for these
trees must be kept within the limits indicated by the directions. The
liquid is very convenient to mix with water, and forms probably a very
uniform mixture, so that it seems to possess some points of superiority
ver the arsenites in solid form.

REPORT ON SOME OF THE INSEOTS AFFECTING CEREAL
CROPS.

By F. M. WEBSTER.

LETTER OF SUBMITTAL.

LA FAYETTE, IND., October 22, 1890.
Str: I herewith submit my annual report of observations on some of the insects
affecting cereal grains. For assistance in carrying on the experiments connected
with the studies of the Hessian Fly, Iam greatly indebted to the following gentlemen:
Hon. Samuel Hargrave, Princeton; Mr. W.S. Ratliff, Richmond; Mr. Miles Martin,
Marshall; Hon. W. Banks, La Porte, and Hon. J. N. Lakta, HEA pacelie to Purdue
University, and later the experiment station. I am also under obligations for use
of land, seed, and labor in carrying out my own experiments here at La Fayette.
To yourself especially, and others of the division, Iam under many obligations for
the determination of specimens and other numberless favors.
Respectfully submitted.
F, M. WEBSTER,
DroCoWV. RILEY,
U.S. Entomologist.

THE HESSIAN FLY.
Number and Development of Broods.

My experiments, notes, and observations upon this insect extend
over a period of a little over six years, and while it received little more
attention than was given other wheat-destroying species, a considerable
number of facts have accumulated which, while not by any means
clearing up all of the mysteries of the pest, will nevertheless serve to
throw some light on several obscure points. Unless otherwise stated,
all of my observations and experiments herein recorded relate to the
State of Indiana, extending from latitude 37° 50’ to about 41° 45’ N.
The exact latitude of many places of observation is given, not so much
for the American reader or investigator as for those of other countries,
notably England and Russia.

My experiments and observations have been carried on almost exclu-
sively out of doors and very largely in the fields, as 1 consider indoor

and breeding-cage observations on this species, except for the purpose
63

64

\

of securing specimens and parasites, of very doubtful value from an
economic standpoint or as indicating its normal habits. The observa-
tions have many of them been once and often twice substantiated.

In ordinary seasons and throughout the area above indicated the
statement made long ago by Dr. Fitch that the Hessian Fly is double
brooded is true. While in the southern portion of the State the fall
brood of adults seem to appear some weeks later than in the northern
part, nevertheless I have found but two destructive broods. Between
these two broods, however, is a considerable mass of fluctuating indi-
viduals, the true position of which is rather anomalous.*

At LaFayette, Ind., latitude 40° 27’, wheat plants were transferred
from the fields to the breeding cages April 5, 1890, and kept out of
doors. The seed producing these plants had been sown the preceding
September 3. On April 17 a female emerged, and a male appearing
soon after, these, on April 22, were both placed together on young
growing wheat planted in a breeding cage, out of doors. From these
adults were secured June 8. The attempt was made to follow the off-
spring of these, but failed on account of the wheat being killed by rust.
On June 7, and also on the 14th, 1888, in the same locality, adults were
observed ovipositing, the eggs being placed on the youngest and most
tender shoots, and there was every evidence that these eggs developed
through the larval to the flaxseed stage by early July. Besides, I have
observed in the same locality late-growing shoots literally overrun
with very young larve on the 26th of June, and found larve as late as
the 10th of July.

On October 16, 1887, Mr. W. 5S. Ratliff, who made a great number of
experiments for me, near Richmond, Ind. (latitude 30° 51’), secured
adults from a small plot of wheat plants which appeared above the
ground September 4. From a plant from this same plat that had been
transplanted indoors, he secured an adult female 11 days earlier. In
either of these cases with favorable weather the female could have.
sent her offspring into the winter in the flaxseed state. Mr. Ratliffalso
observed adults on July 10, 1887. At La Fayette, Ind., the same au-
tumn, I saw females ovipositing on November 3, in a temperature of 64°
F., among the plants. From a platsown August 13, and which came up
on the 17th, I obtained adults of both sexes on October 1, 44 days after
the plants appeared and 48 days after sowing. That larvae, even
though quite immature when winter begins, may survive till spring has
been demonstrated again and again, and was especially true of the
exceedingly mild winter of 1889-90. In fact, by a series of sowings all

* Dr. Fitch states that the eggs of the fall brood are deposited in the State of New
York early in September, and also that ‘the deposit is doubtless made later to the
south of us than it is here in New York.” (Seventh Report.) Mr. Edward Tilghman
observed oviposition in Queen Anne’s County, Maryland, about latitude 39° to 39°
30’, during the second week in October, and mentions it as of usual occurrence. (The
Cultivator, May, 1841.)

Reet Hist yces

65

stages of the insect can be produced continually from April to October,
and by keeping a cage indoors I have produced adults in abundance in
January. :

As Dr. Lindeman has well stated, the puparia are greatly influenced
by environment, temperature, etc., and this is probably true of the other
stages, larvee of different ages being, for all we know, influenced to a
different degree. To these facts must be added another of considerable
moment, viz, while nominally two brooded, flaxseeds collected by me in
the spring of one year have lived over to the spring of the following year.
This is also true of at least one of the parasites of the species. How far
the number of these interlopers is augmented by a retarded develop-
ment of greater or less extent it is impossible to say, but that there is an
accession through this means there can be no doubt. In fact, it would
appear as though nature had in this way provided against the extine-
tion of the species.

Now, is it proper for us, from these scattering individuals, to attempt
to construct distinct broods? Itseemstomenot. I have several times
sown wheat at La Fayette early in July and never had it seriously in-
fested by Hessian fly until late in August or early in September. Very
young larve were exceedingly abundant early in October of this year
in a field of early-sown wheat near La Fayette.

It is true that observations during a single season, in a single locality,
might produce apparently good evidence of a third brood, but a con-
tinued close study of the species in such locality will probably show it
unfounded. That these aberrant individuals may, under favorable con-
ditions, collect or ‘‘ bunch” together in certain fields is probably true,
but my own experience has been that the following year this irregu-
larity will have disappeared or have been reduced to a minimum by the
effect of the weather during midsummer and winter. On June 24, 1887,
near Princeton, Indiana, latitude 38° 23’ N., I found a field of wheat,
sown about the first of the preceding November, literally alive with
larvee from one-fourth to nearly or quite full grown. There were no
pupz to speak of in this field at the time, but in other fields in the
vicinity these were abundant, but here there.was no larve to be found.
At this date wheat harvest was at its height. The late-sown field had
evidently attracted the late-appearing adults of the fall before, and
their progeny, living over in this field, as delayed larvz, emerged cor-
respondingly late in the spring, giving rise to the generation of larve
observed by me. My reason for taking this view is that I have several
times tried to draw off the spring brood of flies by offering them young
plants on which to oviposit, but have always failed, as they seemed to
prefer tender shoots of older plants to the young plants themselves. In
the fall this characteristic seems to be somewhat the reverse, although
even then, if attacked after tillering, the tillers will be chosen instead
of the main stem. The fall brood of adults is probably the migratory
brood, and their power of detecting wheat plants is almost phenomenal.

