“ yes By IE Art peers eee TNE rr a
ee Pe aura NEA oo EET Wn Heat iag aces eet iaelyebe? Se
atte . LESTE Ma Me BN Aa Tea ESE ofa te
Diese Ste ee ete Mae ad BEN a!
ee ae Diced 3 fon! pid
4 steal a sista Foote Fate TAPE te 3 Beton
elie! oie a Whee A ae!
MEE Te Tea ed Ta: Peay eee
ee See
br tedietycwt orm eee NO ween ers
were te Fore = Bef
ine Pet cs ae eyth Syanny ene ae 6 eS RT NEE PET NE Re ae
Wit ndeserer a Ao” ete fa ene Vee ude ce
oeyee
The E E fears pees eee Ihe emt KE
re eae CPA eM
Sta wa ate WW
there
Sen eet
Poteet ny setae ir) pera
ew eae ome EN PSM ne eae wenaectatal TO Ne
LEON ST NN Me at
eenccreccra:
on an de
Be Pag Mathes Near rye,
eee ert Sere Ne et ete
UNIVERSITY OF ILLHVOIS LIBRARY AT URBANA-CHAMPAIGN NATURAL HIST. SURVEY
?
; WAS
,
Digitized by the Internet Archive in 2011 with funding from University of Illinois Urbana-Champaign
http://www.archive.org/details/illinoistreesshr4776engl
GC 47 ’
EILLINOIS TREES AND SHRUBS:
THEIR Insect Enemies
ELE. t,. ENGLISH
oo AMTURA, SEGVERY SUM
eee) MAR 22 1999
LIBRARY
ILLINOIS NATURAL HISTORY SURVEY Circular 47
Sixth Printing
STATE OF ILLINOIS
DEPARTMENT OF REGISTRATION AND EDUCATION
BOARD OF NATURAL RESOURCES AND CONSERVATION
RonauD E. STACKLER, J.D., Chairman; THOMAS PaRK, Ph.D., Biology; L. L. Stoss,
Ph.D., Geology;
HERBERT S. GuTOWSKY, Ph.D., Chemistry; RoBpERT H. ANDERSON, B.S.C.E., Engineering; STANLEY K, SHaPIRO, Ph.D., Forestry; W. L. Everirr, E.E., Ph.D., Representing the President of the University of Illinois; JOHN C. GUYON, Ph.D., Representing the President of Southern Illinois University.
NATURAL HISTORY SURVEY DIVISION, Urbana, Illinois
SCIENTIFIC AND TECHNICAL STAFF GEORGE SPRUGEL, JR., Ph.D., Chief ALICE K. ADAMS, Secretary to the Chief
Section of Economic Entomology
WILLIAM H. LUCKMANN, Ph.D., Entomologist and Head
JAMES E. APPLEBY, Ph.D., Entomologist
WiuuIs N. Bruce, Ph.D., Entomologist
WayYNE L. Howe, Ph.D., Entomologist
RONALD H. MEYER, Ph.D., Entomologist
STEVENSON Moore, III, Ph.D., Entomologist, Ex- tension
EDWARD J. ARMBRUST, Ph.D., Associate Entomolo- gist
Marcos KoGANn, Ph.D., Associate Entomologist
JOSEPH V. Mappox, Ph.D., Associate Entomologist
ROBERT D. PauscH, Ph.D., Associate Entomologist
RALPH E. SECHRIEST, Ph.D., Associate Entomolo-
gist JOHN K. BOUSEMAN, M.S., Assistant Entomologist MICHAEL E. IRWIN, Ph.D., Assistant Entomologist DONALD E. KUHLMAN, Ph.D., Assistant Professor, Extension ROSCOE RANDELL, Ph.D., Assistant Professor, Extension WILLIAM G. RUESINK, Ph.D., Assistant Entomologist JAMES R. SANBORN, Ph.D., Assistant Entomologist DouGuas K. SELL, Ph.D., Assistant Entomologist C. RoBertT TAyuLor, Ph.D., Assistant Entomologist JOHN L. WEDBERG, Ph.D., Assistant Entomologist CLARENCE E. WHITE, B.S., Assistant Entomologist Kurt EK. ReEpBorG, M.S., Assistant Specialist JOHN F. WALT, M.S., Assistant Specialist, Extension JEAN G. WILSON, B.A., Supervisory Assistant LINDA ISENHOWER, Junior Professional Scientist STEPHEN ROBERTS, B.S., Junior Professional Scientist JOHN T. SHAW, B.S., Junior Professional Scientist DANIEL P. BARTELL, Ph.D., Research Associate BETTINA FRANCIS, Ph.D., Research Associate MARGARET ANDERSON, B.S., Research Assistant ROBERT J. BARNEY, B.S., Research Assistant Tzu-SUAN CHu, M.S., Research Assistant STEPHEN D. Cowan, B.S., Research Assistant MARION Farris, M.S., Research Assistant BONNIE IRWIN, M.S., Research Assistant JENNY KOGAN, M.S., Research Assistant Ros—E ANN MeEccout, B.S., Research Assistant BRIAN MELIN, B.S., Research Assistant CELIA SHIH, M.S., Research Assistant KatuHy Woop, M.S., Research Assistant JO ANN AUBLE, Technical Assistant LOWELL Davis, Technical Assistant CHARLES G. HELM, M.S., Technical Assistant Lu-PING LEE, M.S., Technical Assistant
Section of Botany and Plant Pathology
SEATS SUNN ERE, Ph.D., Plant Physiologist and
ea
EUGENE B. HIMELICK, Ph.D., Plant Pathologist
R. DAN NEELY, Ph.D., Plant Pathologist
D. F. SCHOENEWEISS, Ph.D., Plant Pathologist
J. LELAND CRANE, Ph.D., Associate Mycologist
WALTER HARTSTIRN, Ph.D., Assistant Plant Pathologist
BETTY S. NELSON, Junior Professional Scientist
GENE E. REID, Technical Assistant
Section of Aquatic Biology
D. HOMER Buck, Ph.D., Aquatic Biologist WILLIAM F. CHILDERS, Ph.D., Aquatic Biologist R. WELDON LARIMORE, Ph.D., Aquatic Biologist ROBERT C. HILTIBRAN, Ph.D., Biochemist ALLISON BRIGHAM, Ph.D., Assistant Aquatic
Biologist
WARREN U. BRIGHAM, Ph.D., Assistant Aquatic Biologist
RICHARD E. SPARKS, Ph.D., Assistant Aquatic Biologist
TED W. SToRCK, Ph.D., Assistant Aquatie Biologist JOHN TRANQUILLI, Ph.D., Assistant Aquatic Biologist MARY FRANCES BIAL, Junior Professional Scientist Cart M. THOMPSON, B.S., Junior Professional Scientist RICHARD J. BAuR, M.S., Research Associate DONALD W. DUFFORD, M.S., Research Associate JOHN M. MCNuRNEY, M.S., Research Associate HARRY W. BERGMANN, B.S., Research Assistant Kurt T. CLEMENT, B.S., Research Assistant LARRY W. CouTANT, M.S., Research Assistant HERBERT M. DREIER, M.S., Research Assistant MICHAEL A. FRAKES, M.S., Research Assistant THOMAS E. Hiuu, M.S., Research Assistant EARL THOMAS JOY, JR., M.S., Research Assistant RICHARD KOCHER, B.S., Research Assistant ROBERT MORAN, M.S., Research Assistant STEPHEN O. SWADENER, M.S., Research Assistant JANA LEE WAITE, M.S., Research Assistant STEPHEN W. WAITE, M.S., Research Assistant KATHRYN EWING, B.S., Technical Assistant SusAN Moore, Technical Assistant FLORENCE PARTENHEIMER, B.A., Technical Assistant WESLEY F. PorAk, B.S., Technical Assistant C. RUSSELL ROSE, Field Assistant
Section of Faunistic Surveys and Insect Identification
PuHiniep W. SMITH, Ph.D., Taxonomist and Head WALLACE E. LABERGE, Ph.D., Taxonomist
LEWIS J. STANNARD, JR., Ph.D., Taxonomist GEORGE L. GODFREY, Ph.D., Associate Taxonomist DONALD W. WEBB, M.S., Associate Taxonomist LARRY M. PaGeE, Ph.D., Assistant Taxonomist JOHN D. UNZICKER, Ph.D., Assistant Taxonomist BERNICE P. SWEENEY, Junior Professional Scientist Brooks M. Burr, M.S., Technical Assistant
Section of Wildlife Research
GLEN C. SANDERSON, Ph.D., Wildlife Specialist and Head
FRANK OC, BELLROSE, Sc.D., Wildlife Specialist
WILLIAM R. Epwarpbs, Ph.D., Wildlife Specialist
JEAN W. GRABER, Ph.D., Wildlife Specialist
RICHARD R. GRABER, Ph.D., Wildlife Specialist
HAROLD C. HANSON, Ph.D., Wildlife Specialist
(Continued on Inside Back Cover)
This paper is a contribution from the Section of Economic Entomology.
(724247 M—5-—76)
STATE OF ILLINOIS ® DEPARTMENT OF REGISTRATION AND EDUCATION
NATURAL HISTORY SURVEY DIVISION ® GEORGE SPRUGEL, JR., Chief
ILLINOIS TREES AND SHRUBS:
THEIR Insect Enemies
Ls brew Gls 8
ILLINOIS NATURAL HISTORY SURVEY
Cincelar 47 Printed by Authority of E ; Sixth Printing the State of Illinois GE, With Revisions SS (First Printing, 1958)
URBANA May, 1976
CONTENTS
About Insects 5 . Aphids or Plant Lice : Scale Insects Borers er Leaf Eaters .
Mites Gall- Producing “Insects and Mites . 2 About Trees and Shrubs and Their Pests 4
Ailanthus (Tree of Heaven) Ailanthus Webworm Cynthia Moth
Arborvitae Bagworm .
Arborvitae Leaf Miner Spruce Spider Mite Juniper Scale
Ash .
Red- Headed Ash Borer Ash Borer . Oystershell Scale :
Fall Webworm
Birch P Bronze Bir ch Borer Birch Skeletonizer
Boxelder a EA Boxelder Bug Boxelder Aphid. . : Eastern Tent Caterpillar .
Boxwood . : Boxwood Leaf Miner
Catalpa ws Catalpa Sphinx — sts Comstock Mealybug
Crabs and Hawthorns Yellow-Necked Caterpillar Woolly Hawthorn Aphid . European Red Mite San Jose Scale . ; Hawthorn Leaf Miner ,
Dogwood :
Dogwood Borer | Dogwood Scale .
Douglas Fir . .
Cooley Spruce Gall Aphid
Elm ..
Spring Cankerworm . White-Marked Tussock Moth . Fall Webworm . 5
Elm Leaf Beetle
European Elm Scale Seurfy Scale .
Putnam Scale .
Elm Leaf Aphid
Woolly Elm Aphid . . Elm Cockscomb Gall | Aphid « Elm Borer
WOOAMG. RAMON IW W Oo Ww WWwWNNNrF
Smaller European Elm Bark Beetle Banded Elm Lestloppes : Mites : . Euonymus.. . Euonymus Scale Hackberry
Hackberry Nipple Gall | Psyllid
Witches’-Broom Hickory . . Yellow-Necked Caterpillar Hickory Bark Beetle . . Hickory Gall Phylloxera . Hickory Horned Devil or Regal Moth . Juniper oe ‘ Juniper Scale Juniper Webworm . Juniper Bark Beetle Spruce Spider Mite Bagworm , Lilae : : Lilac Borer. cas Oystershell Scale Linden . : Elm Semone Locust Locust Bor er Bagworm Locust Mite Mimosa Webworm Maple : Cottony Maple Scale = Maple Bladder-Gall Mite Green-Striped Mapleworm .
Flatheaded ee Tree Borer
Aphids Pigeon Tremex Oak Borers : Periodical Cicada : May Beetles . Twig Pruner Oak Kermes Leaf Miners : Gall- anes Insects — Pine .. Sawflies — aude 4 White-Pine Weevil Pine Needle Scale Pine Bark Aphid. . . European Pine Shoot Moth . Nantucket Pine Moth Zimmerman Pine Moth
Poplar Poplar Borer Cottonwood Borer . . Poplar and Willow Borer
Carpenterworm . % . 59 Tuliptree Aphid . 66 Cottonwood Leaf Beetle . 60 Walnut... . 67 Poplar Tent Maker . 60 Walnut Caterpillar 5 Of Oystershell Scale . . 60 Black Walnut Curculio . 68 Privet .. . .60 Willow... on A . 68 Privet Thrips . 60 Willow Aphid . 68 Redbud . . 3 . 62 Bagworm . 68 Oystershell Scale ‘ <7 « 62 Borers . , . 68 Two-Spotted Spider Mite . . 62 Oystershell Scale . . 69 Spirea .. ie . 62 Yew (Taxus) , . 69 Spirea Aphid . 62 Black Vine Weevil . 69 Spruce . . - 62 Fletcher Scale Be vial Spruce Spider Mite .. . 62 Termites . Spill! Cooley Spruce Gall Aphid . . 64 Taxus Mealybug : . 73 Eastern Spruce Gall AU . . 64 Potential Insect Enemies 73 Spruce Bud Scale Sod Japanese Beetle 3 Spruce Budworm . . 65 Gypsy Moth. . 75 Pine Needle Scale . 65 Brown-Tail Moth ~ 5 (5 Sycamore . . . 65 About Insecticides : PG Sycamore Lace Bug . 65 About Spray Equipment Bagworm : 265 And Its Use as Borers . . 66 Index . 83 Tuliptree : . 66 Tuliptree Seale . 66
The kodachrome for the cover and most of the photographs for this
circular were taken by William E. Clark of the Illinois Natural History Sur- vey. Photographs from outside agencies are credited to those agencies.
TO USERS OF THIS CIRCULAR
Control measures are listed in the information sheets en- closed with this circular.
Printed by Authority State of Illinois Ch. 127 IRS, Par. 58.21
Ly y,
ii yy, Ly
oe DY
Trombone-type sprayer in use. This is an inexpensive sprayer that is con- venient for applying chemicals to limited numbers of shrubs and small trees.
ILLINOIS TREES AND SHRUBS:
THEIR Insect Enemies Le kes ENGELS: H
egardless of their size or cost, trees and shrubs used as orna-
mentals may be highly prized by their owners as sources of shade or beauty. An important aspect of the care of orna- mentals is the prevention of insect damage. Such plants may be severely damaged or even destroyed unless their owners have at least an elementary knowledge of insect pests and the ways in which they can be controlled. To provide help in the recognition of insect pests of trees and shrubs used as ornamentals and to suggest specific measures for control of these pests is the pur- pose of this circular.
Insects may damage trees and shrubs in many ways. A col- ony of ravenous caterpillars may strip the foliage from twigs and branches; hordes of aphids may suck the sap from new shoots and leaves, causing them to wilt or to grow abnormally; tiny scale insects may encrust branches and twigs, withdrawing enough food to kill plants outright; borers of many kinds may invade the bark and wood, seriously injuring or killing plants; more subtle but as serious is the damage caused by those insects that carry fungus or virus diseases.
