Abdomen: in insects, the posterior of the three main body regions

Acaricide: a chemical which kills and controls mites and ticks

Aestivation: summer dormant, or resting period

Agronomic crop: a field crop, as opposed to orchard, fruit, or vegetable crop

Anal: pertaining to the last abdominal segment

Antennae: the paired, segmented, sensory appendages located on the head of an insect, millipede, centipede, sowbug, etc.

Anterior: at or near the front

Apex: uppermost point, top

Aphid: tiny, soft-bodied, winged or wingless insect that sucks sap from plants and has a pair of cornicles extending from its abdomen; commonly referred to as plant louse

Apical: pertaining to the apex; at or near the top

Armyworm: a name ascribed to the caterpillars of certain moths, particularly those caterpillars which migrate in an army-like group

Arthropod: an animal having a segmented body, an exoskeleton, and jointed legs

Axil: the acute angle formed by a leaf, twig, or branch and the main stem of the plant

Bacterial wilt: a disease of plants often transmitted by sapsucking insects; the causative bacteria clog the plant's water-conducting tissues by producing slime

Bait: a pesticide and food substance mixture used to attract and kill various pests

Basal: at or near the base

Biological control: a pest control strategy which employs methods such as introduction, augmentation, and mass release of parasites, predators, and disease organisms

Bract: one of several leaf-like structures occurring at the base of flowers or seed pods

Broadleaf (or broadleaved) plant: a plant with broad, flat leaves as opposed to the needle-like leaves of evergreens or the narrow, blade-like leaves of grasses

Brood: individuals, usually offspring of the same parents, that hatch at approximately the same time

Bug: in the trusest sense, any insect belonging to the order Heteropte, i.e., stink bugs

Butterfly: an adult insect (order: Lepidoptera) with two pairs of scale-covered wings and clubbed antennae

Calyx: leaf-like structure situated between the bracts and the flower petals (not a part of all fruiting structures)

Caterpillar: the larva of a moth, butterfly, skipper, or sawfly

Caudal: at or near the tail

Cell: closed area of an insect wing bounded by veins

Centimeter: metric unit of length; 0.394 inch

Chalaza (pl. chalazae): on caterpillars, a raised sclerotized portion of the cuticle bearing one to four setae each arising from separate raised areas

Chemical control: the use of pesticides, attractants, repellents, growth regulators, etc. to control or prevent the buildup of economically damaging insects

Chlorinated hydrocarbons: a group of synthetic, organic insecticidal chemicals known for their persistence in the environment and for their action as nerve poisons

Chlorosis: the yellowing of normally green plant tissues, a common symptom of insect damage, disease or nutrient deficiency

Chrysalis: the sharply angled pupa of a butterfly

Class: in the animal kingdom, a division lower than a phylum and higher than an order, e.g., the Class Hexapoda or Insecta

Click beetle: an adult of the insect family Elateridae; a beetle capable of jumping into the air by "clicking" two body segments together

Cocoon: a silken or fibrous case spun by a larva to afford protection during its pupal period

Commodity: any commercial item, including agricultural produce or staples

Complete metamorphosis: the development of an insect through four morophologically different life stages: egg, larva, pupa, adult

Contiguous: adjacent; adjoining; next to each other

Conventional cropping: system of crop production involving regular tillage for weed control, soil preparation, planting, destruction of crop residue, etc.

Convex: raised or curved like the surface of a sphere

Cornicles: a pair of "honey tubes" which extend from the abdomen of an aphid

Cotyledons: a seedling's first pair of leaves

Cosmopolitan: common throughout most of the world

Crochets: curved spines located on the tips of the prolegs of lepidopterous larvae

Crop residue: stalks, dried leaves, seed pods, etc. left in the field after harvest

Crop rotation: a succession of crops planted on the same land over a period of years; a cultural method of disease and insect control

Crown: basal area of stem where roots emerge

Crucifer: any plant of the mustard family, including cabbage, turnip, collard, mustard, and radish

Cucurbit: any plant of the gourd family, including pumpkin, squash, and cucumber

Cultural control: a pest control strategy employing methods such as crop rotation, destruction of crop residue, proper planting dates, weed control, crop fertilization, etc.