25910— Bull. 23——5

66

I have drawn them to a small plat of wheat sown in a secluded corner
of my garden, in the midst of town, fully half a mile from any wheat
fields. But, be this as it may, a second brood of larve in June would
be rather difficult to sustain, as the puparia of the earlier part of the
month are known to remain in that stage until September. Neither
have I been able to secure any better evidence of a brood originating in
volunteer wheat during July and August. Puparia are to be found
every year from one end of the State to the other in this volunteer
wheat, but here in Indiana I have never found these sufficiently numer-
ous to imply a distinct brood. Professor Forbes and his assistants,
working in Illinois, appear to have a greater confidence in this extra
brood than myself, although, as will appear farther on, our experiments
were carried on the one perfectly independent of the other, though only
a few miles apart.

My attention has been called to the condition of this field near Prince-
ton, by Honorable Samuel Hargrove, member of the board of trustees of
Purdue University, and also a member of the State Board of Agricul-
ture, who willingly agreed to further aid in the investigations by sow-
ing for me plats of wheat at intervals of about 2 weeks, beginning as
soon as possible after harvest. Being detained in Louisiana myself
until nearly the Ist of August, and the weather being exceedingly dry,
no plats were sown until August 4, 1887, followed by another on August
22, and a third September 5. These were sown on one of Mr. Hargrove’s
farms, about 10 miles northeast of Princeton.

The first two sowings, owing to the drought, came up sparingly and
about the same time. The third was also affected by drought, and did
not come up until about the Ist of October. These plats were sown
along the lower edge of a high, rolling stubble field, which had been
too dry to plow, and in which I had found an abundance of flaxseeds
the preceding June. }

These plats were examined by me on October 8. The two earlier-
sown plats had thrown up a good growth of plants, which had tillered
finely, being along a low ravine. On these plats I found a number of
larvee, which were nearly or quite grown, and a less number of flaxseeds,
one of which was empty. Besides these, the plants were literally alive
with very young larve, so young, in fact, that they had not yet lost
their reddish tint. The third plat had sent up the normal number of
plants, which were now in the second leaf. These plants had not ap-
peared in time for the earlier deposited eggs, but were even more seriously
infested by young larve than the plants of the two earlier plats. One
of the plants from the last plat is before me, and contains twenty-six
young larvee, all of which must have hatched from the eggs only a few
days prior to my observations. Now, from whence did the progenitors
of these young larve originate? Most assuredly not from volunteer
wheat, because there was none. Nof from my earlier-sown plats, else
these would have shown the effect. There are, it seems to me, but two

67

other sources from which they could have come, viz, the stubble, which
I know to have been infested, and grasses, which we have no knowledge
of the species affecting. tins <:

These plats were plowed up soon after examination, as I was afraid
to allow them to stand thus, a menace to the adjoining fields the follow-
ing spring, though the plants would have probably been destroyed
before even a small portion of the larve matured.

From all the information that I am able to gather, the usual time of
appearance of the fall brood of adult flies in southern Indiana is the
last portion of September, or some years the first days of October.
This is, I believe, the opinion of the most observing farmers, including
Hon. J. Q. A. Seig, of Corydon, Harrison County, who is as familiar
with the earlier stages of the pest and its effect upon fall wheat as I
am minyself. Mr. J. P. Londen, of Sharp’s Mills, same county, stated
that wheat sown on October 1, 1886, was damaged 50 per cent., while
that sown on the 6th was injured only 15 per cent. Mr. J. A. Burton,
writing from Mitchell, Lawrence County, November 24, 1887, gave the
results of his examination of wheatfields as follows: Fields sown Sep-
tember 8, about one plant in 8 infested; sown September 15, about
one plant in 12; sown September 22, about one plant in 50, and
sown October 1, seemingly free from injury. The observations of these
gentlemen also coincide with my own, made in November, 1888, in Har-
rison and Posey Counties. Therefore, from all the information which
I have been able to gain, the best season for wheat sowing, to avoid the
attacks of the Hessian fly in extreme southern Indiana, is soon after
the 1st of October. Exactly how far northward this advice will apply
I am unable to say, but am inclined to think it would cover territory
laying between latitude 38° and 39°, and possibly 39° 30’, although
near the northern limit it would probably be safe during ordinary years
to sow soon after September 25.

During the years 1887 and 1888 Mr. W.S. Ratliff made a large num-
ber of very careful observations, and sowed a series of plats of wheat
on different dates near Richmond, Ind. In 1887 plats were sown August
5 and 29, September 12 and 26. All of these plats were attacked and
more or less injured except the last, which as late as December 19
showed not the least injury by the Hessian fly. Up to May 31, 1888,
there was very little injury to this plat, and even on the above date
there were very few larve as compared with the number on the others.
From this date on till July 11 the plats were all injured by black and
red rusts, Chinch bugs, and the Wheat Stem maggot, the greater injury
appearing to fail upon this, so that at harvest, July 11, the last was
the poorest of allin yield, that sown August 15 being the best. The
sowings of 1888 were as follows: September 6, 20; October 4, 22; No-
vember 1. On November 14 the first plat was found to be infested by
larvee of the Hessian fly. During June, 1889, Chinch bugs again at-
tacked the plants growing on these plats, and the grain aphis seriously

68

injured the later sown plats, So that at harvest, July 5, these latter
were the poorest of all, the other three averaging about alike. All of
these plats during both years had been sown in narrow strips among
corn along one side, the remainder of tbe field being corn, and later
also sown to wheat, thus bringing the latest-sown plats between those
sown earliest and the entire field itself, as appeared to me, the severest
test to which I could subject the several plats. The results, while not
conclusive or even entirely satisfactory, indicate that in that latitude
about September 25 is, generally speaking, a good time to sow wheat
to escape fall attacks of the fly and winter killing. A series of plats
sown for me by Mr. Miles Martin, of Marshall, Parke County, Ind., in
very near the same latitude as Richmond, but nearer the western border
of the State, gave rather more conclusive results, the sowings of Sep-
tember 22 being almost entirely exempt from the attack of the Hessian
fly, while earlier plats were infested.