ABOUT INSECTS
The first essential for effective control of insect pests is vigi- lance and an interest, which may be acquired, in looking for in- sects and signs of their damage. To detect the presence of insects before they cause serious damage to valuable trees and shrubs, one should carefully examine the plants at least once a week during the growing season. One should examine deciduous trees in winter, also, when scale insects on them may be seen more easily than when trees are in leaf.
The second essential is at least an elementary knowledge of insects and the ways they reproduce and grow. For example, one should know that while most kinds of insects lay eggs, some, like most of the aphids, give birth to living young. The eggs of insects are of various sizes, shapes, and colors; most of them are small in size and are not easily seen. They are laid singly or in clusters, hidden or in conspicuous places. With few exceptions,
2 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
insect eggs cause little or no damage, but many of the animals that hatch from the eggs are destructive.
Insects develop by metamorphosis, or change. The young of some kinds, boxelder bugs for example, look like the adults and reach maturity through a series of molts. The young of kinds that look unlike the adults are called larvae, grubs, cater- pillars, or worms. Eggs deposited by moths and butterflies pro- duce caterpillars that feed ravenously and molt several times before they reach maturity. The caterpillars change to pupae (latent stage) for transformation to moths or butterflies. The growth pattern of beetles is similar to that of moths and butter- flies. The young of beetles are often called grubs.
The following paragraphs contain information about sev- eral kinds of insects and the ways in which they feed.
Aphids or Plant Lice.—There is a species of aphid for al- most every species of plant. Aphids are sucking insects, fragile and awkward in appearance. They are most commonly green, pink, or black in color. Each aphid, only one-sixteenth to one- eighth inch long, is well equipped with a stout beak through which it draws great quantities of plant juice as it feeds from place to place on tender plant tissue. Heavy infestations of aphids usually produce a noticeable amount of honeydew, on which a sooty mold may grow. Aphids have an enormous repro- ductive capacity. Fortunately they have many natural enemies. Lady beetles, both larvae and adults, fatten themselves on aphids, and the larvae of tiny parasitic wasps feed within them.
Scale Insects.—Scale insects, small and inconspicuous, are likely to be overlooked until the branches of infested trees or shrubs are encrusted with them. They are sucking insects that live most of their lives under protective shells or scales. They may kill branches, limbs, and whole trees. Each insect is a mere sack of protoplasm with a threadlike beak thrust into the tissue of the plant it feeds upon. The female in most species of scale insects deposits eggs under her shell. The eggs produce crawlers that move away from the shell to find suitable feeding places. When the crawlers settle and begin to feed, each makes a shell for its own protection.
Borers.—Most borers that attack trees or shrubs are the larvae of beetles or moths. They hatch from eggs deposited on the bark of a tree or shrub. Soon after hatching, they bore into the wood of the plant. Healthy, vigorous trees are unattractive
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 3
to borers. Newly planted trees suffering from transplanting shock, and older trees growing in unfavorable places where little moisture or food is available, become attractive to the pests.
Leaf Eaters.—Severe damage by this group of pests is con- spicuous and easy to detect. In many cases, however, damage is not observed until serious defoliation has occurred. The prin- cipal leaf eaters are beetles and their larvae (grubs) and the larvae (caterpillars) of moths and sawflies. Damage by these pests is most likely to occur in the spring and early summer.
Mites.—Especially destructive to evergreens, these animals, barely visible to the naked eye, have great reproductive power and attack plants in large numbers. Some mites injure plants by rasping the leaf surfaces and removing the plant juices. Mites are not insects, although closely related to them.
Gall-Producing Insects and Mites.—Galls are abnormal] growths appearing as warts or bumps or attractive-looking balls on leaves and twigs. They are of many shapes and sizes, but each kind is characteristic of the animal that produces it. The production of some galls is stimulated by tiny mites too small to be seen with the naked eye. The production of others is stim- ulated by flies, aphids, and small wasps. A part of the life cycle of the gall-producing animal is spent inside the gall. Most galls do not cause serious damage to the plants on which they are found.
ABOUT TREES AND SHRUBS AND THEIR PESTS
In the discussion that follows, the host plants are arranged alphabetically. Each pest and the nature of its damage are briefly described; notes on the life history are given for each of the common and destructive pests.
AILANTHUS (TREE OF HEAVEN)
Ailanthus Webworm, Atteva aurea (Fitch), fig. 1—An oc- casional pest of ailanthus, or tree of heaven, the olive-brown cat- erpillar of this species feeds on the leaves under a thin web. Sometimes it attacks the petioles, causing the leaves to wilt.
ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
ee
Fig. 1—Ailanthus webworm: larvae. The olive-brown larvae or worms feed on the surfaces of leaves.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 5
Cynthia Moth, Samia cynthia (Drury).—The 3-inch, green caterpillar of this species has black dots and blue tubercles on its back. It feeds on the leaves of the tree of heaven. The adults are handsome brown moths, each with a wingspread of 6 to 8 inches. Sometimes caterpillars of this kind defoliate the trees on which they feed.
ARBORVITAE
Bagworm, Thyridopteryx ephemeraeformis (Haw.), fig. 2. — A widely distributed common pest, the larva of this species feeds ravenously on both evergreen and deciduous trees and
Fig. 2.— Bagworm: cases or bags constructed by larvae. Some of the bags shown here are almost filled with eggs laid by adult females of the bagworm. Eggs that survive the winter hatch in early summer. The ap- Remeprce of bags varies with the kinds of leaves from which the larvae have made them.
shrubs. Usually evergreens defoliated by bagworms die. Some of the spindle-shaped bags hanging from trees and shrubs dur- ing the winter contain eggs that produce a crop of worms in the following spring or summer. In southern Illinois, these eggs hatch usually during the latter part of May, in central Illinois during the first part of June, and in northern Illinois during the latter part of June. Newly hatched larvae are easily overlooked. After leaving the mcther bag, a small larva feeds on nearby foliage and begins to build a tough bag for itself with silken
6 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
thread and with bits of foliage taken from the host plant. Hence, bags on maples look different from those on arborvitae.
Each bag is enlarged to accommodate the rapidly growing larva inside and is carried everywhere the larva goes. The larva sticks its head out of the bag to feed, but quickly retreats when disturbed by birds or other enemies. By late summer, when the bag is 114 to 2 inches long, the larva matures, pupates, and transforms to the adult stage. The adult male, a black, fuzzy moth, emerges from its bag and flies about to mate with the wingless female, which remains in the bag while she lays 500 cr more eggs. After egg-laying, the female dies. The bagworm produces only one generation a year in Illinois.
Because only the male adult flies, infestations of bagworms are spread principally in the larval and egg stages. Small larvae suspended by their silken threads may be carried by the wind for considerable distances. Larger larvae often crawl from one plant to another in search of food. Larvae or bags containing eggs may be inadvertently transported by human beings.
Arborvitae Leaf Miner, Argyresthia thuiella (Pack.).— Feeding by the leaf-mining caterpillar of this species on the in- sides of needles causes the tips of arborvitae branches to turn whitish, tan, and brown. Less than one-fourth inch long, each greenish, red-tinged caterpillar comes from one of several eggs deposited on the leaves by a small moth in the spring. This pest may produce more than one generation in a season, and consid- erable damage may result from its feeding.
Spruce Spider Mite.—See under Spruce.
Juniper Scale, fig. 28.—See under Juniper.
ASH
Red-Headed Ash Borer, Neoclytus acuminatus (F.), fig. 3.— The short, white, round-headed grub of this species may girdle
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 7
small ash trees so severely that they break and fall. The grub tunnels in many directions, mainly in the sapwood. The adults are beetles, each about one-half inch long. Each has a reddish head, which accounts for the common name, and a V-shaped yel- low band across the wing covers. The female deposits eggs in crevices of bark in early summer. The young larva bores through the bark and feeds on the sapwood. It pupates near the surface of the wood. In June, the pupa transforms to an adult. which gnaws through the wood and bark and emerges.
Ash Borer, Podosesia syringae fraxini (Lug.), fig. 4.—This insect was once considered to be the same as the lilac borer, but it now appears to be different and to be limited to ash and moun-
Fig. 3.—Red-headed ash borer: A, adults; B, larva or grub; C, adult ready to emerge from its pupal case; D, furrows made by larvae in sapwood and holes through which adults emerged.
8 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 4.—Ash borer: adult (museum specimen). The female adult, a clear-winged moth, deposits eggs on the bark of a tree. Upon hatching, the young borers penetrate the bark and bore into the wood.
tain ash. The adult, a moth with transparent rear wings, depos- its eggs on the bark of the tree. The white larva eats through the bark, penetrating the harder wood to the center of some branches. In the fall, when nearly full grown, and almost an inch long, the borer works toward but not completely through the bark. Here it digs a sort of cell in which it passes the winter. Pupation occurs in the spring, and moths emerge in May and June.
Oystershell Seale, Lepidosaphes ulmi (L.), fig. 5.—The oys- tershell scale is inconspicuous, but it can be detected by careful examination of the limbs and branches it infests. Each scale protects itself by a light to dark brown oystershell-shaped cov- ering about one-eighth inch long. It feeds by sucking plant sap through a threadlike beak. Dense populations of this insect cause severe damage to many kinds of trees and shrubs.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 9
Fig. 5.—Oystershell scale: an infestation on a twig. A sapsucking in- sect is beneath each brownish shell. An infestation of this common and destructive insect may kill twigs and branches of lilac and other plants.
The overwintering, pearly white eggs of the oystershell scale hatch about the latter part of May, the time varying with weather and latitude. Each young scale, called a crawler, moves from beneath the mother shell and crawls about, usually toward younger wood. After a short time the crawler settles, loses its legs and antennae, and starts making a shell covering. The cov- ering is enlarged from time to time to accommodate the grow- ing insect. The male scale develops wings, escapes from the shell by squeezing under the edge, and roams freely for a mate. The female does not leave her shell for the mating event, but keeps sucking away at the tree sap. Under her shell she lays 80 to 100 eggs, which hatch the following spring.
Fall Webworm, Hyphantria cunea (Drury), fig. 6.—Un- sightly webs enclosing one or more branches of an ash in the early fall are signs of a ravenous colony of hairy caterpillars of the kind commonly known as the fall webworm. The adult fe- male of the fall webworm, a satiny white moth, emerges from one of the overwintering cocoons in early summer, mates, flies into a suitable tree, and deposits a patch of several hundred greenish eggs, usually on the under side of a leaf. On hatching, the young caterpillars move as a group to the upper sides of leaves and start feeding. At the same time, they start spinning
10 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
a web, which they enlarge to take in fresh foliage as needed. They do not consume the leaves entirely but skeletonize them to such an extent that they curl, dry up, and eventually die.
Fig. 6.—Fall webworm: tent and damage. The tent or webbing contains
a colony of pale green, or yellow, hairy caterpillars that feed on foliage of the host tree.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 11
Pale green or yellow in color, each with a dark stripe down the back and a yellow stripe along each side, the caterpillars do not leave the web until nearly full grown. At this time they move in many directions and feed on almost any green foliage available. When mature, they move to the ground to pupate under sheltering debris or just below the surface of the soil.
BIRCH
Bronze Birch Borer, Agrilus anzius Gory.—Widely distrib- uted and a serious pest of birch trees in the open, especially white birch, the three-fourths-inch long, white, flattened, and footless grub of this species attacks all parts of the birch above ground, burrowing under the bark and causing the bark to loosen and separate from the wood. The slender bronze beetle that develops from an overwintering grub cuts semicircular holes through the bark and emerges in early spring. The female lays white eggs in bark crevices. Larvae hatching from the eggs penetrate the bark, feed, and grow to develop another genera- tion.
Birch Skeletonizer, Bucculatrix canadensisella Chamb.— Unlike the bronze birch borer, which prefers trees in the open, the larva of this insect prefers woodland trees for its periodic attacks. Tiny caterpillars hatch from eggs placed singly on a leaf by the very small female moth, which is seldom seen. Each caterpillar bores directly into the leaf tissue, mines the leaf for a few weeks, and then skeletonizes the leaf on the under side be- fore dropping to the ground to pupate for the winter. The most extensive damage by this insect is likely to occur in August.
BOXELDER
Boxelder Bug, Leptocoris trivittatus (Say), fig. 7.—The adult form of this species is a black and red bug that feeds through a long, slender beak on the leaves and seed pods of the boxelder tree. It does little damage to the tree, but it creates a nuisance by congregating in great numbers about the tree and by migrating to nearby dwellings in the fall in search of winter
12 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fie. 7—Boxelder bug: adults. Shown here are boxelder bugs on the foundation of a building. The bugs, which are black and red in color, are of no consequence as pests of boxelder trees, but they are nuisances in and on buildings.
quarters. Fcllowing hibernation, the female lays small, red eggs in bark crevices. The red-bodied, black-legged nymphs that hatch from the eggs reach the adult stage through a series of molts.
Boxelder Aphid, Periphyllus negundinis (Thos.).—This is a pale green, hairy plant louse that occasionally develops in great numbers. An infestation by this aphid causes some injury to the infested tree and creates a nuisance by covering sidewalks and other objects beneath the tree with honeydew. Black eggs are deposited by the female on branches in the fall. The eggs hatch in the spring, and young aphids congregate on the new buds, from which they withdraw plant juices through their slen- der beaks. With the ability to develop several generations within a few weeks, these aphids can soon become abundant.
Eastern Tent Caterpillar, Malacosoma americanum (F.), fig. 8.—Although black cherry, chokecherry, and apple are favorite hosts, ravenous caterpillars of this species in the
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 13
Fig. 8.—Eastern tent caterpillar: larvae and damage to boxelder foliage. The female adult, a moth, lays a batch of eggs on a twig to produce a col- ony of hairy caterpillars with black heads.
14 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
spring construct tents in a wide variety of trees, including box- elder, elms, maples, and oaks. The black, hairy caterpillars hatch in March from an overwintering mass of eggs plastered to a twig in a brown band or collar. Caterpillars usually select a fork of a branch for the construction of a tent. They leave the tent to feed during the day but return at night. After feeding for 5 or 6 weeks, each caterpillar spins a cocoon on a tree trunk or in some other protected place, where it pupates. The adults, reddish-brown moths, emerge in early summer. This insect pro- duces only one generation a year. It occurs in abundance at in- tervals of about 10 years.
BOXWOOD
Boxwood Leaf Miner, Monarthropalpus buxi (Lab.).—Dam- age by this insect is indicated in early summer by small blotches on the leaves of boxwood. Later the blotches enlarge to blisters that cause the leaves to turn brown and to drop. The small yel- lowish-green maggots or larvae of this species feed on the tissue in the leaf during the summer and again in the spring before the orange-yellow midges develop and emerge from the pupae. The female deposits eggs in May for a new generation.
CATALPA
Catalpa Sphinx, Ceratomia catalpae (Bdv.), fig. 9—A rav- enous feeder consuming great quantities of catalpa foliage, the caterpillar of the sphinx moth may vary in color from pale yel- low with green markings to almost black. The caterpillar has a black, hornlike process at its rear end. When grown, the cater- pillar is about 3 inches long.
Emerging from an overwintering pupa in the soil, the fe- male of this moth mates and lays hundreds of eggs in white masses on the under sides of leaves. The young caterpillars feed in groups at first, but work individually later, consuming entire leaves.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES
Fig. 9.—Catalpa sphinx: larvae on a catalpa leaf. The handsome cater- pillars are ravenous feeders on catalpa foliage. About 3 inches long when grown, each caterpillar has a black hornlike process at the rear end.