Cuneus: a nearly triangular area of the hemelytra (thickened area of forewing) separated from the rest of the wing by a suture; found only in the family Miridae of the order Heteroptera

Cutworm: a caterpillar of the moth family Noctuidae; particularly one which severs seedlings near the soil line at night

Defoliation: loss of foliage

Diapause: a period of dormancy induced by factors other than an unfavorable environment

Disc (or disk): to shallowly break up the soil, usually performed shortly before planting

Dorsal: top or uppermost; pertaining to the back or upper side

Economic injury: sufficient damage to cause monetary loss

Economic threshold: the pest density at which controls should be employed to prevent the population from causing economic injury

Elytra: thickened, leathery forewings which cover the hind wings, common to beetles and earwigs

Epidermis: outer layer of cells in plants and animals

Eradicate: to completely eliminate a particular pest from a designated area

Estivation: see Aestivation

Family: in animal and plant classification, a subdivision of an order containing many related genera

Femur: in insects, the third leg segment from the body

Fibrous roots: slender, thread-like roots, particularly common in grasses

Filiform: long and slender

Forewings: the front pair of insect wings

Frass: insect droppings, usually a combination of leaf fragments or wood borings and excrement

Frostline: the depth to which frost can penetrate the soil

Fungi: lower plants which contain no chlorophyll and are responsible for most plant diseases; molds, mildews, and rusts

Gall: a tumor-like swelling of plant tissues induced by the development of another plant or an animal (including an insect)

Generation: a group of offspring of the same species which develop in approximately the same time frame

Genitalia: reproductive organs

Genus (pl. genera): a group of closely related species

Germination: the process by which a plant emerges from a seed

Germ tissue: reproductive tissue in both parents of plants and animals but particularly the embryo within a seed

Girdle: to sever the water conducting tissues of a plant around the entire stem thereby causing the plant to wilt and die

Gradual metamorphosis: see "Simple metamorphosis"

Granulate: rough; composed of granules; to appear rough, e.g., granulate cutworm

Gregarious: living, feeding, and/or moving in a group

Growing point: bud; meristem; area from which new growth originates

Grub: typically a sluggish C-shaped beetle larva of the family Scarabaeidae having 3 pairs of forelegs and a fat whitish body; also, used loosely to refer to many soil-inhabiting larvae of Coleoptera and Hymenoptera

Halter (also haltere): in Diptera, a slender knobbed structure which takes the place of each hind wing

Head: the first of the three major body regions in insects

Hectare: a metric unit of area; 2.471 acres

Hibernation: winter period of rest or dormancy

Hind wings: the second, and usually smaller, pair of wings often hidden by the forewings when the insect is at rest

Honeydew: a sugary liquid excreted by certain insects of the order Homoptera, including aphids and whiteflies

Hopperburn: a disease of alfalfa, peanuts, potatoes, and other plants caused by the injection of a toxic substance by the potato leafhopper; symptoms include yellowing and spotting of leaves and a reddening of leaf veins

Hornworm: a caterpillar with a horn-like projection on the dorsal side of its 8th abdominal segment; a larva of a sphinx moth

Host: a plant or animal suitable for the nutrition of another plant or animal

Hot spot: a localized area of stressed plants within a field; area indicative of a root problem, chemical injury, or severe injury by aboveground pests

Humus: organic material in the soil; decayed plant or animal material

Immobile: fixed; incapable of movement

Incubation: the developmental period between egg deposition and hatch; also, the time between infection by a pathogen and appearance of disease symptoms

Infestation: the presence of large numbers of an animal or plant pest species where they are likely to cause damage or annoyance to man

Insect: a six-legged arthropod that, as an adult, has three distinct body regions and often one or two pairs of wings

Instar: the life stage of an arthropod between successive molts

Integrated control: a pest control strategy in which all possible techniques are considered and consolidated, thereby preventing economic damage and minimizing adverse environmental repercussions

Kilometer: a metric unit of length (distance); 0.621 mile

Labial palps: jointed sensory appendages arising from the mouthparts of an insect

Larva (pl. larvae): in reference to insects with complete metamorphosis, the immature form occurring between the egg and pupal stages; in reference to mites and ticks, the six-legged first instar

Latitude: the distance in angular degrees north and south of the equator

Leafminer: a small moth or fly larva that tunnels within leaf tissues

Legume: any plant of the family Fabaceae, including beans, peas, cowpeas, soybeans, alfalfa, and clover, which is capable in association with bacteria, of fixing nitrogen

Life cycle: the development of an insect or mite from its egg to its reproductive stage

Light trap: trap designed to attract night-flying insects by means of a light

Litter: forest or crop debris, consisting of decaying or dried plant material often mixed with soil

Lodging: the tendency of a plant to fall over, usually due to root or lower stalk damage

Looper: a moth larva that moves with a distinct humping motion due to the presence of three or fewer pairs of prolegs

Maggot: the larva of a fly

Mallow family: plants of the family Malvaceae, including hollyhock, cotton, marsh mallow, and okra

Mechanical control: a pest control strategy which employs the use of various types of mechanical devices or barriers, such as window screens, ditches, earthen walls, fly swatters, fly papper, traps, etc.