In regard to my own experiments here on the Experiment Station
grounds at Lafayette, 1 may state that I have never been able to pro-
voke a disastrous attack of the pest, though there has been nothing left
undone which could possibly induce the adult flies to oviposit at any
time between March and December; and there is probably not a month
between these dates during which the insect could not have been found
in all of its stages. The two destructive broods, however, invariably
appear in May and September; in the latter case usually before the
20th. 3

My own experimental showings were rather more elaborate and ex-
tensive than those of any of my correspondents, comprising a number
of varieties and extending over several months. Without going into
details, the experiments and results may be summarized as follows:
1887, plats comprising the varieties Michigan Amber, Clawson and
Velvet Chaff, each one width of a grain drill twenty rods in length, were
sown on the following dates: August 13, 27; September 10, 24; QOcto-
ber 8, 27; November 5,19. The autumn was very dry, and the plants
of the first six plats went into winter in poor condition, being very
small, while the last two sowings did not come up until the following
spring. The severe winter destroyed the plants so generally, that only
the first three produced suticient grain to pay for harvesting. These
were also the only ones to suffer from the fall attack of the fly, the first
producing adults October1. Plat8 was attacked on the following June,
and on the 26th was badly infested with young larve, full-grown larve
and puparia, the latter, the most numerous, were found on the 16th of
July. The plats harvested produced a poor crop, but the Michigan
Amber ranked first, Velvet Chaff second, and Clawson the poorest of all.

69

The condition of the Hessian fly in these three plats, at the time of
harvest, July 10, 1888, may be inferred from the result of examinations
made on this date.

mM bye llaxsee Gps serra si emeeia cerns <lsicc cis csisiejciclerna adil ane ec ewlcc es 15
Containing healthy pups or parasites........------...----..----- 69
Wat Wiceper teers einicle oe tania ialteac cna ssc ce bidaniss scacce taeces steele « 16

INOUAN Beso SCE CSS SOD SON BREA SHRI OOEE CC See nee EOE Rene anaes 100

August 3, the state of the insect in these same plats was as follows:

Emp byetlaxceedisjnmc cae. om ebeinctem ao aa/7 2 as ieceiceicwicissekivics ssics = 53
Containmo healthy. pupagandi parasites: --52--5.s<c04-25-+---2<0 47

HO Galles Seay See eee ets Deis Ss See ere ote 100

The condition of the insect on September 1, as shown by examination
of the stubble, is indicated below:

map byetlaxscedsinyeeets sem catele rs cele cae sae tre ats Sa ae ease ece dee ‘ 55
ee altmyailaxscedsm smmeminere ch tS ots ee hee UA Eee lS 28
FP ATASLUIZC Usa XSCCO ST Mase hice ion eee ee ne hele ome cet nee eee 17

CONG hes ct 5 Be ae NS a a Oa ee ee a i ek ne ee ey ee Le OO

Notwithstanding the per cent of healthy puparia passing the summer
was small, there is little probability that many adult flies emerged.
A plat of the same dimensions was sown July 16, along one side of the
first three sown the previous fall, the plants of this last sowing coming
up ten days later. This plat was closely watched. After July 17 only
an occasional larva was found. By August 4 plants had been de-
stroyed by the combined influences of chinch bugs and dry weather,
but a second plat has been sown adjoining, and the plants of this ap-
peared above ground on August 6. On September 4, 200 plants were
examined and but two larve were found thereon. A second examina-
tion of the same number of plants from this plat, on September 15, re-
vealed a small number of young larve. <A third examination of this
plat on October 6 showed about 1 per cent of the plants to be infested.
Stubble from the three original plats, keptin breeding cages, out of doors,
did not give adults until the 17th of September, although it is quite
probable that some few were abroad before that date. It will be seen,
however, that no great number could have emerged from the stubble,
and the increase in the number of empty flaxseeds between July 10 and
September 1is doubtless to be attributed to parasites. This appears all
the more probable, as I have repeatedly observed these parasites
during July and August emerge in breeding cages, and at once begin
to oviposit in flaxseed in the stubble from which they had themselves
emerged. The percentage of healthy puparia reaching September in
safety, however, was probably unusally small, as experiments on the
same ground the following year did not suffer near somuch from either
fall or spring attacks. Another feature of these experiments is, that
it strongly indicates that the jarger per cent of the parasites emerge
prior to the Ist of August. Indeed, stubble from the entire length of

70

the State, collected in June and placed in breeding out of doors here
at La Fayette, has indicated the truth of this.

The sowings of 1888 were made on August 30, September 18, October
3, 6. Ofthese, only the first sown were attacked in the fall, that sown
on September 18 being in the best condition the following July. Dur-
ing May, 1889, the plants of these plats were found to be much less
infested than some fields a considerable distance away, although such
fields had been sown on oats stubble, while the ground on which my
experiments were located was the same that had been used for this
purpose the previous year.

The sowings of 1889 were continued on the same grounds, the plats
being sown September 3-20, October 4-18, November4. The autumn
attack was the most severe on the first plat, but the extremely mild fall
and winter was so favorable to the development of the flies that the
spring attack was unusually severe, and appeared to fall upon the
three earlier sown plats with about equal force. ‘The later sown plats,
though the plants were much the younger, did not suffer so much, but
these were very seriously affected by the weather during early spring.

These experiments appeared to indicate that, in this latitude, while
wheat sown as early as the last of August may under favorable con-
ditions and during particular seasons produce as good or even a bet-
ter crop than when sown at a later date, yet such cases are the ex-
ception and not the rule; but that wheat sown as soon as possible
after the 20th of September stands the best chance of evading the at-
tacks of the fly and withstanding the unfavorable weather, the regular
operations of the University farm during the last seven years certainly
substantiate. It is the custom with the experiment farm, each year,
to sow the regular field crop at this time, and in no case has severe
injury been sustained from attacks of the Hessian fly. Fields on ad-
joining farms sown at earlier dates have frequently been seriously in-
jured, although this has not invariably followed.

Another series of experimental sowings was carried on for me by Hon.
W. A. Banks, near La Porte, Ind., about latitude 41° 35’. The first
series of these sowings was begun in August of 1887. The sowings of
1888 were not carried on under Mr. Banks’s immediate supervision, and
were of little value. No experiments were made in 1889, but a well
planned and carefully executed series were sown in the fall of 1890.
The series of 1887, each of which comprised two widths of a grain drill,
extended along one side of the field about 60 rods in length, the first
of which was sown on August 13, the plants appearing above ground
within a few days. The second sowing was on August 23, a third on
September 2, the fourth September 12, the fifth September 22, the
sixth and last on October 7. These plats were visited by me on Octo-
ber 14, and their condition found to be as follows: The first was found
to be infested by great numbers of larve and puparia, some of the
shells of the latter being empty, and the plants were seriously dam-

(fh

aged. The second plat was even worse injured than the first, and the
third much worse than either of the others. The fourth appeared to be
almost as badly infested as the third, but it had only partly tillered,
and hence there was a better prospect for it to throw up unaffected
shoots. The fifth had not tillered, and was only very slightly infested,
with very young larvee, while the sixth was not yet up.

On April 12, 1888, the plats were visited again. About 25 per cent
of the plants on the first three plats appeared to have survived. The
fourth was apparently 50 per cent better, the fifth was in almost
as good shape as the fourth, while the sixth was backward, the plants
being small and thin on the ground.