16 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Comstock Mealybug, Pseudococcus comstocki (Kuw.).—An occasional pest of catalpa, the Comstock mealybug is likely to be found in cottony masses at the forks of tender shoots or at the bases of leaves. The male, which has wings, is seldom seen. The female, a wingless, slow-moving insect, when grown is about one-fourth inch long and elliptical in shape; she has a fringe of short, soft spines and is covered with ‘‘mealy,” white wax. A sucking insect like the aphid, the mealybug likewise secretes honeydew, which supports a sooty mold.
The mealybug’s yellow eggs, found in crevices of bark, are covered with a cottony mass of wax. When leaves appear on catalpa trees in spring, the eggs hatch, and the young mealy- bugs move to likely placés to feed and grow. This insect may produce several generations a year.
CRABS AND HAWTHORNS
Yellow-Necked Caterpillar, Datana ministra (Drury), fig. 10.—While seeming to prefer the foliage of apple and other fruit trees, the larva of this species finds nothing distasteful about the foliage of ornamental crabs and hawthorns wherever these plants are grown. Reddish in color when young, the ugly, fuzzy caterpillar has a yellow neck. It has a black head and four yel- low stripes along each side of its body. Caterpillars of this spe- cies feed ravenously in groups, but, when disturbed, they stop feeding and rear up at both ends. When fully grown, each cat- erpillar drops to the ground, burrows in a short way, and pu- pates. The adults, or moths, appear in early summer, and at about this time the female deposits eggs in clusters on the under sides of leaves.
Woolly Hawthorn Aphid, E'riosoma crataegi (Oest.), fig. 11. —Occurring in dense colonies on twigs and branches, the white, restless plant lice of this species are conspicuous. They may
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES
ae ae ©» : bo he Ny cw
yen
Fig. 10.—Yellow-necked caterpillar: larvae on small branch of haw- thorn. When disturbed, these caterpillars rear up at both ends. Reddish when young, each caterpillar has a black head and four yellow stripes along each side of its body. A grown caterpillar is easily recognized by its yellow neck and its black body, which is covered with long, white hairs.
‘Fig, 11.—Woolly hawthorn aphid: infestation on hawthorn twig. The aphids, which are white in color, have sucking mouthparts.
18 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
cause considerable damage to the hawthorn, distorting leaves and shoots by their removal of plant juices. The life history of this aphid is probably a complicated one and is not well known.
European Red Mite, Panonychus ulmi (Koch) .—Leaves of hawthorn or crab lacking a glossy, green appearance and hav- ing a somewhat blanched, or brown, dry look and a tendency to curl are signs of damage produced by hundreds of tiny red mites of this species feeding on both leaf surfaces. Brick red in color, the adults of the European red mite are scarcely the size of pin- heads. They have bristle-like hairs curving backward over their robust, globular bodies. The female deposits her eggs, which look like tiny cherries, in great numbers on both leaf surfaces. Development of the mite occurs through a series of molts. The white, discarded molt skins of a great number of young mites make infestations conspicuous. Rasping of the leaf surfaces and withdrawal of chlorophyll and plant juices cause serious damage to the plants infested.
San Jose Scale, Aspidiotus perniciosus Comst., fig. 12.— Probably the best known of the scale insects, San Jose scale is widely distributed and is a serious pest on many trees and shrubs. Heavy infestations encrust limbs and branches, causing them to die. Scraping an infested branch with a thumbnail or a knife squeezes the yellow juice from the saclike insects beneath the gray to black, circular shells, each about one-sixteenth inch
Fig. 12.—San Jose scale: infestation on bark of tree. A yellow saclike insect is beneath each circular shell shown here. The shells are each about one-sixteenth inch in diameter and gray to black in color.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 19
in diameter. The female overwinters as a partly grown insect and reaches maturity in early spring. After mating, she gives birth to living young: small, flat, yellow creatures, which crawl out from under the mother shell. When a crawler finds a suitable place, it settles down, inserts its threadlike beak into the bark tissue, loses its legs and antennae, and starts making a shell for its own protection. As the scale grows, its shell is enlarged and, following a series of molts, the scale reaches maturity. The fragile male scale develops wings and escapes from its protective shell to mate with a female, which does not leave its shell. The San Jose scale may produce several generations in a summer.
Fig. 13. — Hawthorn leaf miner: larva and damage to hawthorn leaf. The upper epidermis along one margin of the leaf is folded back to dis- close the white larva (arrow) and its excrement. Along the opposite mar- gin of the leaf is a dark blister, a sign of damage by the leaf miner.
20 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Hawthorn Leaf Miner, Profenusa canadensis (Marlatt), fig. 13.—Conspicuous dead areas that may include a fourth to half of a leaf at the tip or side indicate damage by the leaf miner. The adult is a sawfly, a beelike insect, that emerges from an over- wintering pupal case in the soil and deposits eggs in the tissue of unfolding leaves in May. The eggs, which may number 1 to 5 per leaf, produce larvae that mine the leaves. About 2 weeks after hatching, each larva makes a hole in the leaf and drops to the ground, where pupation and hibernation occur. This insect pro- duces one generation a year.
DOGWOOD
Dogwood Borer, Thamnosphecia scitula (Harr.).—The cat- erpillar of this species is white and it has a brown head. It is the larva of a clear-winged moth with a wingspread of less than an inch. Eggs deposited by the female moth on the bark of dogwood trees in May and June produce borers that eat through the bark. These borers feed just beneath the bark, often girdling limbs and small trees. The borers become full grown before winter, hibernate in their tunnels, and change to pupae in the spring.
Dogwood Scale, Chionaspis corni Cooley.—Usually kept un- der control by natural enemies, this scale occasionally builds up dense populations that give twigs and branches a whitish appear- ance. The female scale is somewhat pear shaped and about one- eighth inch long; the male scale is smaller and more slender and has three ridges on the upper side. Purple eggs carry the insect through the winter.
DOUGLAS FIR
Cooley Spruce Gall Aphid, Chermes cooleyi Gill., fig. 14.— Douglas fir is the intermediate host for this small aphid, which splotches the needles with cottony masses of wax that protect the aphid and her eggs. Some of the aphids developing from
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 21
Fig. 14.—Cooley spruce gall aphid: an infestation on Douglas fir. Each white splotch on the needles represents a cottony mass of wax that protects an aphid. Beneath the wax the female lays her eggs. Some of the insects developing from these eggs have wings; others do not. Those that have wings migrate to spruce, where they produce galls at the tips of branches.
these eggs have wings and they migrate to spruce, where they produce galls. No galls develop on Douglas fir.
ELM
Spring Cankerworm, Paleacrita vernata (Peck), fig. 15 and 16.—The spring cankerworm is a common pest of elms and per- havs the most important leaf eater that infests the American elm in Illinois. The caterpillar, or larva, is a dark green or black “measuring worm” that does not wait for the buds to unfold be- fore starting to feed. At first rather inconspicuous, the small caterpillar eats the tissue on one side of any leaf it feeds upon, but as it grows it punctures and later consumes all of the leaf except the large veins. By the time the caterpillar is 1 inch long, or full grown, it may be red, green, yellow, or black in color. It drops to the ground by means of a thread, burrows into the soil, and pupates. The adults emerge during warm spells in late
22 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
winter. The wingless female climbs a nearby tree and, after mat- ing, hides hundreds of eggs in crevices and under loose bark. These eggs hatch just as soon as the leaf buds begin to open in the spring. An elm may be partly or completely stripped of its foliage by spring cankerworms.
Fig. 15.—Elm foliage damaged by spring cankerworms. The dark green
to black “measuring worms” begin feeding before leaf buds are completely open.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 23
White-Marked Tussock Moth, Hemerocampa leucostigma (J. E. Smith), fig. 17—Second in importance to the spring can- kerworm as a leaf eater of American elm, this insect in its larval stage is mainly a pest of city shade trees. The showy caterpillar of the tussock moth begins feeding a little later in the spring than the cankerworm but may develop two generations in a year to make up for the late start. Its body is covered with tufts
Fig. 16.—Spring cankerworm: A, male adult; B, female adults (wing- less); C, eggs; D, larva; E, pupae. The larva is dark green, brown, or black. (Photographs from United States Department of Agriculture.)
of long white hairs. Two longer tufts of black hairs provide “horns” at the front, while a single black tuft “flags” the rear. When 5 or 6 weeks old, the caterpillar stops consuming leaves and spins a cocoon on the trunk or a limb of the tree on which it has been feeding, or on a fence or house. Here transformation takes place. From the cocoons emerge winged males and wing- less females. A wingless female, after emerging and mating, lays several hundred white eggs, all glued together in a clump,
24 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 17.—White-marked tussock moth: caterpillar, or larva, on leaf. This caterpillar is hairy; it has a red head, and its body is strikingly colored with yellow, black, red, and white.
on the empty cocoon. Newly hatched caterpillars skeletonize the leaves and consume all but the large veins.
Fall Webworm, fig. 6.—See under Ash.
Elm Leaf Beetle, Galerucella luteola (Miiller), fig. 18.—An- other ravenous leaf eater and a particular pest of Chinese elm, the larva or grub of the elm leaf beetle skeletonizes the leaves, causing them to dry out, curl, and drop prematurely. An ugly, almost black, spiny grub hatches from each of the yellow, spindle-shaped eggs placed by the female beetle in small groups
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES ES)
Fig. 18.—Elm leaf beetle: A, eggs; B, larva; C, pupa; D, adult. Both larva and adult feed on foliage. The eggs are yellow and spindle shaped; the larva is spiny and almost black; the adult, about one-fourth inch long, has a yellowish to green body and yellowish legs and antennae.
on the under sides of the leaves of an elm tree about the time the leaves become full grown. When through feeding, the grub drops or crawls to the ground near the base of the tree, pupates, and transforms to the adult stage to start another generation. The adults hibernate in barns, sheds, and dwellings, where, if present in large numbers, they sometimes become a nuisance. Each beetle is about one-fourth inch long; it has yellow legs and antennae and a yellowish to green body. It chews small holes in the foliage. The female beetle lays 400 to 800 eggs, which hatch in about a week.
European Elm Scale, Gossyparia spuria (Mod.), fig. 19.— Although inconspicuous, like other scale insects, the European elm scale occurs in dense populations and sucks great quantities of sap from any tree it infests. Some of the sap is secreted as honeydew, on which a sooty mold may grow.
The immature scale, which overwinters on a limb or branch or in a crotch of an elm, is about one-tenth inch long, oval, red- dish-brown in color, and has a white fringe. The male completes development in a white cocoon. The female changes little from the overwintering form. In early summer, she lays eggs on a limb or branch. Hatching in an hour or so, the young scales move in great numbers to the under sides of nearby leaves,
26 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 19.—Eurcpean elm scale: an infestation on an elm twig in spring. Fach scale has a reddish center and a white fringe.
where they settle and feed until late summer. Many migrate back to a limb or branch to hibernate, but some are lost when the leaves drop in autumn.
Scurfy Scale, Chionaspis furfura (Fitch), fig. 20.—Widely distributed and a pest of fruit and shade trees in addition to elm, the dirty white, pear-shaped scale of this species is about one- eighth inch long. Infestations of this scale are more conspicuous than the infestations of some other scales, especially when they are dense enough to give the infested bark an ugly appearance. Withdrawal of sap from a tree by an infestation of this scale reduces the vitality of the tree, kills branches and limbs, and sometimes, if the tree is young, deforms it.
The purple eggs, which carry the insect through the winter, begin hatching toward the last of May, giving rise to tiny purple crawlers that move away from the mother’s shell. The crawlers soon settle on the bark to feed and to make shells of their own. The scale covering of the female is broad, while that of the male is narrow and has three longitudinal ridges. This scale may produce two generations a year in the southern half of Illinois, but usually it produces only one generation a year in the northern half of the state.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES
Fig. 20.—Scurfy scale: an infestation on an elm twig. The scales are gray and somewhat pear shaped. The overwintering eggs under the shells are purplish. The hole made in one scale by an emerging parasite is indi- cated by an arrow.
Fig. 21.—Putnam scale: an infestation on an elm twig. The covering or shell of the female scale is almost circular and about one-sixteenth inch in diameter; that of the male is oblong. Near the center of each shell is a brick-red nipple that contrasts with the dark gray or black remainder of the shell. The scale insect beneath the shell is yellow.
28 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Putnam Scale, Aspidiotus ancylus (Putn.), fig. 21. Put- nam scale sometimes encrusts limbs and branches, causing them to die. Only about one-sixteenth inch in diameter, the female scale covering is almost circular and is cemented to the bark as a shell resembling an inverted saucer with a brick-red nipple that contrasts with the dark gray or black remainder of the shell. The shell of the male of the Putnam scale is oblong in shape.
Fig. 22.—Elm leaf aphid: infestation on under side of elm leaf. The aphids are greenish and of various sizes; some have wings ard some are wing less.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 29
The insect passes the winter as a yellow, partly grown scale beneath the shell. Development is completed in early spring, and, after mating, the female lays a few eggs a day. Egg laying and hatching extend over a period of 6 weeks or more. Some of the first-brood crawlers settle on the leaves of the elm, where de- velopment is completed; the second brood crawlers migrate back to the limbs or branches for the winter.
Elm Leaf Aphid, Myzocallis ulmifolt (Monell), fig. 22.— For the most part, this aphid is a nuisance pest because of the honeydew that drips on sidewalks and automobiles from the elm leaves on which the aphid feeds. Except for sooty mold that grows in the honeydew, there is no visible evidence of damage.
Both winged and wingless forms of the yellowish-green aphid, as well as white molt skins, are usually present on the under sides of elm leaves. Unlike many species of aphids, the elm leaf aphid does not migrate to another host.
Woolly Elm Aphid, E'riosoma americanum (Riley).—Curled elm leaves are signs of an infestation on the under sides of the leaves by the white, woolly, restless aphids of this species. In- festations are localized rather than general. This species over- winters in the egg stage. Eggs laid on bark hatch about the time elm leaves unfold; upon hatching, the aphids crawl to the leaves and begin to suck juices from the tissues. In June, the winged form migrates to shadbush, where it gives birth to a wingless form which, in time, produces another winged form that migrates back to elm to lay the overwintering eggs.
Elm Cockscomb Gall Aphid, Colopha ulmicola (Fitch), fig. 23.—On an elm leaf, a conspicuous, unsightly growth resembling a cock’s comb is a sign of this aphid. Production of each gall is stimulated by a wingless female aphid.
Galls produced by aphids of this species do little
damage. No control measure is recommended. Elm Borer, Saperda tridentata Oliv., fig. 24.—Escaping sap and small masses of wet, brown frass on the trunks and limbs of
30 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 23.—Elm cockscomb galls. Each gall contains many greenish aphids.
elms indicate the presence of larvae of this species. Probing an infested tree with a knife will disclose flat, shallow galleries run- ning in many directions and white, legless, segmented grubs. Each larva is about an inch long when full grown. The larva pu- pates in May. The adult is a gray beetle, about one-half inch
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 31
long, with three orange-colored stripes across each wing cover. The beetle cuts through the bark to escape. After mating, the female beetle deposits eggs on the bark of an elm tree. The young grubs that hatch from the eggs bore into the bark.
