Glossary of IPM Terms


abaxial – away from the axis; bottom of a leaf

abdomen – in insects, the posterior or hind part of the body

achene – any small, dry fruit with one seed that does not burst when ripe

action threshold – pest density of an increasing infestation used to initiate control measures; may be based on experiencerather than experimentation and require readjustment when density/damage relationships are better understood (see economic threshold)

active ingredients (AI) – the component of a pesticide formulation responsible for the toxic effect

acute toxicity – a measure of imminent danger from a chemical; usually expressed as milligrams of chemical to kilogram oftarget organism (mg/kg) required to kill 50% of a target population following exposure (i.e., lethal dose, or LD50); mayalso include information on how doses are administered (dermal, oral, inhalation) and time required to observe effects

adaxial – towards the axis; top of a leaf

adult – a plant, animal, and insect that is fully grown

adulterate – to corrupt, debase, or make impure by adding poor or improper substances

aerial applicator – a person making chemical application by aircraft or helicopter

agricultural revolution – the process of humans moving from a mobile hunting/gathering culture to a more sedentaryexistence by domesticating and raising plants and animals at a fixed location allowing permanent settlement and urbandevelopment

agriculture – the science of raising plants and/or animals for food, clothing, or other human valued resources

air blast sprayer – machine designed to treat tree crops with pesticides by placing droplets highly diluted with water in avery strong air current that disperses them into the canopy as high as 30m. Tank capacity is usually 400-1000 gallons. Application rate is typically about 100 gallons per acre or 25% of the amount required to completely wet all foliage.

alate – possessing wings

algae – a group of plants, one-celled, colonial, or many-celled, containing chlorophyl and having no true root, stem, or leaf; found in water or damp places

allomone – interspecific interindividual chemical communication benefitting the producer; a chemical that benefits the producer species to the detriment of a different recipient species

allopatric – originating in separate areas; not contiguous in space and/or time

ametabolous – not subject to metamorphosis

amorphous – lacking a defined shape or structure

anecdotal – based upon limited and often casual observation rather than rigorous and controlled investigation

anemophilous – wind-borne, most commonly applied to pollen

annual ring – a more or less concentric circle, a cross-section of a tree stem; usually each consists of large cells oriented towards the center of the stem that were produced in the spring followed by progressively smaller cells toward the bark as a season progresses. Each circle or ring is deposited each year. Pine, oak, pecan and many other trees exhibit this annual growth pattern, but other trees like cottonwood do not. They are useful in detecting tree age, and can reflectrainfall, pollution, flooding, insect infestation, etc. — to a degree these growth patterns are sensitive to such events

annual – possessing a life cycle that produces one generation each year; many plants and some insects are annual

antennae – pair of sensory organs on the head of most adult insects and on immatures of ametabolous and hemimetabolousinsects, lacking in larvae of holometabolous insects

apical – at the top

apocryphal – undocumented material whose veracity is in doubt

appendage – any structure attached to a part of the body of an organism (Glossary of PM)

application equipment – machinery used to apply pesticides

applicator licensing – mandatory procedure proscribed by EPA and generally delegated to the states to ensure personsusing pesticides are properly trained

applicator – person responsible for making pesticide applications

approved common name – the vernacular epithet recognized by an official organization as a designator for a species; generally used in conjunction with the scientific name. The Entomological Society of America, for example, publishes and updates periodically a list of such names. The same species may be assigned more than one, common name, unlikescientific names.

apterous – lacking wings

aquatic – living in water

arista – a large bristle, located on the dorsal edge of the apical antennal segment in some Diptera (Glossary of PM)

arthropod – invertebrate animals (phylum Arthropoda) with jointed legs and a hard external skeleton, e.g. insects, spiders, crustaceans and millipedes

arthropod complex – those arthropod species associated with a human valued resource; includes pests, parasites, predators, pollinators, detrivores, saprovores, etc.

arctic – the polar region in the northern hemisphere

asymmetric – not divisible into equal halves, irregular

author citation – documentation of a source of information specifying who, when, and where, to allow independent examination of the reference material by others; a special case is author of scientific names noted after the specific epithet where only who is given.

avoirdupois – system used to measure weight in English speaking countries, viz, ounces, pounds, pints, quarts, etc.

axil – the angle between leaf petiole and stem, twig and branch, etc.


bacteria – microscopic procaryotic organisms, which commonly have a spherical, rod, or spiral shape but are sometimes more complex (Glossary of PM)

balloon – describes the dispersal method of insects and spiders that spin silk thread and can travel on air currents to distant sites

banding – technique for monitoring arthropods using a corrugated cardboard strip placed around a branch to provide a refuge that is periodically inspected for inhabitants

bark – protective covering of trees and shrubs

base temperature – The temperature below which an organism does not develop.  This parameter is experimentally determined for each organism of interest and used in Degree-Day Models to aid in measuring physiological time.