The estimate yield, made by Mr. Banks at time of harvest, on
the basis of 20 bushels per acre as an average yield, was as follows:
First plat, 50 per cent; second, 50 per cent; third, 65 percent; fourth,
90 per cent; fifth, 70 per cent. The remainder of the field was sown
on September 2, and shared in the destruction in common with plat
3. Another field at some distance from this was sown about Septem-
ber 20 and sustained no material injury.

It will be observed that the first three plats were sown almost at the
same time as the first three at La Fayette, yet stubble from the first
three plats at La Porte, collected on September 2 and placed in a breed-
ing cage beside another containing stubble from the first three at La
Fayette, gave adult flies nearly a week earlier. In other words, the
majority of the adults from Mr. Banks’s plats emerged prior to Septem-
ber 15, while those from my own did not reach their maximum num-
bers until after the 15th, and from then on till the 25th. In both
cases, however, a few stragglers emerged occasionally until early in
October. As previously stated, the plats of 1888 were not properly
sown, Mr. Banks not being able to attend to them himself; but a visit
to the locality on November 8 revealed but very little injury to wheat
which had been sown after the middle of September.

The experiment plats of 1890 were sown September 1, 10, 20, 30.
These were examined late in October and fully substantiated the ex-
periments of previous years. The sowing of September 1 was consid-
erably injured, while that of the 10th was very seriously affected, as
was also a large field adjoining sown but a day or two later. The sow-
ing of September 20 was comparatively free from attack, while that
sown September 30 appeared to have almost entirely escaped injury.

The sixth and last series of experiments were made for me by Hon.
J. N. Latta, at Haw Patch, Lagrange County, in about the same lati-
tude as La Porte. The scwings were made in 1887, the first being
drilled on July 28, but owing to drought the plants did not appear
above ground until about the 28th of August. The second plat was
sown on August 15, but came up the same time as the first; the third,
sown September 1, came up September 6; the fourth, sown September
12, came up September 21; the fifth, sown September 24, came up the

(Ze

28; while the sixth and last was sown October 12, and did not come
up until about the 20th. These plats were examined by me on Octo-
ber 17; the first three and the last sown were very poor, the fourth
and fifth promising a fair yield. <A field adjoining, sown on the same
day as plat 5, did not suffer from the fly and produced nearly an aver-
age yleld of 20 bushels per acre.

The results of these meager experiments have, as a rule, proven
correct in the fields of the farmers. I have not only observed this
myself, but it has become well known in the locality that wheat sown
before September 15 and after the 30th of the same month seldom pro-
duces a good crop, while that sown between the 15th and the 25th is
the most likely to escape the attack of the Hessian fly, and, as a general
thing winters, as well as that sown earlier.

In summing up the results of this entire system of experiments, it
seems that while no exact date can be Jaid down for the appearing of
the fall brood of fly in any precise locality, there is, notwithstanding,
a gradual delay in its appearance as we go from the north southward.
In other words, there is here a characteristic element in the life history
of the species which may be utilized by the farmer to his advantage.
Fruit-growers, I believe, estimate that in spring the season advances
northward at the rate of about 12 miles per day. This would be a
trifle less than 6 days per degree of latitude. If farmers in extreme
northern Indiana and southern Michigan can sow their wheat with
safety about the 12th to the 15th of September (and we have demon-
strated that the fall brood emerges largely prior to the 15th), and
farmers in extreme southern Indiana must delay sowing until after the
first days of October, there must be a general system of retardation,
which, if understood, may be used to advantage throughout the inter-
vening territory.

Starting in southern Michigan on the 12th to 15th and passing 4
degrees south to the vicinity of Evansville, Ind., we should expect
about the same condition of the Hessian fly during the first week of
October. That is, if we pass the danger line about the second week
of September in southern Michigan, we should expect to encounter it
again in southern Indiana in the first or second week of October. A
considerable correspondence and my own experiments indicate that
this is usually true. It is not to be supposed, however, that it is
possible for me to give precise dates for given localities, as there is
another element which is likely to figure in these calculations, viz, ele-
vation. It has been stated upon reliable authority that ‘‘an elevation
of 350 feet is equal to 1 degree of cold in the mean annual tempera-
ture, or 60 miles on the surface northward.” * While we can hardly
expect this to influence comparatively level countries like the State of
Indiana at least to any marked degree, extensive areas of high table-

*Drapevr’s Intellectual Development of Europe, Harper Bros., New York, revised
edition, vol. 1, p. 29. .

73

lands would be apt to show its effect more distinctly. There may also
be some obscure influence peculiar to the natures of the different soils.

It will be seen, therefore, that the experiments have fallen far short
of settling the whole problem, yet it seems to me that they have been
carried as far as profitable, and the matter is now in proper state to be
taken up by the intelligent farmer, whose experimental plats are his
fields. And it may be added that this is done with a feeling on my part
that whatever of truth there may be in the matter will stand as a nu-
cleus about which others may build, while whatever there may be of
error will as surely disappear.

THE EFFECT OF THE LARVZ ON THE PLANTS.

The effect of the larvee, especiaily on the young plants, does not ap-
pear to be generally understood, and I have myself been able to verify
either the figures or descriptions of Fitch and Packard only in excep-
tional cases. The swollen bulb just above the roots in Fitch’s figures
gives but a vague idea of the true appearance, while Packard’s figure
represents plants which have very evidently sprung from seeds only
slightly covered by thesoil. Besides, the former figure only represents
the condition of the plants long after the larve have done their work,
and the latter, aside from the shoot being shorter, gives no idea of the
appearance of an infested stem, as found in nature, growing in the fields.
The yellow color of the foliage—there is usually more brown than yellow
about it—appears later, after the larve are full-fed, and then itis largely,
at least, confined to the younger leaves, the older ones, under whose
sheaths the larvee occur, are killed by the freezing weather of winter. In
Circular No. 2 of the Agricultural Experiment Station of Purdue Uni-
versity I have given a representation of an infested plant fresh from the
field drawn from nature. The plant had been attacked soon after its ap-
pearance above ground and had not tillered. The leaves under these
conditions are broader, darker green, more vertical and bunchy. The
youngest leaf on a healthy plant as it unfolds and pushes upward is of
a tubular form and spindle-shaped, somewhat as represented in Pack-
ard’s figure of a healthy plant. In the case of an affected plant, the
stem having been destroyed below ground, the spindle-shaped central
leaf is always absent. The difference between a healthy and infested
plant is shown by a comparison of figures. If a plant has already till-
ered, each of the identical laterals, as they are attacked, will begin to
take on the form and color above described. It is, therefore, not only
possible to detect an infected plant without removing it from the
ground, but also to determine the individual tiller infested. Now, while
this feature of infested plants is so very clearly marked, at least after
the larve are one-third grown, and from an economic standpoint of so
much importance that it is surprising that it should have been over-
looked, yet I can not myself lay claim to the fact by right of discovery,
as it was pointed out to me by a farmer in the autumn of 1884, and was