Smaller European Elm Bark Beetle, Scolytus multistriatus (Marsh.), fig. 25.—This bark beetle is the more important of two
Fig. 24.—Elm borer: A, larva; B, pupa; C, adult. The larva, or grub, is white and legless. The adult is a gray beetle about one-half inch long that has three orange-colored stripes on each wing cover (stripes only faintly visible in picture).
species that spread the deadly Dutch elm disease in Illinois. The other is the native elm bark beetle, Hylurgopinus rufipes (Eichh.), which is rarely found in Illinois.
The white, legless grub, or larva, of this beetle passes the winter under the bark of an elm tree. It pupates in early spring and transforms to the adult, a reddish-brown beetle, which drills a small hole through the bark to escape. Thousands of “shot holes” characterize the bark of heavily infested trees. If the beetle emerges from a tree infected with Dutch elm disease, it may carry spores of the disease fungus to a healthy tree, where inoculation takes place when the beetle feeds in the crotches of small branches. After feeding in the crotches of living elms, the beetle bores into recently cut elm wood or weak and dying tree trunks or branches. The female places white, spherical eggs along the edges of a gallery she constructs for this purpose. Small, white larvae that hatch from the eggs feed between the bark and wood, producing characteristic patterns with their
ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 25.—Smaller European elm bark beetle: larvae and galleries on the under side of elm bark. The adults, small, brown beetles, carry the Dutch elm disease fungus from diseased to healthy elms.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 33
mines. Emergence of beetles begins about the middle of May in Illinois and reaches a peak about the middle of June. A second brood of beetles which follows reaches a peak emergence in August.
Banded Elm Leafhopper, Scaphoideus luteolus Van D.— Rarely seen, this brown leafhopper, narrow and about one-fourth inch long, is reported to be the carrier of phloem necrosis, a seri- ous virus disease of American elms. The eggs of this insect over- winter on the bark of elms and hatch in early spring; the young hoppers, called nymphs, feed on new foliage, producing a brown area where the sap is withdrawn. The leafhoppers themselves cause little direct damage, but the virus they carry from diseased to healthy American elms is deadly to the trees.
Mites.—Several species of mites infest elms, but usually the damage they do is of little consequence. However, following the repeated use of certain insecticides on elm foliage, infestations of the two-spotted spider mite, Tetranychus telarius (L.), may become dense enough to bronze the leaves by their feeding and reduce the vitality of trees.
EVONYMUS
Euonymus Scale, Unaspis euonymi (Comst.), fig. 26.—This most important and destructive pest of euonymus is common also on bittersweet and pachysandra. The great number of white coverings of the males on the under sides of the leaves of in- fested plants immediately attracts attention and serves to help identify the pest. The female lives under a gray or brown shell, shaped somewhat like the shell of an oyster. In spring, the over- wintering female lays orange-yellow eggs, which produce crawlers that leave the mother shell and find a place to settle and grow on the host plant. This scale produces at least two genera- tions a year.
ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 26.—Euonymus scale: infestations on leaf, A, and twigs, B and Cc, of euonymus. Most of the scales shown are males, each of which has a white covering. The dark scales on twig B are females.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 35
HACKBERRY
Hackberry Nipple Gall Psyllid, Pachypsylla celtidismamma
(Riley) .— Conspicuous growths on the under sides of hackberry
leaves are signs of an infestation of this insect, sometimes called
a
Roe A Ye r) Pe Nie
-brooms on a hackberry tree. The brooms are very
Fig. 27.—Witches’ when no leaves are on the tree.
conspicuous in winter,
36 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
a jumping plant louse. Formation of each gall is stimulated by a tiny insect that feeds and lives inside the gall. The small, yel- lowish-brown adults pass the winter in bark crevices of trees or in the debris under trees. About the time leaf buds unfold, the female deposits eggs on the under sides of leaves. When the eggs hatch, each young insect crawls to the upper side of a leaf, settles down, and begins to feed through a short beak. The leaf tissue grows around the insect in characteristic fashion to form a gall. By September the insect completes its development and emerges as an adult through a slit it makes in the base of the gall. At that time of vear, insects of this species may make nuisances of themselves by flying into houses.
Witches’- Broom, fig. 27.—Abnormal growth that results in bunches or tufts of small twigs on the limbs and branches of hackberry is commonly called witches’-broom. Apparently the brooms do little harm to an affected tree, but they detract from its appearance. A tiny mite, Aceria snetsingeri Keifer, and a fungus, Sphaerotheca phyloptophila Kell. & Swingle, are asso- ciated with witches’-broom, but it is not known whether either or both stimulate the peculiar growth.
No control for witches’-broom on hackberry has been developed.
HICKORY
Yellow-Necked Caterpillar, fig. 10.—See under Crabs and Hawthorns.
Hickory Bark Beetle, Scolytus quadrispinosus Say.—Small emergence holes in the bark of the trunk and branches of a hick- ory tree are signs of an infestation by this species. The adults are dark brown beetles, each less than one-fourth inch long. After emerging from beneath the bark, each beetle feeds for a short time on young twigs, then bores through the bark of the same or a different tree, and constructs a gallery between the bark and the wood. Along the edges of the gallery, the female deposits eggs that give rise to white, legless grubs, which cause further and more extensive damage.
This species is especially injurious to hickories growing in parks. Heavily infested trees should be
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 37
cut down during the winter to destroy overwintering grubs. Healthy trees should be kept in a vigorous condition with appli- cations of water and fertilizer.
Hickory Gali Phylloxera, Phylloxera caryaccaulis Fitch.— Often overlooked until the affected twigs have died and the globular galls have been abandoned and have turned black, the greenish insects of this species may cause considerable or little injury to hickories, depending on the degree of infestation. After hatching from overwintering eggs, the young aphids stimulate the growth of galls on new twigs and prevent normal growth or kill the twigs beyond the galls. Each gall, which is at first green and may be one-half to three-fourths inch in di- ameter, is crowded on the inside with the greenish plant lice.
Hickory Horned Devil or Regal Moth, Citheronia regalis (F.).—The larval form of this insect is an occasional leaf eater of hickory as well as several other trees. It looks enough like the devil to be frightening. Approximately 5 inches long, this larg- est of our native caterpillars has a green body, a red head, and curving red horns just back of the head. In contrast, the adult insects are beautiful olive-green moths with a wing expanse of 4 to 6 inches.
Although a ravenous feeder, the hickory horned devil does not occur in sufficient numbers to justify spray- ing. Caterpillars on small trees can be collected and destroyed by hand.
JUNIPER
Juniper Scale, Diaspis carueli Targ., fig. 28.—This pest is common on various kinds of junipers, especially on plants used for landscaping. The covering of the female scale is nearly cir- cular and is dirty white in color. The covering of the male scale is white; it has a median ridge and is narrower and smaller than that of the female. Juniper scale may develop into a dense popu- lation on twigs and branches of junipers, causing them, or even entire plants, to die. In May, the overwintering female deposits eggs, which hatch in June.
38 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Juniper Webworm, Dichomeris marginella (F.), fig. 29.— The larva of this species is a light brown caterpillar only about one-half inch long. Several caterpillars web together and feed on juniper foliage, causing it to turn brown and die. Development of the caterpillars is completed in early summer. Pupation occurs
Fig. 28.—Juniper scale: an infestation on juniper. Dark red, sapsucking scale insects are under the gray or white shells on the surfaces of twigs.
in the webbing and debris; from each pupa a moth emerges. The female deposits eggs on foliage to produce another brood of cat- erpillars that pass through the winter. The caterpillars become active again in the spring.
Juniper Bark Beetle, Phloeosinus dentatus Say.—Several kinds of junipers are damaged by the adults of this species, dark brown, tubular beetles, each about one-sixteenth inch long. Be- ginning in early spring, the beetles feed in the crotches of small
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 39
branches, weakening many of them so that they bend down, break, and die.
Spruce Spider Mite.—See under Spruce.
Bagworm, fig. 2.—See under Arborvitae.
Fig. 29.—Juniper webworm: larva (inset) and web on damaged branch. A colony of the small, brown caterpillars of this insect usually kills an.in- fested branch.
40 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
LILAC
Lilac Borer, Podosesia syringae syringae (Harr.), fig. 30.— The larva of this insect is a major pest of lilac. The adults are moths that have transparent rear wings. Holes made in the bark of lilac by the grubs are likely to be numerous and are charac- terized by protruding sawdust, oozing sap, and, in the spring, by brown pupal cases at the entrances of emergence holes. Eggs deposited by the female in early summer on rough bark give rise to the white grubs that bore through the bark into the wood be- neath, where they feed and grow until winter brings their activi- ties to a halt.
Oystershell Scale, fig. 5—This is a major pest of lilac. See under Ash.
LINDEN
Elm Spanworm, Ennomos subsignarius (Hbn.).—The adult form of this species is sometimes called the snow-white linden moth. Both male and female are pure white. The larva or cater- pillar is a gray and brown looper with irregular yellow marks. Outbreaks of this insect occur at intervals of 10 to 20 years. The female moth deposits eggs in the summer on tree branches. The eggs do not hatch until the next spring. When outbreaks occur, the caterpillars are present in such numbers that they defoliate linden and several other kinds of trees.
LOCUST
Locust Borer, Megacyllene robiniae (Forst.).—Black locust is particularly susceptible to the larva of this insect. The larva is white, cylindrical, and up to 1 inch long. At first it mines the bark and sapwood of the locust, but later it bores into the heart of the tree, often causing so much damage that the trunk breaks. Growth, pupation, and transformation of the insect take place in the wood. The adults are beetles that emerge in autumn and feed on the pollen of goldenrod. Each is about three-fourths inch long, black, and has zig-zag yellow lines across the back.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 41
Fig. 30.—Lilac borer: A, damage to lilac branch; B, adult, a clear-
winged moth, on twig with frass at exit holes; C, larva in lilac branch (cross section). (Photographs A and B from Connecticut Agricultural Experi-
ment Station.)
42 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
ke See
Fig. 31.—Mimosa webworm: A, honey locust twig infested with mimosa webworm; B, “nest” in which the mimosa webworm larvae feed; C, mimosa webworm larva and honey locust leaflets.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 43
The female deposits eggs in the cracks and crevices of locust bark.
Bagworn, fig. 2.—This pest occurs on both black locust and honey locust. See under Arborvitae.
Locust Mite, Hotetranychus multidigituli (Ewing).— This mite, somewhat similar to other species of mites found on trees and shrubs, seems to be peculiar to honey locust. Just large enough to be visible to the naked eye, the mite varies in color from pale yellow to green; it has irregular dark areas near the edge of the body. The female deposits colorless spheroid eggs along the midrib of the under side of a leaflet. The base of the leaflet on the under side is the preferred feeding area. At first, heavily infested foliage appears stippled from above, but later it becomes blanched, and leaflets drop prematurely.
Mimosa Webworm, Homadaula anisocentra Meyrick, fig. 31.
The adults, mouse-gray moths, each with a wing expanse of only about one-half inch, emerge from overwintering pupae early in June. The female deposits eggs on the leaves of honey locust or mimosa. The small, pale gray to brown larvae web the leaves together to form a sort of nest, in which they skeletonize the leaflets. Badly damaged leaflets become dry and brown. In Illi- nois, such symptoms of webworm attack may appear by the latter part of July. When grown, each larva drops to the ground on a silken thread to pupate under ground cover. Second brood larvae produce conspicuous webbing in August. In the Wash- ington, D. C., area, the mimosa webworm produces a partial third generation each year.
MAPLE
Cottony Maple Scale, Pulvinaria’ innumerabilis (Rathv.), fig. 32.—A common, conspicuous, and injurious pest of soft ma-
44 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
ple, this species is found on several kinds of maples and a variety of other trees and shrubs. The infestations may be heavy enough to kill twigs, branches, limbs, and, occasionally, entire trees. The scale insects secrete great quantities of honeydew that drips
Fig. 32.—Cottony maple scale: infestation on soft maple. An infesta- tion of this insect can be identified easily by the masses of white wax, each of which contains hundreds of eggs.
on branches and foliage of infested trees, and on sidewalks and automobiles below. A sooty mold that sometimes grows in the honeydew causes branches and foliage to appear black.
The partly grown, brown, oval, female scale overwinters on a twig or branch. She grows rapidly in the spring and lays hun- dreds of eggs in a mass of cottony threads. Heavily infested branches appear as if decorated with popcorn. When the eggs hatch in June or July, young scales migrate to the leaves, where they settle and suck food from the leaf tissue. The males and females become mature in August; after mating, each female crawls back to a twig for the winter.
Fortunately, cottony maple scale has many natural enemies which help control it. However, at times sprays may be needed.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 45
Maple Bladder-Gall Mite, Vasates quadripedes (Shimer), fig. 33.—Unsightly green and reddish growths (galls) on the upper sides of the leaves of soft maple are signs of an infestation of the extremely small mites of this species. The mites overwinter on the bark of trees and in spring migrate to young leaves, where they stimulate the formation of galls, in each of which many mites live and feed. It is doubtful if galls associated with this species cause enough damage to large, vigorous trees to justify
Fig. 33. — Maple bladder galls on the upper side of a soft maple leaf. Growth of each gall is stimulated by extremely small mites, which live in the gall. This mite apparently causes little damage, except possibly to small trees. (Photograph from Michigan State University.)
46 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
spraying. Small trees, struggling for a start, may be benefited by spraying.
Green-Striped Mapleworm, Anisota rubicunda (F.).—An oc- casional pest of maple, the caterpillar of this species consumes entire leaves, and an infestation may defoliate a tree within a short time. The full-grown caterpillar is about 2 inches long. It is yellowish-green in color, has green stripes running lengthwise on its back, spines on its sides, and two horns on its thorax. The adults or moths of this species emerge in early spring from pupae in the soil; the female lays eggs on leaves of maples. The insect may produce two generations in a year.
Flatheaded Apple Tree Eorer, Chrysobothris femorata (Oliv.), fig. 34. — The larva of this common and widely distrib- uted insect attacks a great variety of shade trees and fruit trees.
Fig. 34.— Flatheaded apple tree borer: A, larva; B, adult, a gray or brown metallic-colored beetle about one-half inch long. (Photographs from United States Department of Agriculture.)
Almost any tree that is weakened by transplanting or dry weather or is wounded or damaged by sunscald may be invaded by this destructive borer. The adults are flat, metallic-colored beetles, each about one-half inch long. The female lays eggs in cracks and crevices in the bark of a tree; the young borers that emerge from these eggs have little trouble in boring through and tun-
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 47
neling under the bark. Often, trees are girdled by the white, leg- less, slender grubs with big flat heads. Feeding mainly in the sapwood at first, each grub mines deeper as it becomes larger and when grown it makes enough room at the end of a tunnel to spend the winter. Pupation and transformation take place in the early spring. At this time, an adult emerges through the tunnel made by a borer. The life cycle of the flatheaded apple tree borer is completed in a year.
Aphids.—Two species of aphids are pests of maples. They suck sap from the under sides of maple leaves and secrete enough honeydew, at times, to wet the sidewalks and streets under the trees. The Norway-maple aphid, Periphyllus lyropictus (Kess.), is a greenish insect that feeds along the veins on the under sides of the leaves of Norway maple and hard maple. The painted maple aphid, Drepanaphis acerifoliae (Thos.), is gray or black in the winged form and yellow in the wingless form. It is more common on soft maple than on other maples. Aphids usually do not cause enough damage to large trees to justify the expense of spraying.