Metamorphosis: a change in form during development: see also: Simple metamorphosis, and Complete metamorphosis

Meter: a metric unit of length; 1.094 yards

Methyl parathion: an organophosphate insecticide and acaricide extremely toxic to most forms of animal life although relatively nontixic to plants; a nerve poison with relatively little residual action

Migration: movement over a relatively great distance

Millimeter: a metric unit of length; 0.0394 inch

Milky disease or milky spore disease: a bacterial disease of the Japanese beetle; sometimes used in reference to a commercial spore preparation used to control the Japanese beetle

Mite: a minute arthropod, usually 8-legged as an adult and closely related to ticks

Miticide: a chemical compound with mite-killing properties

Molt: the process of shedding the outer layer of skin

Morphological characters: those pertaining to size and shape, form and structure

Mosaic: a virus disease symptom consisting of wrinkled and yellow-green mottled foliage

Moth: an adult insect (Order: Lepidoptera) with two pairs of scale-covered wings and variously shaped (but never clubbed) antennae

Motile: capable of movement

Natural control: control of pests by such natural forces as weather and unmanipulated parasites, predators, and diseases

Nectar: a sugary liquid secreted by flowers from a gland known as the nectary

Nematode: an unsegmented, elongate worm (plant pathogenic species usually minute in size)

No-till: a system of crop production in which the soil is disturbed as little as possible

Nocturnal: active at night

Node: that part of a stem from which a leaf grows

Nymph: in reference to insects with simple metamorphosis, the immature form between egg and adult; in reference to mites and ticks, the 8-legged immature form

Order: in animal and plant classification, a subdivision of a class or subclass containing a group of rrelated families

Organophosphates: a class of synthetic, organic pesticides which contain phosphorus, generally have a short residual life, and act as nerve poisons on most animals

Overwinter: to survive the winter, often but not always, in a state of dormancy

Oviposit: to lay eggs

Ovipositor: an elongated structure extending from the abdomen of some female insects through which eggs are deposited

Ovoviviparous: producing eggs which hatch inside the body of the female

Parasite: any plant or animal which lives in or on another organism to the detriment of the host

Parasitoid: a parasite that eventually kills its host

Parthenogenetic: capable of reproduction without mating or male fertilization

Partial metamorphosis: see "Simple metamorphosis"

Pathogen: any disease-causing organism, e.g., certain bacteria, fungi, viruses, protozoans, etc.

Petiole: the stem of a leaf

Phyluum: a major subdivision of classification in the animal kingdom

Physical control: a pest control strategy that employs methods such as heat, cold, electricity, and sound waves

Piercing-sucking mouthparts: a type of insect mouthparts composed of a slender stylet for piercing tissue and a strong pumping mechanism for withdrawing fluids

Pith: soft, spongy tissue located in the center of the stems of some plants

Pollen: tiny male germ cells, or fertilizing elements, of flowering plants

Pollination: the fertilization of the female flower (or the female part of the flower) by pollen

Predaceous: hunting and killing other animals for food

Predator: an animal which kills other animals for food

Preovipositional period: the time interval between emergence of the adult female and the initiation of her egg-laying period

Prepupa: the fat, sluggish, nonfeeding last larval instar just prior to pupating; or, in reference to thrips and male scale insects, the next to the last nymphal instar that has wing pads and short, thickened legs

Progeny: offspring

Proleg: a fleshy abdominal leg of some insect larvae, particularly caterpillars

Pronotum: the upper or dorsal surface of the anterior part of the thorax

Propupa: see Prepupa

Prothorax: the first segment of the thorax and that bearing the first pair of legs, if legs are present

Protozoan: a one-celled animal

Pubescent: hairy, fuzzy

Pupa (pl. pupae): in insects with complete metamorphosis, the life stage between larva and adult

Puparium: in some Diptera, the hardened skin of the last larval instar which becomes a protective covering for the pupa

Pupate: to become quiescent and develop from a larva into an adult

Quarantine: a ban on the movement of certain materials or living organisms from one area to another in an effort to prevent the spread of harmful organisms

Quiescent: in a state of rest or inactivity

Reinfestation: the return of a pest population, usually after the cessation of control measures