74

x

the outcome of circular No. 1, issued in October, 1884, from Purdue
University. It was only after testing the stability of this feature in
various fields, under widely different conditions, that I placed. full
reliance upon its permanency. An illustrated circular of inquiry, No. 2,
issued by myself from Purdue University during the fall of 1887,
brought also a great number of replies, from among which I have
selected the two following, because of their widely separated localities
and the well-known ability of the writers:

CLYDE, N. Y., December 9, 1887.
DEAR SiR: In regard to the appearance of wheat plants infested with Hessian fly,
and as illustrated and explained by Fig. 3 of circular, 1 believe that it is correct in the
main, especially the darker color possessed by infected plants over healthy plants,
and this is, as yousay, quite different from the information given by Fitch and Pack-
ard; and you have published this quite constant and true form and condition for the
first time, I believe. I had noticed this somewhat a year ago, and in bringing up the
destruction done by the Hessian fly in a Grange meeting, I found that a number of
farmers reported this very condition, viz: when fields or parts of fields looked extra
dark colored and healthy, damage from the fly was to be apprehended there. Still,
the yellow color came after a while, especially with early-sown winter wheat in a
long autumn or the following spring. I think the spring brood are apt to select

tillers.
Truly,
W. L. DEVEREAUX.

Prof. F. M. WEBSTER,
La Fayette, Ind.

UNIVERSITY OF CALIFORNIA, COLLEGE OF AGRICULTURE,
Berkeley, December 15, 1887.

DeEaR Sir: Your favor of November 28, with circular relating to appearance of
grain infested with Hessian fly, received. The appearances you describe are quite
characteristic of fly-infested grain here, but it is not seen in the fall, for we do not have
any grain above ground at that time. The districts in which the fly is found in this
State are of narrow area comparatively near the coast. In these parts itis not usual
to sow grain until after the winter rains have wet the ground enough for plowing,
and sowing can some years be made as late as the last of February, and still do well.
It is better, however, both for the growth of the grain and baffling of the fly, to sow
in January if the soil is in proper condition. For these reasons we do not find the
flaxseeds until about the first of March, and then it is that the grain assumes the fea-
ture you describe. Itis a very bunchy growth, with very few yellow leaves and ex-
ceedingly few seed stems thrown out. On some of our plats there will not bea single
stem, but the grain will remain bunchy and low for weeks, and then will turn yellow
and die as the dry season comes on. On other plats there will be a seed stem thrown
out here and there, and a few heads will ripen.

Such is ny recollection of the appearance of past crops. We do not intend to sow
wheat and barley this year on our fly-infested ground, but the pest may follow our
sowing on another part of the grounds, and if it will be of interest to you, I will
watch the plants and send you specimens,

Yours very truly,

—

E. J. WICKSON.
Prof. F. M. WEBSTER,

Nae L

15

If the soil is rich and the plants are attacked before they have til-
lered, these last will be thrown out from the roots which are not
injured. These, if the fall be very favorable, and the winter does not
commence too early, will often winter through and produce stem-bear-
ing heads the following harvest. On the other hand, if the autumn be
dry, or the ground be frozen early in the season, the crop will probably
prove a failure. Thisis the reason why some fields will present a much
better appearance the following June, and give a much better yield
than could have been anticipated from appearances during the fall. The
practical value of knowing how to detect the infested plants readily

is in that the destruction may be observed and the damage estimated

long before the foliage turns brown or yellow, and the fields be plowed
up and resown or allowed to remain, as the owner judges best. If re-
sown, it would seem best to replow also. Mr. W. A. Oliphant, of Pike
County, southern Indiana, writing me in the fall of 1884, in reply to
circular No. 1, stated that of 300 acres he had resown 200 acres after re-
plowing, and 100 acres without plowing. The first yielded him 274 and
the last 11 bushels per acre.

The popular notion in regard to the effect of larvee on the straw is,
so far as I know, usually correct. This year, however, has been an ex-
ception, at least so far as southern and central Indiana is concerned.
As far north at least as La Fayette the larvee of the spring brood were
located just above the roots, and the straw did not break at the lower
joints, as is usually the case, but either fell or was blown over from the
roots, the culm usually being uninjured elsewhere. I observed this to
a very limited extent at Oxford, Indiana, in 1881. In fields about La
Porte, in the northern part of the State, none of this lower attack of
the plant was noticed, the larve and later the puparia being invariably
found just above some of the lower joints. Mr. James Fletcher, Do-
minion entomologist of Canada, reported at the meeting of the En-
tomological Club of the American Association for the Advancement
of Science at Indianapolis that the wheat about Ottawa, Canada, had
this year suffered from the attacks of larve of the spring brood in pre-
cisely the same manner as I had observed at La Fayette and south-
ward. Quite a percentage of the pupz in the fields about La Porte
were located so high up the stem as to render it probable that they
would be carried away with thestraw. As yet I have not found a good
reason for this difference, but have a vague idea that the killing down
of the plants during the preceding March migbt have had something
to do with it, as this was less severe in the northern part of the State.

THE EFEECT OF THE WEATHER ON THE DEVELOPMENT OF THE FALL BROOD.

It is quite probable that some autumns are more favorable for the development of
the insect than others, but just what the favorable influences are is not well under-
stood. Mr. Ratliff, at Richmond, saw an adult emerge from the pupa on October 16;
the wheat which it infested appeared above ground on September4. Between these

76

two dates, Mr. Ratlifi’s notes give the following record of minimum temperatures
through which the insect must have necessarily passed.

September 23: (EtOst)) eek ee ee ne ec ee cos Pat as oie er ee 26°
October 6. Clighteinost) Joos wean ate osc e scene ocae Bere eee 26°
October Tiidichtarost)--ss so. nc ce ane eisai ne ae Sere 34°
October 12s (light trost) 2s 2.8 os. Bs Sa re ae eee ote oe eee 26°
October J4-(heawy trost) 6.22.05 seeder bcs. e See Secs ce eee eee eee pAe
Octoberd db: Gros) soe Bake swish cee oe eee woke ose ae eee ee eee 26°
October 6: (ieht frost) sa. se ee oe eee eee eee ee eee 29°

Rains on September 11, 26, October 19. Total precipitation during September and
October, 2.50 inches.