Pigeon Tremex, Tremex columba (L.).—Associated with diseased and dying maples and many other kinds of trees, the pigeon tremex may be erroneously blamed as a serious tree pest. Each almost 2 inches long and with a reddish head and thorax, the adults are wasplike sawflies that bore holes in the trunk of a tree; there the female deposits eggs which hatch into grubs that live in the infested tree until development and transformation are completed.
A slender parasitic wasp belonging to the great family of parasites, the Ichneumonidae, probably does more to control the pigeon tremex than could be done with all sorts of in- secticides. With her ovipositor, a long threadlike appendage at the end of her abdomen, the female of this wasp, with uncanny precision, drills into a tremex tunnel and deposits an egg which produces a larva that attaches itself to the tremex grub and kills it.
No insecticide treatment is recommended for the pigeon tremex. Trees infested by the tremex probably should be cut down and removed because they are dying from other causes.
48 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
OAK
Borers.—Like other trees when weakened by transplanting shock, dry weather, or poor environment, oaks may be attacked by several species of borers. The flatheaded apple tree borer (see under Maple) and the carpenterworm (see under Poplar) are common pests of oaks.
Periodical Cicada, Magicicada septendecim (L.), fig. 35.— The female of the periodical cicada, which seems to prefer the terminal twigs of oaks for laying eggs, causes damage by tearing the bark and wood where she thrusts eggs into a twig. The dam- age resulting from many egg deposits in a twig causes it to die, and possibly to break off. Tiny nymphs hatch from the eggs, drop to the ground, burrow into the soil, and subsist for a 13- or 17-year period on the plant juices they can obtain from roots. The nymphs emerge from the ground in early summer, attach themselves to nearby objects, and molt to become adults. Both male and female are black and robust; they have reddish eyes, legs, and wing veins. With strident song, the males announce the presence of cicadas in great swarms at intervals of 13 or 17 years.
May Beetles, Phyllophaga spp.—The adults of many species of Phyllophaga (May beetles or June bugs) feed on the foliage of oaks and other trees, sometimes in such numbers that they defoliate small trees. These adults, which feed at night, are at- tracted to lights. Most of the beetles are solid brown in color and are one-half to three-fourths inch long. Eggs deposited by the female in the soil produce larvae, white grubs, that feed on the roots of grasses and other plants. Most May beetles have a 3-year life cycle.
Twig Pruner, Elaphidion villosum (F.).—Although not a major pest, the larva of this species when present in considerable numbers may litter a yard in late summer with twigs from oaks, elms, hickories, maples, and other trees. A clever animal, the larva tunnels around a twig under the bark, cutting into the twig to such an extent that it is easily broken off in the wind. Having burrowed farther toward the tip of the twig, the pruner falls with
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 49
Fig. 35.—Periodical cicada: A, adults on trunk of tree; B, punctures made in twig by adult female in laying eggs; C, eggs in tissue of twig. Dam- age to oaks is very conspicuous following an outbreak of the cicada.
50 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
the twig to the ground, where transformation occurs. The adult is a rather slender, brown beetle, about three-fourths inch long, that emerges from the pupa. The female lays eggs in twigs in early summer.
Oak Kermes, Kermes pubescens Bogue, fig. 36.—Of most im- portance on bur oak, but sometimes found on chinquapin, white oaks, and red oaks, the oak kermes is closely related to the scale
Fig. 36.—Oak kermes: an infestation of this almost spherical scalelike insect at the base of a new shoot.
insects. After wintering on the bark of twigs and branches, the oak kermes migrates to a growing shoot. Where numerous indi- viduals cluster around shoots and on the under sides of the leaves, they distort and kill the new growth. The full-grown female kermes is about one-eighth inch in diameter, almost spherical, light brown in color, and covered with very fine fuzz. The male produces a tiny white cocoon, in which it develops. In the spring, each female lays several hundred light brown eggs under her Shell. In June, the reddish-brown crawlers that emerge from the eggs leave the mother shell to find a suitable place for feed- ing.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 51
Leaf Miners, fig. 37.—Leaf miners, larvae of tiny moths, flies, sawflies, and small beetles, feed between the upper and lower surfaces of the leaves of oaks and many other shade trees, where they produce serpentine mines and blotches. Usually the female places her eggs on leaf surfaces, and each young larva, soon after it is hatched, bores into the leaf and proceeds to tunnel in various directions. If a mined leaf is placed in front of a bright light before the mine has been abandoned, the small larva that did the damage can be seen between the two leaf surfaces.
Fig. 37Leaf miners: damage to oak leaves. Very small larvae of several species of insects “mine” the leaves of oaks and other trees and de- stroy the tissue between the upper and lower leaf surfaces.
5/4 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 38.—Oak galls of three types stimulated by small wasps belonging to the family Cynipidae: A, gouty oak gall; B, wool sower gall; C, oak apple gall. The abnormal growth of plant tissue is stimulated in some mysterious fashion by these insects in the early part of the growing season. Each gall contains one or more larval cells. The wasp larvae eventually transform to the winged form and abandon the galls.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 53
Gall-Producing Insects, fig. 38.—Galls appear on oak twigs in a variety of sizes and shapes that include irregular, bumpy, warty growths and smooth, attractive, spherical formations. These galls are not manifestations of a systemic disease and are no cause for alarm. One of the unattractive kinds, the gouty oak gall, fig. 38A, most often found on red oak, is produced by a small wasp belonging to the family Cynipidae. Individual cells, each inhabited by a larva of the wasp, make up the inside of the gall.
A woolly ball an inch or more in diameter, at first white but brown when older, is known as the wool sower gall, fig. 38B. Also produced by Cynipidae, this gall is not numerous enough to cause severe damage. The oak apple, fig. 38C, is another spheri- cal gall, green or brown in color, an inch or more in diameter, which sometimes occurs in clusters. The spongy mass inside each gall has a larval cell.
Damage to oaks by galls is rarely serious enough to justify spraying. Since galls provide protection for the insects inside, sprays applied after the galls develop are ineffective.
PINE
Sawflies, Neodiprion spp., fig. 39.—The larvae of sawflies are often seen as colonies of caterpillars feeding on pine needles. They are especially injurious to young pines, which may be killed by one defoliation. Each larva, about an inch long when grown, has a red, brown, or black head, and many larvae have rows of spots running lengthwise of their bodies. The insect overwinters in a brown pupal case in the debris under a tree. Each less than half an inch long, the seldom-seen, beelike adults emerge in the spring. The female deposits eggs in slits she makes in pine nee- dles. Although hard to see when first hatched, because of their small size, the sawfly larvae soon attract attention by the disap- pearance of needles required to meet their appetites. Sawflies may produce two generations a year.
54 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 39.—Red-headed pine sawfly: four larvae and a pupal case (arrow) on pine. Rows of black dots are conspicuous on the pale yellow larvae, which consume the needles of young pines and may cause serious damage to the trees. (Photograph from Pennsylvania State University.)
White-Pine Weevil, Pissodes strobi (Peck).—This pest pre- fers white pine, but it feeds upon Scotch and jack pines, also. Damage by the weevil is readily recognized by dead and dying terminal leaders of infested trees. The overwintering adults, each only about one-fourth inch long, feed on terminal twigs in the spring. At this time of year, the female deposits eggs on the terminal twigs. The larvae feed under the bark in the same gen- eral region, causing enough damage to kill the twigs.
Pine Needle Scale, Phenacaspis pinifoliae (Fitch), fig. 40.— Scales of this species appear as white specks along the needles of its favorite hosts, Austrian and Mugho pines, as well as other kinds of pines and some spruces. The purple insect under each shell sucks out sap and chlorophyll, reduces the vitality of the needles, and causes shedding of needles. Reddish eggs, which
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES
Fig. 40.—Pine needle scale: infestation on pine. Scales appear as white specks along the needles. (Photograph from Connecticut Agricultural Ex- periment Station.)
56 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
overwinter under the shell of the female, hatch in the early sum- mer. Each nymph or crawler moves to a new place, settles after a few days, and inserts its beak into the leaf tissue to feed. It soon begins to make a shell. This species of scale produces two broods of crawlers during the summer.
Fig. 41.—Pine bark aphid: infestation on white pine. The aphids them- selves are inconspicuous, but an infestation is easily recognized by the splotches of cottony substance they produce.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES =i
Pine Bark Aphid, Pineus strobi (Htg.), fig. 41.—White patches of cottony substance on the trunks and limbs of pines make an infestation of this pest easy to recognize. The insect prefers white pine but sometimes feeds on Scotch and Austrian pines. Its feeding does little damage to large, thrifty trees but may weaken young trees.
The immature aphid, which overwinters under the “cotton,” matures in the early spring and lays yellowish eggs, which also are covered with “cotton.” These eggs hatch in June, producing both winged and wingless forms. The winged form apparently migrates to other pines. The wingless form remains where it was hatched and lays eggs which produce the overwintering nymphs.
European Pine Shoot Moth, Rhyacionia buoliana (Schiff.).— The black-headed, brown larvae of this species may cause serious damage to Mugho, red, and Scotch pines by boring into the shoots, causing them to turn brown and die. The partly grown, over- wintering larvae become active in the spring and bore into unin- fested shoots; pitch forms at the entrance holes they make. Pu- pation occurs in early summer, and the female moth, soon after emerging from her pupa, deposits eggs near the tips of twigs. Each young larva bores into the bases of needles to feed; feeding by the larva causes the needles to turn yellow. Later the larva bores into a shoot for the winter. Removal and destruction of infested shoots in winter may help control this pest.
Nantucket Pine Moth, Rhyacionia frustrana (Comst.), fig. 42.—-The small, yellowish larva of this insect is only about one- half inch long. It may kill many tips of red, jack, and other pines. The adults, reddish-brown moths, emerge in the spring from overwintering pupae. The female deposits flat, yellowish eggs on the needles and terminal leaf buds of pines. The larvae mine the needles at first but later bore down the centers of twigs. They construct delicate webs that enclose the affected needles and twigs. Larvae of the first two generations per year pupate in buds.
58 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 42.—Nantucket pine moth: damage to pine shoots by the small, yellowish larvae of this moth. Red pines and jack pines are favored by this pest.
Zimmerman Pine Moth, Dioryctria zimmermani (Grote) .— The light gray, reddish-yellow, or greenish larva of this species tunnels under the bark around limbs and branches of pine, espe- cially at the whorls, where it does serious damage. Presence of larvae usually can be recognized by the great quantity of pitch over the tunnels. Scotch and Austrian pines are particularly susceptible to this insect.
The maximum flight of the adults, which are nocturnal, dark gray moths, occurs about the middle of August, when the female deposits eggs on the bark of pine. The larvae usually work where bark is thin. Pupation occurs in the larval tunnels.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 59
POPLAR
The fast-growing poplars, Lombardy, Carolina, aspen, and cottonwood, are almost certain to be short-lived because of the ravages of borers. Some of these borers are discussed briefly be- low.
Poplar Borer, Saperda calcarata Say.—The white, cylindrical larva, which does the boring, and the adults, bluish-gray beetles, are each more than an inch long. Eggs deposited in slits in bark in the summer produce the borers that work under the bark and sapwood and into the heartwood of an infested tree. Frass or sawdust at the base of a tree indicates the presence of borers. Three years are required for the life cycle of this insect.
Cottonwood Borer, Plectrodera scalator (F.).—The adult form of this insect is a large beetle with long, black antennae. The female lays eggs in cavities dug in the bark. The eggs pro- duce white, deeply constricted grubs that when grown are up to 2 inches in length. These grubs, the tunnels of which are plugged with wood fibers, work near the bases of trees or even below ground. Badly infested trees may be easily blown over. Two years are required for the life cycle of this insect.
Poplar and Willow Borer, Sternochetus lapathi (L.).—The larva of this insect is a legless grub or borer, about one-half inch long, that bores into poplars and willows. The adults are black snout beetles or weevils. The borer feeds in the limbs and branches, as well as in the trunk, of the tree it infests. It prefers wood 2 or more years old.
Carpenterworm, Prionoxystus robiniae (Peck).—The larva of this insect is a pinkish, slightly flattened caterpillar, up to 214 inches long, that develops from an egg deposited in a bark crevice by a large, gray moth. The carpenterworm requires 3 years to complete development, during which time the larva mines and loosens the bark and drills large holes into the trunk of the infested tree. It may deform trees and branches.
60 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Cottonwood Leaf Beetle, Chrysomela scripta F.—The foliage of cottonwood and willow is often skeletonized by the dirty yellow larvae of this species. The overwintering form, a beetle about one-fourth inch long, has a black head and thorax and yellowish wing covers. In spring, it emerges from the debris about a tree. The female deposits masses of yellow eggs on the under sides of leaves. The larva eats the tissue of leaves, all but the veins, com- pletes development in 2 weeks or so, and, attached to a leaf, pu- pates with its head hanging downward. This insect provably has two broods a year.
Poplar Tent Maker, Jchthyura inclusa Hbn.—Silken tents enclosing a branch or twig of a poplar are signs of colonies of the black-mottled caterpillars that are the larvae of this insect. As the caterpillars grow, they take more and more leaves into the tent. The insect overwinters in the pupal stage. The female moth that emerges from an overwintering pupa deposits masses of eggs on leaves to produce caterpillars that feed in June. A second brood of caterpillars occurs in August.
Oystershell Scale, fig. 5—This is a common and destructive pest of cottonwood. See under Ash.
PRIVET
Privet Thrips, Dendrothrips crnatus (Jablon.).—This thrips in both adult and nymphal forms is a small, flat, elongate insect that feeds in great numbers on privet foliage, withdrawing the juices and chlorophyll. The adult thrips, dark brown and yellow, have wings. The nymph, almost colorless at first, becomes lemon yellow as it increases in size. Privet leaves affected by this insect become dotted and dirty with excrement and they fall prema- turely. Because this insect feeds at first on the under sides of leaves, it often goes unnoticed until the leaves have been severely damaged.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 61
REDBUD
Redbud Leafhopper, Erythroneura bistrata McAtee, fig. 43. —This is the most common of several species of leafhoppers that feed in great numbers on the foliage of redbud. With sucking mouthparts, the insects feed on the under sides of the leaves, withdrawing the plant juices and chlorophyll so that the leaves become blanched. The adult, about one-eighth inch long, is marked with red. The nymph, similar in shape but smaller, is whitish. Both forms are active; adults fly up in small clouds when disturbed. This insect has two or three generations a year.
Fig. 43.—A, leafhopper of the species Erythroneura bistrata, adult greatly enlarged; B, damage to redbud leaves by leafhoppers.
62 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Two-Spotted Spider Mite, Tetranychus telarius (L.).—The foliage of redbud trees is sometimes infested with great num- beis of green or yellowish mites of this species. The mites remove so much chlorophyll and juice from the foliage that the leaves be- come dry and drop prematurely. The overwintering female mites move to the leaves in early summer to feed and deposit trans- lucent, spherical eggs. Six-legged larvae hatch from the eggs in a few days. After the first molt, the mites have eight legs. Follow- ing two more feeding periods and molts, the mites become adult. The mites of various stages differ in size but are similar in ap- pearance. Males are slightly smaller than females, and their ab- domens are more pointed than those of females. There may be a number of generations of this mite during the summer.