Resistance: a) of plants to insects, the ability of a plant variety to repel, appear unattractive to, or tolerate insects, thereby exceeding the yield of other varieties at similar levels of insect infestation; b) of pests to pesticides, the ability of species, races or biotypes, to withstand normally lethal doses of pesticides due to genetic or behavioral selection

Reticulated: net-like; arranged in a net-like manner

Rootlets: small roots

Sanitation: the act of keeping clean; cultural method of disease and insect control involving the removal and destruction of infested or diseased plant material

Sap: any plant fluid, usually used in reference to the liquids in the conducting tissues of trees

Scavenger: any organism which feeds on dead plants and/or animals and decaying organic matter

Scout: to periodically check crops for the purpose of determining the necessity of chemical pest control; a person who performs such a task

Scutellum: in Heteroptera (true bugs), a more or less triangular sclerite located on the thorax behind the pronotum

Secretion: the release of a substance from an organism as a waste product or for the performance of a specialized function

Seta (pl. setae): a hair-like structure

Shatterworm injury: a term referring to corn damaged by early season caterpillars, usually corn earworms, and characterized by the ragged appearance of young leaves as they unfurl

Silk: the style of a female flower of the corn plant

Simple metamorphosis: the development of an insect through three morphologically different life states (egg, nymph, adult) with no prolonged resting stage; gradual or partial metamorphosis

Skeletonize: to feed upon leaf tissue to the extent that only the midrib and veins remain

Solanaceous: pertaining to plants of the family Solanaceae which includes tomato, tobacco, potato, pepper, and many weeds

Sooty mold: a dark fungal growth which develops on foliage covered with honeydew secretions from insects

Species: a genetic subdivision whose numbers are capable of mating and producing fertile progeny

Spiracle: in insects, a pore through which diffusion of gases, or respiration, takes place

Stamens: the pollen-bearing filaments of flowers

Staminate: of or pertaining to a male flower, i.e., having no pistils, only pollen-bearing filaments

Stem mother: a wingless, parthenogenetic adult female aphid

Subterranean: below ground

Subtropic: of or pertaining to near tropical conditions

Succulent: in reference to plants, young, tender, and turgid

Systemic insecticide: a chemical absorbed by a plant or consumed by an animal which subsequently kills insects feeding on or within the treated organism

Taproot: a large, central fleshy root

Tarsal formula: the number of tarsal segments on the front, middle, and hind tarsi, respectively

Tarsus (pl. tarsi): the last (fifth) major insect leg segment, itself divided into several small segments

Tassel: the male flowers of a corn plant; to produce tassels

Taxonomic: of or pertaining to the systematic classification of living organisms

Temperate zone: either of two regions of the earth (one in each hemisphere) which lie between the polar circles and the tropics

Terminal: of or pertaining to the end; occurring at the top

Thoracic: of or pertaining to the thorax

Throrax: the second major body region of adult insects from which the legs and wings arise

Thrips: a minute insect that has two pairs of fringed wings and rasps plant tissues

Tibia (pl. tibiae): fourth segment of an insect leg, located between the femur and the tarsus

Toxin: a poisonous substance

Translocate: to move a substance within a plant from one site to another

Transverse: across; from side to side

Tropic zone: that region of the earth along the equator extending north and south to the temperate zone

Tuber: an enlarged portion of an underground stem

Tubercle: small knob-like protuberance

Unpalatable: displeasing to the taste

Variety: a strain within a plant species having its own characteristics

Vector: an agent of transmission; carrier; an insect bearing disease organisms

Ventral: of or pertaining to the underside

Vestigial: rudimentary; degenerate, atrophied; of or pertaining to the last trace of something that once existed

Virus: a submicroscopic, disease-cuasing agent

Viviparous: bearing live young as opposed to laying eggs

Volunteer: a plant which emerges from seed or other remnants of a previous year's crop

Voracious: insatiably hungry

Weevil: a snout beetle often found feeding among flowers, seed, or stored grain, including billbugs and curculios

Whitefly: a minute white insect, moth-like in appearance, that has two pairs of wings and is related to aphids and leafhoppers

Whorl: a circular arrangement of leaves around the stem, as in corn or sorghum

Wilt: to become flaccid and droop; sometimes a symptom of insect damage or disease, usually evidence of poor water translocation

Wing covers: see Elytra

Wing pads: small rudimentary wings seen on late instar nymphs before they molt into winged adults

Wingspan: width of insect across the wings when they are fully spread

Wireworm: the slender, soil-inhabiting, root-feeding larva of a click beetle

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