At La Fayette, the same year, I found adults ovipositing on November 38, but of the
origin of these flies of course nothing wasknown. The temperature through which
these must have passed, supposing the eggs from which they evolved were deposited
after September 1, was as follows:

Min. temp.
Neptember 23 215 Sane: ea westemenseins eisle seals in seeto ee eee ee eeeets 39°
Septentberi24 (Grst frOst) eer nos -vetaete tee ne ate a eee ere 29°
October WL .cs set oSases aN Se renee tes re eee eee aoe
October 2 (fost) -s22625 4 aes c Sass eee pe ee eee eee een Ze
October 14*Grost)\ esse eee ee ee peas RE Pea ee Bar Bier aU ae SB)
October.15' Ghrost) =: sss Sate ae eos We Soke mele lee ae ee ee eee 31°
Ootober lO! His o ose care aie eee re eat ore oe es ee eee ete ree eee 38°
October: l9CErost) a. 2 oF Se oe eres cee oe ee nie Santee etna a= eee 31°
October-20: (high tsnows) isos: Bes sees eee eee oe io ase e tree 37°
October leis. ssusiee os ea ae ee see ee eee eee eee agie
October Vrs as eee Ss a ae ee i cee ce ee 21°
October 25 (frost) o.22 i Sek eee eee en ae Breen ee eee ee eee CRS
October: 26 (GOst) ate os Se RE es Sen a neat eran Se ae ee ese Py
October Qe (rost) igs foe e eee Ae eee eee eee ea ay oe LO
October:28' (frost) cu eek Sa ER ae ee ay ee ete Peepers 28°
OctoberiQQat sad io Ge yes ae Re ee 2 ee hee een har aan ee ee ae eee 33°
October S0s(fbOst) gases 8 a cye crepe ape Ne aera et ce epee eae ge 19°
October Gls se cctools aloe os eee oe be ioe eile Sa a ee ote eter 28°
INoyem ber 1 GrOst)) 25 Sess ee eae ae a aise ee eo eR ree 28°
November 2(frost) scons. oe soe ee Peo ia tA ee eos nase ie ee CeO
Nowvembor 3: (frost) soho ts ede Seow nee arse shoe omer 32°

Rains on September 7, 13, 14, 22, 27, 28, 29, 30, October 3, 9, 10, 12,
23. Total rainfall, 4.64 inches.

From this it will be observed that the adult flles may emerge and
Oviposit under what we suppose to be very adverse circumstances. To
what extent the eggs and young larve are able to withstand such
weather I have no facilities at present for demonstrating. The major
portion of the small brood of flies, however, emerge during a more
favorable period, and for meteorological aid against these we can only
look to the dry, hot weather of July and August, though to the south
a portion of September might be included. But the straggling indi-
viduals, which, as I have proved, may originate from stubble, volunteer,
or even early sown grain, and which I myself can find no satisfactory
reason for not considering either the retarded or accelerated individuals
of either one or the other or both broods, have it in their power to repro-
duce a considerable progeny, which, though of themselves not a serious

(i

menace to the crop, yet, added to that of the remainder of the brood,
greatly increase the probabilities of serious damage. For thesealong,
mild autumn, extending into December, would appear to be exceedingly
favorable, as it would enable their progeny to enter winter in a com-
paratively hardy state, and probably produce late appearing larve
the following year simultaneously with or but little in advance of the
progeny of the earlier appearing adults of spring. In other words, the
one winters as advanced puparia or unemerged adults, the other as ad-
vanced larve or newly formed puparia. It thus appears that while the
autumn usually has little effect on the major portion of the fall brood,
a mild October and November may emphasize the destructiveness of
the pest. Sofar as observed by me, a damp spring, even though a
cold one, is also favorable to the development of the insect, while dry,
hot summers are as unfavorable, and cause serious mortality to the
earlier stages of the fall brood of adults.

PREVENTIVE MEASURES.

These may be noticed as follows: Sowing at the proper time; burn-
ing the stubble; rotation of crops; sowing long, narrow plats in late
Summer as baits; applying quick-acting fertilizers to seriously infested
fields in the fall in order to encourage attacked plants to throw up fresh
tillers, and to increase the vigor of these that they may make sufficient
growth to withstand the winter. :

None of the measures are original with me, and in fact the most of
them are as old as the history of the species itself. There is certainly
much to be gained by the farmer in timing his sowing so as to avoid
the larger part of the fall injury, and if all farmers of a neighborhood
would sow about the same time even a serious outbreak would be so
diffused as to lessen its injury.

The burning of the stubble after harvest, when it is practical to do
so, is usually recommended by the majority of writers. The plan is
criticised by some authors on the plea that the parasites are also de-
stroyed, which, if allowed to continue, would themselves overcome the
fly. This idea has always appeared to me to be both theoretically and
practically wrong. If only the normal number of wheat plants allowed
by nature to spring up under a perfectly natural environment were pro-
duced, then the theory would be correct, because nature would then be
working out her plans from the beginning. As the facts exist hundreds
of thousands of plants are produced where nature intended but one.
Her domain is invaded and her law defied at the beginning. The Hes-
sian Fly is itself a parasite, the wheat plant being its host, and what we
term its parasites are practically only secondaries. In the Hessian Fly
nature has an efficient servant in controlling the wheat plant, and the
parasites of the former seem to be on guard to see that the duty is not
overdone. Now we outrage nature and expect that she will uphold us

by destroying these servants and permitting the indignity to go on.

78

With this state of affairs the American farmer has found that the Hes.
sian Fly will be overcome by its parasites only temporarily, and then at
the expense of a larger per cent of at least one crop. By burning the
stubble we destroy all of the pest and also numerous other enemies
which are to be found in the fields at the time. The present season,
however, many of the flaxseeds were so situated that it is doubtful if
enough heat would have reached them to have destroyed them.

In a rotation of crop the adults are obliged to travel about in seareh
of the fields, and there is a greater chance of their being destroyed while
thus engaged. This, however, has its exceptions, as we observed at New
Castle, about 30 miles northwest of Richmond, Indiana, on November 17,
1888. The whole field had been sown in standing corn, a portion of it
about the 5th of September and the remainder considerably later. The
early sown portion had been seriously attacked and at least 85 per cent
destroyed; the later sown portion was only slightly injured, as was late
sown wheat generally in the community. Here at the Indiana Experi-
ment Station the plan of rotation is as follows: Corn one year, followed
by oats one year, wheat one year, clover and grass two years. The
wheat fields are never seriously affected by the ravages of the Hessian
Fly.

Sowing narrow strips abouf the fields, early in the fall, as decoys, was
long ago strongly advocated by Dr. Fitch, but the advice has been, so
far as I have observed, totally ignored by the farmer. While it is
hardly possible to thus entrap the major part of the fall brood of larve,
it is certainly possible to entice to these plats the stragglers and inter-
lopers, which we have shown to be capable of considerable injury. In
this way the farmer can, in a measure, continue the influences of sum-
mer and winter in sharply separating and defining the two broods. In
other words, while he can not eradicate the pest in this way, he can
weaken its power to commit serious injury. It is very doubtful if the

volunteer wheat, springing up after the wheat has been plowed, canbe |

used as decoys, and if allowed to stand until the date of sowing the
fields, these volunteer plants should, by all means, be plowed under
as deeply as practieable, or grazed off by pasturing. Simply killing
the plants will not do, as has been illustrated by the experience of Mr.
Oliphant, previously cited, and by the observations of Professor Forbes
in Illinois.* If volunteer wheat is allowed to stand at all,it should not
be for over a fortnight. The proper time for sowing these decoys will
probably vary with the latitude. For northern Indiana they should be
sown during the latter part of August, and in the southern part of the
State not later than the first week in September. To the north and
south of this I have, as previously stated, no definite information as
to the date of appearance of the fall brood of flies, and hence can not
undertake to settle the date of sowing. These decoys should not be
permitted to stand over four weeks at the farthest, and should be plowed

———

* Bulletin 3, State Ent., Ill., p. 48, 1887.