Oystershell Seale, fig. 5—See under Ash.
SPIREA
Spirea Aphid, Aphis spiraecola Patch, fig. 44.—This green plant louse occurs nearly every spring in great numbers on the tender shoots of spirea. Eggs deposited on spirea in the fall give rise to mother aphids that produce living young in the spring. Wingless and winged forms may be present; the latter migrate to other host plants as the plant growth hardens. Quantities of sticky honeydew are produced by an infestation of this aphid.
SPRUCE
Spruce Spider Mite, Oligonychus ununguis (Jac.).—The spruce spider mite is small, but its dense populations can do a great deal of damage. It is one of the most troublesome pests of arborvitae, spruce, and juniper. It lives on the juices of these plants. When the sharp green color of the foliage begins to give way to gray, and later brown, it is too late to prevent some de- gree of damage, but prompt action may prevent serious damage or death of the plants.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 63
Overwintering eggs at the bases of the needles of infested plants produce tiny, light green mites in early spring. Through a series of molts the mites mature into larger, darker green, or almost black individuals, with spinelike hairs that curve back-
Fig. 44.—Spirea aphid: infestation of this green plant louse on a spirea shoot. After sucking sap from the shoots of spirea for a short time in spring, this aphid develops a winged form that migrates to other host plants.
ward over their robust bodies. The mites can be seen as moving specks on a white piece of paper or dish that has been held under infested branches struck sharply with the hand. This species has a number of generations in a season.
64 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Cooley Spruce Gall Aphid, Chermes cooleyi Gill.—Gall aphids of this species produce thick, elongate galls at the tips of twigs of Colorado blue spruce, Sitka spruce, and Engelmann spruce. The galls are so heavy that usually they cause the twigs to bend. In midsummer, the galls open and the aphids emerge. Some of the gall aphids develop wings. Gall aphids of the winged form migrate to Douglas fir, where the females lay eggs. The eggs and young gall aphids are covered with patches of cottony wax. No galls develop on Douglas fir.
Eastern Spruce Gall Aphid, Chermes abietis L.—Gall aphids of this species produce somewhat pineapple-shaped galls near the bases of spruce twigs. Sometimes these gall aphids cause severe damage to Norway spruce.
Spruce Bud Scale, Physokermes piceae (Schr.), fig. 45.—The mahogany-brown, globular scales of this species cluster at the
de
Fig. 45.—Spruce bud scale: infestation on spruce. The globular, ma- hogany-brown scales resemble spruce buds and are difficult to detect.
ENGLISH: [LLINOIS TREES. THEIR INSECT ENEMIES 65
buds and nodes of spruce. The overwintering female fills her shell, about one-eighth inch in diameter, with purple eggs in June. In central Illinois, the eggs hatch about the first of July. The flat, purple crawlers move away from their mother to settle in a new place.
Spruce Budworm, Choristoneura fumiferana (Clem.).—A destructive forest pest that sometimes attacks ornamental spruces, the larva of this species is a dark reddish-brown cater- pillar about 1 inch long when grown. It feeds on the opening buds and needles, tying them together with silk.
The overwintering caterpillar becomes active in the spring and completes development. The adults, dull gray moths, emerge from the pupal case in midsummer, when the female deposits masses of overlapping, greenish eggs on the needles.
Pine Needle Scale, fig. 40.—See under Pine.
SYCAMORE
Sycamore Lace Bug, Corythucha ciliata (Say), fig. 46.—This insect is probably the most common pest of sycamore. Both adults and nymphs feed on the under sides of the leaves in great numbers, withdrawing so much plant juice and chlorophyll that the foliage becomes pale and dry. The leaves become dirty with excrement. Both male and female are pretty insects; each is about one-eighth inch long and has a black body and almost transparent, lacelike wings held flat when at rest. By contrast, the black, spiny nymph is ugly.
The overwintering female becomes active in early spring and deposits eggs on the under sides of new leaves. The eggs hatch in a couple of weeks, and each nymph molts five times be- fore becoming an adult, 30 to 40 days later.
Bagworm, fig. 2.—This, the most common leaf eater on syca- more, is discussed under Arborvitae. Sprays applied in late summer after the larvae stop feeding, or during the win-
66 ILLINCIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 46.—Sycamore lace bug: adults. The bugs, which are black and have almost transparent wings, are shown congregated on the bark of a tree. They have sucking mouthparts and feed on the under sides of leaves. (Photograph from Connecticut Agricultural Experiment Station.)
ter, are ineffective. The worm infestation can be reduced by picking and burning the overwintering bags.
Borers.—Newly set sycamores, like most other newly set trees, are subject to attack by borers, especially the flatheaded apple tree borer, fig. 34.
TULIPTREE
Tuliptree Scale, Toumeyella liriodendri (Gmel.).—Oval, brown females of this species may be seen plastered on the bark of lower branches and twigs of the tuliptree in summer. Great quantities of honeydew drip from the scales. Inconspicuous over- wintering nymphs, also plastered on the bark, grow rapidly in the spring and early summer. The female reaches maturity in August and apparently gives birth to living young.
Tuliptree Aphid, Macrosiphum liriodendri (Monell).—This small, greenish aphid occurs in great numbers on the under sides of the leaves of the tuliptree. Honeydew, which is secreted
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 67
in large quantities by the aphids, makes the leaves sticky and drips on objects under the tree. Sooty mold often grows in the honeydew and causes the leaves and other objects it covers to appear black.
WALNUT
Walnut Caterpillar, Datana integerrima G. & R., fig. 47.— The larva of this species, a large, black caterpillar with gray
Fig. 47.—Walnut caterpillar: a colony of larvae. Walnut caterpillars, reddish when small, later have black bodies covered with white hair. They may completely strip the foliage from the trees they infest.
68 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
hairs, is the main leaf eater of walnut trees and, for some un- known reason, is attracted to isolated trees. It is very fond not only of walnut but of butternut, hickory, oak, honey locust, and willow; somet:mes it feeds on apple and other fruit trees. Each caterpillar develops through a series of molts from one of many eggs laid in masses on leaves of the host tree. An egg mass pro- duces a colony of caterpillars that may destroy the foliage on a whole limb before moving to fresh leaves. The colonies migrate downward on a limb or tree trunk, molt, and leave a clump of skins the size of a man’s fist. When grown and about 2 inches long, the caterpillars leave the infested tree and dig into the soil. There they pass the winter in the pupal stage. The adults, brownish moths, emerge in early summer. The female flies into one of the preferred kinds of trees, where she deposits eggs.
Black Walnut Curculio, Conotrachelus retentus (Say) —This reddish-brown weevil feeds on tender shoots and foliage of wal- nut for a while in the spring. The adult female makes, in the young walnuts, crescent-shaped cuts in which she deposits eggs. Feeding of the larvae that hatch causes the nuts to drop when only about half grown.
Fortunately this walnut pest is attacked by several parasites, which help keep it under control.
WILLOW
Willow Aphid, Clavigerus smithiae (Monell), fig. 48.—This rather large, dusky aphid may infest twigs and leaves of willows during the summer. Unlike many kinds of aphids, this one is restless, easily disturbed, and rapid in its movements. Both winged and wingless forms may be present on an infested tree. By withdrawing juices from leaves, this aphid may cause the leaves to wilt and drop.
Bagworn, fig. 2.—See under Arborvitae.
Borers.—See under Pcplar.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 69
Fig. 48.—Willow aphid: an infestation of the wingless form on a twig. This dusky, relatively large aphid withdraws juices from leaves, causing them to wilt and drop.
Ovstershell Scale, fig. 5—See under Ash.
YEW (TAXUS)
Black Vine Weevil, Brachyrhinus sulcatus (F.), fig. 49.— Rapid dying of yew—dying similar to that caused by transplant-
70 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
ing shock—may indicate that the roots have been eaten by the white, legless, crescent-shaped grubs of the black vine weevil. The grubs feed on plant roots from late summer until late spring. Development and transformation of this insect take place in the soil, and the adult weevils make their way to the surface about the first of June. The adults are seldom observed, as they hide during most of the daylight hours and feed sparingly, mainly at night, on the foliage toward the center of the plant. The female does not deposit her eggs on a plant, as many insects do, but simply drops them on the ground. This insect has only one gen- eration a year. A long preoviposition period makes it possible to time a control spray to kill all adults after they have emerged from the soil and before they have dropped eggs.
From southern to northern Illinois, this period may vary from June 15 to July 15. The spray should be applied to plants to the point of drenching them.
Fig. 49.—Black vine weevil: larvae and damage to small yews. The adult, a black snout beetle, is seldom seen.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 71
Fletcher Scale, Lecanium fletcheri Ckll., fig. 50.—This is a soft scale, usually occurring sparsely on yew but sometimes as heavy infestations that cause serious damage. The overwinter-
Fig. 50.—Fletcher scale: infestation on yew. The overwintering females are pale yellow to brown in color and globular in shape.
ing female, pale yellow to brown in color and globular in shape, lays eggs in May. One scale shell may contain 800 or more eggs. The flat, yellow crawlers that hatch from the eggs in June move away from the mother shell to settle and feed on new growth. This insect has only one generation a year.
Termites, Reticulitermes spp.—Termites may attack yew, especially plants near an infested building. The white, antlike insects build mud runways about the base of a plant or in the crotches of the branches or along the larger branches. They eat.
72 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 51.—Taxus mealybug: infestation on yew. The sooty mold on in- fested needles makes the white, wingless insects conspicuous.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 73
the bark and cambium and may girdle and kill a branch or an entire plant.
Taxus Mealybug, Dysmicoccus cuspidatae (Rau), fig. 51.-— The taxus mealybug is an occasional pest of yew. Its name is descriptive of the white, waxy, slow-moving, sucking insect seen feeding in small colonies on the twigs and branches.
POTENTIAL INSECT ENEMIES
There are several important shade tree pests that have not yet, but may, become destructive in Illinois. Everyone should be on the alert for them. Anyone finding an insect fitting one of the
Fig. 52.—Japanese beetle: adults. Both male and female adults are principally metallic green in color and about a half inch in length. Each has white spots on the tip of the abdomen.
descriptions below should place the insect in alcohol and send it to the Illinois Natural History Survey, Urbana. Early knowledge of the presence of a new pest may result in holding down an in- festation or in wiping it out completely.
Japanese Beetle, Popillia japonica Newm., fig. 52.—The Japanese beetle feeds on the foliage of a wide variety of trees, shrubs, vines, and other plants. It is a ravenous feeder that oc- curs in great hordes.
A native of the Orient, this insect was first found in the United States in 1916, and isolated infestations now occur in Illinois. The adults, metallic green beetles about one-half inch long, have white spots on the tips of their abdomens, just back
74 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 53.—Gypsy moth: A, adult females; B, adult males; C, larvae; D, egg clusters and pupae on the under side of loose bark. The female is buff in color, the male dusky; the larva is covered with brown hair and has blue and red tubercles along the back. The egg clusters are covered with tan hairs. (Photographs from Connecticut Agricultural Experiment Station.)
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES Ue)
of the wing covers. They are strong fliers. They are very fond of eating ripening apples, corn silk, grape foliage, and soybeans. The female deposits eggs in the soil to produce grubs that feed on the roots of grasses. The grubs spend the winter in the soil, resume feeding in the spring, complete growth, and pupate. The adults emerge from the pupae in late June or July and feed for several months. This insect produces one generation each year.
Gypsy Moth, Porthetria dispar (L.), fig. 58.—Of all the leaf- feeding pests that attack shade and woodland trees, the cater- pillar of the gypsy moth is the most destructive. It feeds on nearly all deciduous trees, and, except in the early stages of its development, on many evergreens. Most of the area infested by this insect lies east of the Hudson River. An infestation in Mich- igan was discovered a few years ago, but there is some hope of eradicating it.
The female moth deposits eggs in hair-coated clusters on tree trunks, buildings, and other objects. The full-grown cater- pillar, 2 to 214 inches long, is covered with tufts of long brown hair and has five pairs of blue tubercles along the back followed by six pairs of red tubercles.
The insect overwinters in the egg stage. The eggs hatch as the leaves of trees unfold in spring. The caterpillars feed for about 2 months, during which time they may strip trees of their foliage. Pupation occurs in cocoons fastened to tree trunks. The adults emerge in late July, and the female deposits the eggs that carry the species through the winter. The female is buff in color, the male brown.
Brown-Tail Moth, Nygmia phaeorrhoea (Donov.).—The cat- erpillar of this species feeds on the foliage of a wide variety of trees, including oak, elm, maple, willow, apple, pear, and plum. Like the gypsy moth, the brown-tail moth is confined mainly to the New England states.
The male as well as the female is white, except on the tip of the abdomen, which is covered with brown hairs. The caterpillar is reddish brown and has a broken yellow stripe along each side of its body. The body is covered with stiff barbed hairs, which may cause a very irritating rash on human beings.
The partly grown caterpillar, which overwinters in a nest of webbed leaves, feeds for a while in the spring before pupating. The adults emerge in July, and the female deposits masses of brown eggs on the under sides of leaves.
76 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
ABOUT INSECTICIDES
All insecticides should be handled as poisons. Some are more poisonous to human beings than are others, and some are so haz- ardous that they should be handled only by persons familiar with them. The first step in handling all insecticides safely is to read the label on the package, and the second is to follow the instruc- tions given thereon.
An overdose of a chemical may cause plant damage. In gen- eral, insecticide applications should be made only when a pest species is causing enough damage to destroy the aesthetic value of an ornamental plant. Many insect pest populations are held in check by parasites and predators. The indiscriminate use of pesticides sometimes results in severe plant damage, because the chemicals eliminate parasites and predators of pests, re- sulting in a population resurgence of an insect or mite species which was previously controlled by natural enemies. Generally, certain developmental stages of a pest are more susceptible to chemical control measures than are other stages; therefore, the timing of chemical applications is very important.
Although insecticide applications are depended upon for the control of most insect pests of trees and shrubs, other measures are sometimes used: syringing mite infestations on plants with a strong stream of water; picking and burning the overwintering bags of bagworms to destroy the eggs; covering young trees with cheesecloth to protect them from cicadas; wrapping the trunks of young trees with paper to protect them from borers, fig. 54.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 77
Fig. 54.—Newly set tree, A, wrapped with paper to prevent damage by borers. The paper, about 4 inches wide and specially designed for wrap- ping trees, is spiraled about the trunk of the tree and held in place with a stout cord, as shown in B.
ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
ABOUT SPRAY EQUIPMENT AND ITS USE
A 2- or 3-gallon knapsack sprayer, fig. 55, is the smallest equipment suitable for spraying shrubbery and small trees. The low pressure and low rate of discharge of such equipment demand
Fig. 55.—Compressed air sprayer, a convenient sprayer for small jobs.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 719
careful work for complete plant coverage. The trombone-type sprayer, shown in the frontispiece, develops adequate pressure and is convenient for spraying a few shrubs and small trees. The bucket-pump sprayer, fig. 56, also develops adequate pressure for
Fig. 56.—Bucket-pump sprayer, an inexpensive but suitable sprayer for shrubs and small trees. The spray material is mixed with water in a bucket and kept mixed by agitation with a wooden paddle.