19

very soon after the crop is sown, turning the infested plants under and
thoroughly covering them. Simple cultivation, whereby the plants
are only killed, would probably only destroy a portion of the insects,
the full-grown larve very likely going through the remainder of their
transformations.

The application of fertilizers is, I believe, here in this State confined
to the poorer soils, and there more for its general effect on the crops
than as against the effects of insects. The idea in late sowing is to
retard the plants so that they do not appear until after the greater part
of the fall brood of flies have appeared and died, then to overcome
the effect of this delay by aiding the plants to make the greatest possi-
ble growth before winter closes in, which will the better enable them to
withstand its rigors. In this direction, it would seem that the applica-
tion of proper commercial fertilizers would pay by the effect upon the
growing plants, even though the land itself was not in actual want of
such treatment. ‘The application to a field which has previously been
seriously damaged, with a view of encouraging the throwing out of
fresh tillers, is for practically the same purpose; andif thereis a tend-
ency to throw out the later shoots freely, if not too late in the season,
many may be enabled to secure sufficient vigor to sustain them until
spring. Whether it would be more profitable to plow and resow than
to try to secure a crop from the infested field by the aid of fertilizers
is, of course, a question which each farmer must decide for himself in
accordance with the time of year and extent of injury already done.

These measures are all of them practical and entail little if any
unusual expense. In fact, good farming presupposes that the most of
them will be carried out as among the essential elements of the business.
Where clover is to follow wheat it of course precludes the burning of
stubble or the destruction of volunteer plants, but it necessitates the
rotation of crop, and decoys can be sown and the seeding delayed. It
is hardly possible for a farmer to become so situated that he can not
carry out some of these measures, and if this were done generally, and
every year, the Hessian fly would, in all probability, become of so little
importance that it would cease to enter seriously into the problem of
successful wheat growing.

INDEX.

Abbot’s white pine worm, 60.
Acer saccharinum, 10.
A gallia siccifolia on beet, 16.
Agrotis, 46.

spp. injuring beets, 14.

Alfalfa crops injured by grasshoppers and army

worm, 44.
Allygus sp., on beet, 17.
Alnus, 42.
Aloes as remedy for scale insects, 36.
. Amarantus, 16,17.
Ambrosia, 14.
trifida, 54.
Amphipyra pyamidoides, 55.
Anisota rubicunda, 9.
Aonidia aurantii, 20.
Aphides found on beet, 17.
Aphidide, prevalence of, in Missouri, 48.
Aphidius, 48.
Aphis ambrosie, 54,
atriplicis, 17.
brassice, 54.
chrysanthemi?, 54.
cucumeris, 17.
mali, 54.
prunifolii, 54.
Apion sp. on beet, 16.
Apple leaf skeletonizer, 59.
Microlepidoptera injurious to, 51.
Arabis, 47.
Army worm damaging beets, 14.
attacking alfalfa crops, 44.
Arphia sordida, 59.

Arsenites of ammonia, experiments with, 55, 61.

Aspidiotus aurantii, 19, 26, 29.
citrinus, 29, 36. ¢
perniciosus, 26, 27, 28.

Athysanus (? sp.) on beet; 17.

Atriplex, 13, 15.

Australian lady-bird, 19.

Beetles injuring beet leaves, list of, 14.

beet roots, list of, 17.

Beet insects, list of, 13.

remedies against, 18.
Black chrysanthemum aphis, 54.
scab, 26, 28.

Blissus leucopterus on beet, 16.

Blister beetles on beets, 15.

Botis pesticata, 14.

Brown scale, 26.

Bruner, Lawrence, report by, 9.

25910—Bull. 23——6

|

|

Bugs on beet, 16.

Cacecia fervidana, 50.

Cecilius aurantiacus, 27.
California insects, notes on, 19, 37.
Caloptenus devastator, 44,
Camnula pellucida, 44.
Cankerworms, 46.

Cantharis nuttalli destructive to beets, 15.
-Ceanothus, 42, 43.

Centrinus penicillus on beet, 16.
perscitus on beet, 16.
Cercocarpus, 43.

Cereal crops, report on insects affecting, 63.

Chetocnema denticulata, 15.
pulicaria, 47.
Chalcid parasites of Clisiocampa, 43.
Characlea angulata, 55.
Chenopodium, 14, 15, 16, 17.
Cherry slug, 60.
Chinch bug, 16, 46.
Chrysanthemum Aphis, 54.
Chrysopa, 48.
Cidaria diversilineata, 55. x
Citrus trees destroyed by red scale, 19.
Clisiecampa californica, 48.
constricta, 42, 43.
erosa, 42.
thoracica, 42.
parasites of, 43.
Codling moth, 9.
Colaspis brunnea on beets, 15.
Coleoptera attacking beet leaves, 14.
beet roots, 17,
Colorado potato-beetle on beet, 16.
Conotrachelus, 47.
Copidryas gloveri, 14.
Coquillett, D. W., report by, 19.
Corn ear-worm, 9.
fiea-beetle, 47.
root-worm, 9, 60.

Corrosive sublimate as remedy for scaleinsects, 34. -

Cottony cushion scale, 19.
Crambus exsiccatus, 58.
Crategus, 42.
Cryptolechia nubeculosa, 50.

schlegerella, 50.
Cut-worms destructive to beets, 14.
Cydonia, 45.
Darapsa myron, 59d.
Datana angusii, 49.

ministra, 49, 50, &5, 60, 62.
81

82 :

Deilephila lineata feeding on beet leaves, 14.
Deltocephalus debilis, 58.

inimicus, 58.

sayi, 58.

melsheimeri, 58.

Desmia maculalis, 55.

Devastating locust, 44.

Devereaux, W. L., letter, 74.

Diabrotica, 55.

longicornis, 9, 60.
12-punctata, 14, 60.
vittata, 60.

Disonycha cervicalis, 15,
erenicollis, 15.
triangularis, 14.
xanthomelena, 15.

Dissosteira carolina, 14, 59.

Doryphora 10-lineata, 16, 55.

Dried Crambus, 58.

Echinocystis lobata, 16.

Emblethis arenarius, 16.