80 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
small trees and is useful for treating a larger number of plants. A hand-operated wheelbarrow-type sprayer or small power sprayer, fig. 57, is recommended for any job involving medium-sized plants or a large number of small plants.
Adequate spraying of large trees requires power equipment. A conventional hydraulic sprayer, fig. 58, that develops 500-600
Fig. 57.—Small power sprayer. This is a satisfactory sprayer for shrubs and small trees.
pounds pressure and has a pump that delivers 30—40 gallons per minute is suitable for spraying large trees. However, if all the spraying is done from the ground, a great deal of spray will be wasted in trying to reach the tops of tall trees. Waste can be reduced if some of the spraying is done from a tower built on the sprayer.
A mist blower, fig. 59, is more suitable than a hydraulic sprayer for use with large trees. In the mist blower, a spray con- centrate is discharged into a blast of air that travels through an outlet at a velocity of 100-120 miles per hour. The outlet can be manipulated to direct the spray concentrate to all parts of even large trees.
ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES §1
Incomplete spray coverage of a tree may serve to check the ravages of a leaf eater, such as the cankerworm, but control of scale insects or control of the bark beetle that transmits Dutch elm disease requires complete coverage. This is difficult to obtain even with the best of equipment. The tree must be sprayed sys- tematically from many angles and at a time when the wind ve- locity is essentially zero. Careful inspection of a tree or shrub after spraying shows whether proper coverage has been obtained.
ell OOM AG
Fig. 58.—Power sprayer in operation. This machine, known as a hy- draulic sprayer, will do an excellent job of spraying trees of small and medium sizes.
82 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Fig. 59.—Mist blower or roto-mist sprayer in operation. This machine is particularly useful for spraying large trees.
INDEX
This index includes technical and common names of insects and com-
mon names of trees and shrubs.
Page numbers of illustrations are indicated
by boldface type. A page number for a subject may indicate the beginning of the section or subsection in which the subject is discussed. Names are listed in the singular regardless of whether they appear in the text as singular or plural. The name of an insect or disease may refer either to the thing itself or to the damage it causes.
A Aceria snetsingeri 36 Agrilus anxius . ial Ailanthus hs webworm : 3,4 American elm (see “also Elm) : Les Bil. 2B, BS) Anisota rubicunda a pee G Aphid . if, Bs AG We boxelder , ei ae. 12 Cooley spruce gall 20, 21, 64 Eastern spruce gall eno: elm cockscomb gall a2Z9 leaf ; 28, 29 Norway- maple 47 painted maple = aly pine bark 56, 57 spirea . 62, 63 tuliptree . 66 willow 68, 69 woollyelm ... 29 woolly hawthorn Ae ily 17 Apple. . 12, 16, 68, 75 oak (gall) . 5 he tree borer, flatheaded > 46; 46, 48 Aphis spiraecola 62
Arborvitae leaf miner
5, 39, 43, 62, 65, 68 F ; 6 Argyresthia thuiella
Sure 6 Ash 6, 24, 40, 60, 62, 69 borer . : 4 7, borer, red- headed 6,7 mountain 7-8 Aspen .. 59 Aspidiotus ancylus 28 perniciosus 18 Atteva aurea . 3 age 3 Austrian pine 54,57, 58
Bagworm. 5,5, 389, 43, 65, 68, 76, 77 Banded elm leafhopper. . . . 33 Bark aphid, pine 56, 57 beetle hickory 36 juniper 38
83
native elm < abel smaller European elm. 31, 32 Beetle
elm leaf . 24, 25 cottonwood leaf . 60 hickory bark . 386 Japanese 73, 73 juniper bark 6 he! May. 48 native elm bark 31
smaller European elm bark 31, 32
Birch 11 borer, bronze 11 skeletonizer 11 white 11
Bittersweet 33
Black cherry 12 locust 40 vine weevil — : 69, 70 walnut curculio 68
Bladder gall, maple 45
Bladder-gall mite, maple 45
Blue spruce, Colorado . . 64
Borer . 1 sks, oh 66, 68, 17 ashwieie 5 "1, 8 bronze birch | 11 cottonwood 59 dogwood 3 20 elm . 2 29, 31 flatheaded apple tree 46, 46, 48 locust 40 lilae 40, 41 oak 48 poplar 59 poplar and willow . i 59 red-headed ash 6,7
Boxelder sels Bian. oles DUCwR aaah autokey he 2 lalieed2 aphid Lay Meche Se Misa Licy
Boxwood 5 él leaf miner ; 5 Me)
Brachyrhinus sulcatus . 69
Bronze birch borer Pons! lil
Brown-tail moth ‘ 5 TS)
Bucculatrix canadensisella ell:
Bud scale, spruce . : 64, 64
Budworm, spruce 5) Gb
Bug boxelderwey eee ee lela June j ee! NESTA | aS sycamore lace 65, 66
84 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Burioakee ee os 8 eee oe 50 Butternut’; 4s Gees es 2! 2. 468
Cc
Cankerworm, spring
ecda2a 2s Carolina poplar rece (D9
Carpenterworm 48, 59 Catalpa 14,15 sphinx Sever as aes te eek MARS Caterpillar yee ee ee eG eastern tent 6 ao oy dl ile: walnut sets 67, 67 yellow-necked 1g, 17, 36 Ceratomia catalpae .. . 14 Chermes QbICtiSy 34 ae aoe. ae ert Od COMIGR o 6 65 6 20, 64 Chermys black 4) 4) ree eS Came Glin gf 6 6 o 6 56 6 a He Chinquapinwe eee ae O Chionaspis
COTM! a iss, ae ey ee eee LUG ULNG od ce eae Os) a eee Chokecherry .. . eee a le Choristoneura fumiferana eee (815) Chrysobothris femorata . . . 46 Chrysomela scripta . .. . . 60
Cicada terse hea ae Be TT,
periodical 48, 49 Citheronia regalis . ..... 387 Clavigerus smithiae. . . . . 68 Cockscomb gall
aphidielia ars. Gace js caves, eho 29
elmies)e Rha tier tee 30 Colopha ulmicola we ahr eit SOO Colorado blue spruce ... . 64 Comstock mealybug ..... 16 Conotrachelus retentus . 68 Cooley spruce gall a 20, 21, 64 Corn silk .. Q 75 Corythucha ciliata Dts eee OD Cottonwood : 59, 60
Borer Paty ie at eens Yt cing een? lose og ob a 6 5 6 5) GO
Cottony maple scale 43, 44 Crab ; : 16, 36 Curculio, black walnut cl cake EME S Cynipidae RM: fe eee ney ey De (Chymwloviey Tron 6 oo 6 « oo | B® D Datana AINLCGENTUMIG ©. tas eee ae Gi ministra . . . Sel) eae WG: Dendrothrips ORDE me eo sant)
Devil, hickory horned ... . 37 DIGI OUS COFLIA 5 a 9 co o 0. 0 eM Dichomeris marginella . .. . 88 Dioryctria zimmermani. . . . 58
Dogwood)... 4) eee
borer... 2". (2 eee scale... sss =O Douglas fir é A 20, 21, 64 Drepanaphis acerifoliae Me oe Yl Dutch elm disease 31, 32 Dysmicoccus cuspidatae . . . 73 E Eastern
spruce gall aphid .... . 64
tent caterpillar . ‘ 12,13 Elaphidion villosum. . 48 limi lai 2 25 265 2ie 28, 32, 48, 75
American 5 ‘ PAL PB) Bie:
aphid, woolly ... . 29
bark beetle
smaller European . 31, 32 mative: << \s. 2 ‘cause atone borer ode 00 eo mee
Chinese . . «4 eee 4
cockscomb gall solve eee ties 0
aphid . . +. on ee disease, Dutch Aerolerae leaf
aphid 28, 29
beetle . ae, leafhopper, banded . eos
scale, European 2. 2b e26 Soemnoranl 6 oo 6 o co ow AW Engelmann spruce .... . 64 Ennomos subsignarius ... . 40 Eotetranychus multidigituli . . 48 Eriosoma QMeTrICanNUN) pO crataegi . . ao) eG Erythroneura bistr ata i. GeO Huonymus) eee scale. <« 4. 3 boa SOO noe European elm bark beetle, smaller . 31, 32 scale. 5 CUR ee 2 eG pine shoot moth & usin ee eG red mite. . . 5... \s, Kum
Fall webworm . . se OS OR 24! Flatheaded appletree panes 46, 46, 48
Fletcher scale nelle Fir, Douglas 20, 21, 64 G Galemuicella lnteola 1. eee
Gall oi. nm % = -) 5 ee
aphid Cooley spruce . 20, 21, a ‘Oa
eastern spruce
ENGLISH:
elm cockscomb ... . . 29 elmmecockscomb . «= .. «= « 30 SOUUVTOAK. « <q s,s. 3 ts maple bladder . « . «.« « 45 mite, maple bladder- . .. . 45 oak apple _.. dei phylloxera, hickory . Spits akc eteae l psyllid, hackberry “unele Be 8S
wool sower . . ) O2n0e Gall- nce
insect . ah BR:
MITE ey < PES Gouty oak gall 52, 53 GOSSYpATiGSPUTAG . «) » «=. 2d Grape . . cme «LD Green- striped mapleworm eG Gypsy moth Shee ve 74, 75
H
Hackberry 35, 35
nipple gall psyllid A ‘ a 5 Ou Bt
witcnes’-broom 35, 36 Hard maple ae Hawthorn NGS Wri HE ae
aphid, woolly 16,17
leaf miner . Nee 19, 20 Hemerocampa leucostigma Slots of 33 FUIGKORVANN - es oo -s , 2 ) BONASNES
bark beetle Soo ABS 36
Palephnylloxera . . ue io
MOMNeUCeVIl =. .aieeea 20s BO Homadaula anisocentra . .. . 48 Honey locust. . . 42, 48, 68 Horned devil, hickory sun areal Hylurgopinus TUSLDES as On Hyphaniria cunea. 2 2S 8
1 Kehnneumonidae 9s s . 2. en a Fehthyura inclusa . .-. . . . 60 Insect enemies, potential . . . 73 Insect gall-producing : 3515353 SCALA en, Sie eS ea 2. J Jack pine .. . 54, 57, 58 Japanese beetle 5 (eh 78: NER DUS ts ic us ws . 48 Juniper . cL meee, 6, 37, 38, 62
bark beetle : ‘ 38
seale 6, 37 , 38
webworm » Oo, 39
K Kermes, oak . 50.50 Kermes pubescens . ..... 50
ILLINOIS TREES: THEIR INSECT ENEMIES 85
L Lace bug, sycamore 65, 66 Lady beetle és Leaf aphid, elm . 28, 29 beetle COGLONWOOd yy. a oleae aoe oOU
elm Be Woh ses Aah es CALIBRE. aro UE Silos Jue
miner Sous. mae O Lol ar borvitae | Ses ees 6 DOXWOOUL ames ls) so =. | coerce l hawthorn oe eee oes OT) ODA I hen oe te teen Ll Leafhopper banded a cling-nervey uae ics ee aeo
redbud . Songs OE a ake LOR OVD, TIBLDOETD 6 a a po 8 al Lepidosaphes ulmi .: ... 8 Leptocoris trivittatus: > 15... V1
Lilae oS eee os 2d 40.41 bOreEN fo kcca sees (40541 cindenw = aeeee A) Be touerenee ae i0) moth, snow- white wack ses 140 THOCUStHWS: ace Ske ete 0 Dla Ckikes sso se eae ta ees O ORCS 3.922. \ePrass eben 40 honey “42, 43, 68 6 + Se ce eC 43 Lombardy poplar a on ea eR Louse (lice); plant, 202. 2). ..8 2
M
Macrosiphum liriodendri . . . 66 Magicicada septendecim . . . 48 Malacosoma americanum ... 12
Maple 6, 14, 43, 47, 48, 75 aphid INOmwayj) eo) uf WORT. painted” = owas a eee a7 lola eel 5 a 4 o 5 s 2 IE bladder- ‘dene mite . 5 GiB aR lagweael 5c i et bear 7 IMGTARERY ce toe net ee, wee cue ae 47 scale, cottony . . 43.44 SOtt a wei oa cee * 43- 4, 44, 45, 45 Mapleworm, green-striped . . 46 Mavyabeetle: 982 1.5 2. 4 « | 48 Mealybug COMStCCKs aa) eb bee ot cee eG cassie. 72, 73 Megacyllene robiniae . Peters wey ety) IMtimrOSalie? PARE eet ees Aaa ct KES WEbDWOLMU Be aos Ske a ons Miner aNdooraaueys Weehe 5 5 6 5 6 6 (& boxwoodileafi 9). =) eae 14 hawthorn leaf 19. 20
ffoakd| leas +9.) cm ~ cca yea
86 Mite : 6 oy ey, 16 European red foe as eS gall-producing Hey insets) locust . > 48} maple bladder- gall . 45 spruce spider ‘ 6, 39, 62 two-spotted spider 33, 62 Monarthropalpus buxi 14 Moth brown-tail 75 cynthia : : 5 European pine shoot 5 5. DI gypsy .. ns 74, 75 Nantucket pine 57, 58 regal . 5 Ot snow- -white linden . 40 white-marked tussock 23, 24 Zimmerman pine 58 Mountain ash 7-8 Mugho pine . . : 54, 57 Myzocallis ulmifolii 2929 N Native elm bark beetle hol Gul Nantucket pine moth 5 57, 58 Needle scale, pine ‘ 54, 55, 65 Neoclytus acuminatus 6 Neodiprion spp 53
Nipple gall psyllid, haekberry 35 Norway maple . ‘ 47 Norway-maple aphid 47 Norway spruce ‘ 64 Nygmia phaeorrhoea . US) oO Osaka 14, 48, 51, 53, 68, 75 apple gall . Rae EO eS oh 4 14 50 gall gouty 52,53 wool sower 52,53 kermes 50, 50 leaf miner aod aul red . 50, 53 white Bd Poets Ve Lei oO Oligonychus ununguis : 62 Oystershell scale . 8,9, 40, 60, 62, 69 P Pachypsylla celtidismamma 35 Pachysandra 5 Be Painted maple aphid ~ AT Paleacrita vernata su ale Panonychus ulmi . me oS Pear .. > TS) Periodical cicada 48, 49 Periphyllus lyropictus 47 negundinis 12
ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Phenacaspis pinifoliae 54 Phloem necrosis ; 33 Phloeosinus dentatus . 38 Phyllophaga spp. 4 48 Phylloxera caryaecaulis 37 Phylloxera, hickory gall 37 Physokermes piceae 64 Pigeon tremex AT Pine . 53, 54, 55, 58 Austrian . 54, 57, 58 bark aphid : 56, 57 jack . 54, 57, 58 moth Nantucket 57, 58 Zimmerman 5 Se Mugho : 54, 57 needle scale . 54, 55, 65 red . 57, 58 sawfly, red- headed . Bee tay, | Scotch . 54,57, 58 shoot moth, European Ut iaeger( white se, 54, 56, 57 Pineus strobi . NOMAD Pissodes strobi 54 Plant louse (lice) . 2 Plectrodera scalator 59 Plum 715 Podosesia syringae fraxini el okt | syringae . 40 Popillia japonica Tes Poplar 48, 59, 68 and willow borer = Be borer 59 Carolina . 59 Lombardy 59 tent maker . 60 Porthetria dispar 75 Potential insect enemies 73 rrionoxystus robiniae 59 Privet 60 thrips . , 60 Profenusa canadensis 20 Pruner, twig . . S 48 Pseudococcus comstocki La . 16 Psyllid, hackberry nipple gall 5 ae Pulvinaria innumerabilis . . . 43 Putnam scale 27, 28 R Redbud aren 61, 61 leafhopper 61, 61 Red-headed ash borer . 6, 7 pine sawfly . 54 Red mite, European . 18 oak yae: 50, 53 pine . 57, 58 Regal moth . 37
ENGLISH: ILLINOIS TREES:
RenICULItErmes SPP: « «= =. « . Wl
Rhyacionia (NDING 5. Sa AT eee 5h WUESEGON(G ss) Se) ey dime yicom ed PO Ss MUIONCUMERIG:, = 6. < som oe 1D Nonmeosescale. . . . . « . 18,18 Saperda PILLCU LULU Vat) AIR oS as Oe DO PIVLCMUOCLO Ty ss Se) ee ee 2D Sawfly .. Ser a eae DS red-headed pine Ry et Gat ay| Scale ae SSO IRR Aa! = Tee. 76 cottony maple 43, 44 GGewWoodeks = 7s «das. 1's 220 euonymus seg 33, 34 Buropeanvelm. =. =. . . 25, 26 Fletcher ae Tol, Al VES SOiy Ay Aes Deere ye juniper . . 6, Cn 38 oystershell — 8. 9, 40, 60, 62, 69 pine needle . : 54, 55, 65 Putnam 27, 28 San Jose. 18,18 seurfy 26, 27 spruce bud 64, 64 tuliptree . . A re) a OD Scaphoideus luteolus ee ek oS Scolytus THISEMIQEUS . «5 sw BT QUuadrwSDINOSUS, = 5 . . . = 36 Scotch pine 54, 57, 58 Seurfy scale . eae 5 AG, il Shadbush . . tetas eMeo Shoot moth, European piness se ea Sitka spruce . . eke Lat G8 iss BOA Skeletonizer, birch - Se Keke ail cet imeh Pole: Smaller European elm bark beetle . Sill, 3 Snow-white linden moth . . ie Soft maple 43-4, 44, 45, NOVOCAMU et out kee td sl a eile = Spanworm,elm . . ~ 5 40 Sphaerotheca phytoptophila 5 6 OE Spaimsescatalpa . s.0ea 2. 2) wdealS Spider mite spruce . sie ote cs 6, 39, 62 two- spotted . 33, 62 Spirea 62, 63 aphid R Sens 62, 63 Spring “galerie | Bo al, Re ee Spruce Ble eis aneOn Good bud scale Salis 64, 64 budworm . Se bathed) Soe ore aa e OD Colorado blue... . aaa 64 Emceimann $s, «sy alga. G4 gall aphid Cooley 5 AY; ee! eastern Si 5 Oe
THEIR INSECT ENEMIES 8&7
INOR WAY: 2! 6 Jct econ alee eed SUCCES wt 5) ular UL hulankc. eae O4
spider mite 6, 39, 62 Sternochetus lapathi é aa: SVCAMOLE. 2 Fee sal rh ea Tue OD
lace bug . 65, 66
T Raxusm(seeralsomview)" 2) 2s) e48 69
mealybug Bh eevee UP4, 033 Tent
caterpillar, eastern 1. 3183
Maken wpODlAT ee meyer AGO Termite .. Bee cs ae weg iL Tetranychus telarius 33, 62
Thamnosphecia scitula . . . . 20 Rhripss privet 7 60 Thyridopterix ephemeraeformis 5 Toumeyella liriodendri
Tree borer, flatheaded aD : ee 46, 48 of heaven oe vO TF CMCUCUIGDG ths pan) tet, A AMRGINE, TOE g 5 6 of alo 5 YY ‘Buliptrecicty no. cy tebe ke tality ee L6G aphidusnrs. Voy ty a uae rat ines) he 66 Scaleuce = 66
Tussock moth, white- marked 23, 24 Twig pruner ‘ wae 48 Two-spotted spider mite : ” 33, 62 U
Unaspis*euonymtr 2.2) 8-3 = 933
Vv
Vasates quadripedes. ... 45
Vine weevil, black 69, 70 WwW Wialnita tot ey ss le, ee GT, caterpillar Be 67, 67 CULCUNOblacksar aealn ane GS Weevil black vine . 69, 70
wyhiitespine iwhe jabs bsg. Ba Webworm
ailanthus 5) JS ee ao ome e. fad cn eee a a ODN Od juniper . 38, 39 mimosa . 42, 43 White- marked tussock moth . 28, 24 White birch’. 70. anh ees yo el OAK ke. Gi Petey a te te ee 0 pine 54, 56, 57 weevil é Willow 60, 68, 75
88 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 47
Willow—continued Y
aphid MES hy, ane WOO RED
borer, poplar and ... . . 59 #£Yellow-necked caterpillar 16,17,36 Witches’-broom 35,36 Yew (taxus) : 69, 70, 71, 72 Wool sower gall seth te RONDO Woolly Z
elmbaphidy 2) mee) eee 29
hawthorn aphi . . . 16,17 Zimmerman pine moth .... 58
SPRAY PREPARATION TABLES
Table 1.—Proportionate quantities of liquid insecticides required to make various quantities of spray.
Gallons of Spray Quantity of Liquid Insecticide Desired 100 1 pint 1 quart 1 gallon 2 gallons 50 VW pint 1 pint 2 quarts 1 gallon D5 V4 pint Vg pint 1 quart 2 quarts 5 2 tablespoons 4 tablespoons 6 ounces 12 ounces 1 1 teaspoon 2 teaspoons 3 tablespoons 5 tablespoons |
Table 2.—Proportionate quantities of powdered insecticides required to make various quantities of spray.
~~ Gallons of Spray Quantity of Powdered Insecticide Desired 100 1 pound 2 pounds 4 pounds 8 pounds 50 V% pound 1 pound 2 pounds 4 pounds 25 14 pound V4 pound 1 pound 2 pounds 5 1 tablespoon* 2 tablespoons* | 4 tablespoons* 8 tablespoons* 1 1 teaspoont 2 teaspoonsf 4 teaspoonst 8 teaspoons t
*Heaping
jLevel
‘ONALD F. LABISKY, Ph.D., Wildlife Specialist VILLIAM L. ANDERSON, M.A., Associate Wildlife Specialist
V. W. CocHRAN, JR., B.S., Associate Wildlife Specialist
'HARLES M. NIXxoNn, M.S., Associate Wildlife Specialist
-ENNETH E. SMITH, Ph.D., Associate Chemist
ICHARD E. WARNER, M.S., Associate Wildlife Specialist
-ONALD L. WESTEMEIER, M.S., Associate Wildlife Specialist
TEPHEN P. HaAveRA, M.S., Assistant Wildlife Specialist
JAVID R. VANCE, M.S., Assistant Wildlife Specialist (ONALD E. Duzan, Junior Professional Scientist
[ELEN C. SCHULTZ, M.A., Junior Professional Scientist
}|LEANORE WILSON, Junior Professional Scientist HARON FRADENBURGH, B.A., Laboratory Technician OBERT D. CROMPTON, Field Assistant
AMES W. SEETS, Technical Assistant
IONSULTANTS AND RESEARCH AFFILIATES:
Section of Administrative Services RoBeErRT O. Watson, B.S., Administrator and Head
Supporting Services
WiuMA G. DILLMAN, Property Control and Trust Accounts
Parry L. Duzan, Technical Assistant
RosBeErT O. Evuis, Assistant for Operations
LARRY D. Gross, Maintenance Supervisor
Lioyp E. HuFrrMan, Stockroom Manager
J. W1tuLIAM Lusk, Mailing and Distribution Services
JERRY MCNEAR, Maintenance Supervisor
MELVIN E. SCHWARTZ, Financial Records
JAMES E, SERGENT, Greenhouse Superintendent
RICHARD WILSON, Technical Assistant
Publications and Public Relations
RoBERT M. ZEWADSKI, M.S., Technical Editor SHIRLEY MCCLELLAN, Assistant Technical Editor LAWRENCE §8. Faruow, Technical Photographer Luoyp LEMERE, TZechnical Illustrator
Technical Library
Doris F. Dopps, M.S.L.S., Technical Librarian Doris L. SUBLETTE, M.S.L.S., Assistant Technical Librarian
SYSTEMATIC ENTOMOLOGY, RODERICK R. IRWIN,
thicago, Illinois; WILDLIFE RESEARCH, WILLARD D, KuIMSTRA, Ph.D., Professor of Zoology and Director f Cooperative Wildlife Research, Southern Illinois University; PARASITOLOGY, NORMAN D. LEVINE, Ph.D., -rofessor of Veterinary Parasitology, Veterinary Research and Zoology and Director of the Center for Iuman Ecology, University of Illinois; ENTOMOLOGY, ROBERT L. METCALF, Ph.D., Professor of Zoology nd of Entomology, University of Illinois; and GILBERT P. WALDBAUER, Ph.D., Professor of Entomology, Tniversity of Illinois; STATISTICS, Horace W. Norton, Ph.D., Professor of Statistical Design and Analysis, Iniversity of Illinois.
Some Publications of the ILLINOIS NATURAL HISTORY SURVEY
BULLETIN
Volume 31, Article 3.—Nutritional Responses of Pheasants to Corn, with Special Refer- ence to High-Lysine Corn. By Ronald F. Labisky and William L. Anderson. July, 1973. 26 p., index.
Volume 31, Article 4—An Urban Epiphytotie of Phloem Necrosis and Dutch Elm Dis- ease, 1944-1972. By J. Cedric Carter and Lucile Rogers Carter. May, 1974. 31 p., index.
Volume 31, Article 5.—Larvae of the Seri- eothripini (Thysanoptera: Thripidae), with Reference to Other Larvae of the Tere- brantia, of Illinois. By Thomas C. Vance. August, 1974. 64 p., index.
Volume 31, Article 6.—Root Infection of Woody Hosts with Verticillium albo-atrum. By Gerald L. Born. August, 1974. 41 p., index.
Volume 31, Article 7—The Mecoptera, or Scorpionflies, of Illinois. By Donald W. Webb, Norman D. Penny, and John C. Marlin. August, 1975. 66 p., index.
Volume 31, Article 8—An Electrofishing Sur- vey of the Illinois River, 1959-1974. By Richard E. Sparks and William C. Starrett. August, 1975. 64 p., index.
Volume 31, Article 9.—Pesticides and En- vironmental Quality in Illinois. By Robert L. Metcalf and James R. Sanborn. August, 1975. 56 p., index.
BIOLOGICAL NOTES
86.—Illinois Birds: Tyrannidae. By Richard R. Graber, Jean W. Graber, and Ethelyn L. Kirk. February, 1974. 56 p.
87.—The Literature of Arthropods Associ- ated with Alfalfa. I. A Bibliography of the Spotted Alfalfa Aphid, Therioaphis maculata (Buckton) (Homoptera: Aphi- dae). By D. W. Davis, M. P. Nichols, and E. J. Armbrust. February, 1974. 14 p.
88.—The Literature of Arthropods Associ- ated with Alfalfa. II. A Bibliography of the Sitona Species (Coleoptera: Curcu-
lhionidae). By W. P. Morrison, B. C. Pass M. P. Nichols, and E. J. Armbrust. Feb! ruary, 1974. 24 p. |
89.—The Life History of the Spottail Darter Etheostoma squamiceps, in Big Creek, Ti! nois, and Ferguson Creek, Kentucky. By Lawrenee M. Page. May, 1974. 20 p.—
90.—A Bibliography of the Northern Corr Rootworm, Diabrotica longicornis (Say) and the Western Corn Rootworm, Dia brotica virgifera LeConte (Coleoptera® Chrysomelidae). By W. H. Luckmann H. C. Chiang, E. E. Ortman, and Marthe P. Nichols. April, 1974. 15 p.
91.—The Distribution of Periodical Cicaday in Illinois. By Lewis J. Stannard, Jr February, 1975. 12 p.
92.—The Literature of Arthropods Associatec with Soybeans. IV. A Bibliography of the Velvetbean Caterpillar Anticarsia gemma talis Hiibner (Lepidoptera: Noctuidae) By B. J. Ford, J. R. Strayer, J. Reid, ané G. L. Godfrey. February, 1975. 15 p.
93.—The Life History “of the Stripetai) Darter, Htheostoma kennicotti, in Big Creek, Illinois. By Lawrence M. Page
February, 1975. 15 p. 94.—Illinois Pheasants: Their Distribution and Abundance, 1958-1973. By Ronald FY
Labisky. February, 1975. 11 p. 95.—The Nest Biology of the Bee Andrenea (Ptilandrena) erigeniae Robertson (Hy) menoptera: Andrenidae). By Lloyd Rt Davis, Jr. and Wallace E. LaBerge. June 1975. 16 p. CIRCULAR
51.—Illinois Trees: Selection, Planting, and Care. By J. Cedric Carter. August, 1966) 123 p.
52.—Fertilizing and Watering Trees. By Dan Neely and E. B. Himelick. December, 1971! (Third printing.) 20 p.
54.—Corn Rootworm Pest Management ini Canning Sweet Corn. By W. H. Luckmann,) J. T. Shaw, D. E. Kuhlman, R. Randell) and C. D. LeSar. March, 1975. 10 p.
List of available publications mailed on request |
|
No charge is made for publications of the ILLiIvois NaTuRAL History Survey. A single:
copy of most publications will be sent free to anyone requesting it until the supply becomes
low. Costly publications, more than one copy of a publication, and publications in short supply:
are subjects for special correspondence. Such correspondence should identify the writer and explain the use to be made of the publication or publications.
Address orders and correspondence to the Chief, Illinois Natural History Survey Natural Resources Building, Urbana, Illinois 61801
ra!
nh, ee 4 4 be : in’ 1 J bi Te RL a my en iy eel fa eae a Sravtlbe gay ke “h r Pigs i" iB ¥ at x" ; \ * Hs nye fw reali rh At roe bint | vie x va big ‘e Ms Gel ee ae Uae { e h ' k a. A : 4 ve af Ng aS al 4 ie voli: a ie, ; * a ; i) y } : ‘gi 4 “a y (hail ve Ww An ad e ie ' Al i Be #, i) i ’ a i i } a he |
ee, A > > ‘ “ ( Axi ® ’ n | i Pe A Pi ; i pt Vy ny. ’ bt ; < ' .f mr } i f.7 A “ 7. x ; Ue } of : / : ‘ 4 he 4 . eA - rant. == 3 4 ‘ > iy x ‘ 4 = Ve : f } i P i a mss i Vf bn +| F nf ep i ¥i , oe GA a4. Ps — > % eS i ) A , c Vv ' = 1 f = ¢ no Jaa t ae d } is a f y ria : : i - = a : 4 Te = bas J u t A ey ') } f A ij } '
MAY 95
UNIVERSITY OF ILLINOIS-URBANA
|
HN
3 0112 018415429
Ve aeame