Empretia stimulea, 49, 55.

Epicerus imbricatus attacking beet, 15.

Epicauta cinerea, 15.

cinerea var. marginata, 15.
maculata, 15.
pennsylvanica, 15.

Epitrix cucumeris, 15.

Eragrostis major, 16.

Erythroneura sp. on beet, 17.

Euclea querceti, 48, 49.

Eurycreon rantalis destructive to beets, 14.

Euthoctha galeator on beet, 16.

Experiments for scale insects, 32.

False chinch bug on beet, 16.

Flea beetles, 15, 47.

Fluted scale insect, 19.

Forsythia, 45.

Fumigation for red scale, 20.

Garden web-worm injuring beets, 14.

Gas treatment for red scale, 20.

Gelechia intermediella? description of larva and

imago, 53.
roseosuffusella, 54.
rubensella, 54.

Geocoris bullatus on beet, 16.

Glue as remedy for scale insects, 35.

Gortyna nitela, 46.

Grain Aphis, 47.

Grasshoppers, 10, 44.

Green-striped maple worm, 10.

Hadena, 46.

Handmaid moth, 60, 62.

Helianthus, 14.

Heliothis armigera, 9, 46, 55.

Hemiptera attacking beet, 16, 17.

Hessian fly, numberand development of broods, 63.
effect of larve on plants, 73.
effect of weather on development of

fall brood, 76.
preventive measures against, 77.

Heteroptera attacking beet, 16.

Hibiscus militaris, 15.

Homoptera attacking beet, 16.

Hydrocyanic acid gas as remedy forred scale, 19,20.

Hyphbantria cunea, 50.

Icerya purchasi, 19. F
Ichneumonid parasites on Clisiocampa, 43.
Ichthyura inclusa on willows, 50.
Indiana, report of insects of, 63.
Insecticides, experiments with, 54.
Insects injurious in California, 19, 37.
Indiana, 63.
Iowa, 57.
Missouri, 45,
Nebraska, 9.
to beets, list of, 13.
Iowa, injurious insects of, 57. -
Jasside in grass, 58.
Jassus inimicus, 58.
June bugs attacking beets, 17.
Koebele, Albert, report by, 37. ~
Lachnosterna fusca attacking beet roots, 17.
Lagoa crispata, 49.
Leaf-hoppers attacking beet, 16, 17.
in grass, 58.
Lecanium hesperidum, 26.
olez, 26, 28, 29, 31.
Lepidium, 47.
Lepidoptera injurious to apple, 51.
beet, 13.
Leucania unipuncta damaging beets, 14.
Liburnia intertexta on beet, 17.
Ligyrus gibbosus destructive to sugar beet, 17.
Limacodes larve, 48.
scapha, 49.
Lime wash for scale insects, 32.
Locusts, 10. ;
Lophophanes inornatus, 44.
Lophyrns abbotii, 60.
Lygus pratensis on beet, 16.
Mamestra picta attacking beets, 13.
trifolii, attacking beets, 14.
Maple, soft, 9.
worm, 10.
Melanoplus atlanis, 14.
bivittatus, 14.
differentialis, 14, 59.
femur-rubrum, 14, 59.
spretus, 14.
Mercuric chloride as remedy for scale insects, 34.
Microlepidoptera injurious to apple, 51.
Missouri, injurious insects of, 45.
Montilia, 17.
Murtfeldt, Mary E., report by, 45.
Myzus persica, 54.
Nicholson, H. H., letter, 12.
Nebraska, injurious insects of, 9.
Nemobius vittatus, 59.
Nysius angustatus on beet, 16,
Opuntia engelmanni, 21.
Orgyia leucostigma on sycamore, 50.
Orthoptera injurious to beets, list of, 14,
Osborn, Herbert, report by, 57.
Papilis turnus, 59.
Parasa chloris, 48.
Pempelia hammondii, 59.
Penthina chionosema, description of larva and
imago, 51.
Pezotettix olivaceus, 14.
Pieris rape, 5d.
Piesma cinerea on beet, 16.

83

Pine worm, 60.
Phobetron pithecium, 49.
Phyllotreta sinuata, 47.
vittata, 47.
Phylloxera, experiments with resin compounds
on, 37.
Plant lice, 47.
Plochionus timidus, 50.
Plum curculio, 47.
Plusia brassice attacking beets, 14.
Potato stalk weevil, 60.
Proteopteryx spoliana, description of larva and
adult, 52,
Psychomorpha epimenis, 55.
Psylliodes convexior on leaves of beets, 15.
Purshia tridentata, 42.
Purslane bug, 16.
Quercus agrifolia, 42.
Red scale destructive to citrus trees, 19.
gas treatment for, 20.
Red spider, 26.
Remedies against beet insects, 18.
Resin compounds on phylloxera, 37.
wash for San José scale, 27.
Rhamnus californica, 43.
Rhus copalina, 49.
glabra, 49.
Saddle-back caterpillar, 49,
San José scale, 26.
resin wash for, 27.
Salt and lime wash, 32.
and sulphur wash, 32.
wash for scale insects, 31.
Saturnia io, 49.
Scale insects, methods for destroying, 19.
Schizoneura lanigera, 26, 54.
Selandria cerasi, 60.
Tose, 55.
Silpha opaca, occurrence in beet fields, 17.
Silver-top in grass, 58.
Siphonophora avene, 47, 54.
crategi, 54.

‘Siphonophora pisi, 17.

rose, 56.

rudbeckiz, 54.
Snout-beetles attacking beet, 15, 16.
Sodworm, 58.
Solanum nigrum, 15.

Spharagemon equale feeding on sugar-beet, 14.

Sphinx quinque-maculata, 55.
Spilosoma isabella injuring beet leaves, 13.
virginica injuring beet leaves, 13.

Steganoptycha sp., description of larva, 52.

description of imago, 53.
salicicolana, 53.
Stinging larve, 48.
Striped flea-beetles, 47.

Sugar beet culture, suggestions in regard to, 11.

insects, 11.
Sulphur wash for scaie insects, 32.
Systena frontalis, 15.
teniata var. blanda, 15.
Tachina flies parasitic on clisiocampa, 43.
Teeniocampa, 43.
Tetranychus telarius, 26.
Tomonotus sulphureus, 59.
Trapezonotus nebulosus, 16.
Trichobaris trinotatus, 60.
Trimerotropis latifasciata, 14.
Trioxys, 48.
Turf web-worm, 58.
Turnus butterfly, 59.
Vedalia cardinalis, 19.
Washes for scale insects, 27, 30, 31, 34.
experiments with, 3!.

Webster, F. M., report by, 63.
White grubs attacking beet roots, 17.

pine worm, 60.
Wickson, E. J., letter, 75.
Wire-worms on beets, 17.
Wisteria, 49.
Woolly Aphis, 26.
X. O. dust, experiments with, 54,
Yellow scale, 29.

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