Batesian mimicry – form of mimicry where the model is distasteful and the mimics are not. Phenomenon was described by Bates.

beak – colloquial expression for protruding mouthpart structures of a sucking insect (see proboscis)

Berlese – the inventor of a collection method using heat to drive small organisms from complex sample material placed over a funnel into a jar of preservatives for later study. Tullgren modified the apparatus by using a light bulb as a heat source

biennial – a two year cycle; some plants and insects require two years to complete a life cycle

bilaterally symmetrical – divisible into two equal halves; a property of many animals including most insects, but few if any plants

binomial system of nomenclature – system of naming species using two names followed by the author, Curculio caryae (Horn), for example. Parenthesis around the author show the genus was revised from the original placement by the author. Carolus Linnaeus is credited with standardizing and popularizing this system of naming used today.

biological control – the use of living organisms, such as predators, parasitoids, and pathogens, to control pest insects, weeds, or diseases. Typically involves some human activity.

biological magnification – the increase of the concentration of a substance as it moves through a food chain; classic example is DDT at low concentration in water is sequestered by algae and concentrated further as organisms are consumed until finally raptors and other top predators and decomposers possess the highest levels.

biology – the study of life

birds – warm-blooded vertebrates whose bodies are more or less completely covered with feathers and the forelimbs modified as wings; some now argue birds are the remaining living remnants of the primarily extinct dinosaurs

black light trap – an ultraviolet light attached to a funnel collection device and deployed at night to catch insects attracted to it

book lung – a saccular breathing organ in many arachnids containing thin folds of membrane arranged like the leaves of a book (Merriam-Webster)

borer – general term describing insects (often Coleoptera and Lepidoptera) that excavate wood for food and shelter; also a tool used for boring

brand name – the commercial name of a pesticide, usually trademarked. Note, different brand names can designate the same active ingredient. Read the label.

breeding – the action or process of bearing or generating organisms; in agriculture it usually designates deliberate manipulation of parents to obtain improved offspring

buds – a small lateral or terminal protuberance on the stem of a plant that may develop into a flower, leaf, or shoot (Merriam-Webster)

bug – insect in the order Hemiptera

bulbous organ – appendage in some scarab beetles to aid the female in preparing oviposition sites in soil

buttoning – damage symptom where fruit growth is stunted to result in hard, small fruit, i.e. one effect of tarnished plant bug on strawberries


callow adult – recently molted adult before melanization of exoskeleton; also, an unfledged bird

calyx – distal end of a fruit resulting from remnants of the flower after pollination and fruit growth

cambium – a thin formative layer between the xylem and phloem of most vascular plants that gives rise to new cells and is responsible for secondary growth (Merriam-Webster)

campodeiform (larva) – a larval form with an elongate flattened body, wee developed thoracic legs, antennae and cerci Entomology 402 (2009) – Glossary – p. 3 (compare to Neuroptera, Trichoptera and Coleoptera)

carnivore – meat eater, often a predator of other animals

cast skin – exoskeleton of a previous molt of an immature insect

caste system – a level of organization for division of work in advanced species of social insects like bees, ants, and termites; usually includes workers, queen, soldiers, tenders, etc.

catalyst – a substance used that speeds up the rate of a reaction, without itself being changed by the reaction

caterpillar – immature stage (larva) of a butterfly, moth, or sawfly

catfacing – fruit deformation, typically caused by bugs, resulting in small invaginated areas of dead tissue surrounded by larger protruding regions of continued growth whose overall appearance sometimes resembles feline physiognomy

catkins – pollen producing flowers on many anemophilous tree species (pecan, oak, etc.)

caudal – situated in or directed toward the hind part of the body (Merriam-Webster)

caution – a pesticide risk category prominently displayed on the label (see danger and warning)

cellulose – a polysaccharide composed of glucose units that constitutes the primary part of the cell walls of plants

centers of origin – the geographical location where an organism (species, genus, etc.) is native; presumably useful in locating natural enemies, resistant host plants and other associated flora and fauna that may prove useful in management

centipede – any of a class (Chilopoda) of long flattened many-segmented predaceous arthropods with each segment bearing one pair of legs of which the foremost pair is modified into poison fangs (Merriam-Webster)

cephalic – directed toward or situated on, in or near the head (Merriam-Webster)

cephalothorax – the fused head and thorax found in forms such as spiders (Glossary of PM)

cerci – slender, paired and segmented sensory appendages arising from the tenth abdominal segment of some insects such as earwigs and cockroaches

certification – a process leading to the state of being certified; required of pesticide applicators, for example

chelicerae – anterior most pair of appendages in the chelicerate arthropods, which include spiders, ticks and mites; generally the most important feeding appendages in these groups (Glossary of PM)

chemical name – the molecular description in words of the active ingredient(s) found in a formulated pesticide.

chemical control – pest management practices that rely upon the application of synthetic or naturally derived pesticides

chewing mouthparts – generally refers to oral organs that articulate to macerate food prior to ingestion; in most insects this refers to the mandibles

chitin – the horny outer coating of an insect formed by cells that secrete a semi-liquid substance which solidifies on exposure to air. It is a high molecular weight polymer of N-acetyl glucosamine linked by 1,4-$-glycosidic bonds. (Glossary of PM)

chronic toxicity – prolonged effects that can occur following exposure to a poison; difficult to characterize, precisely because of variability among subjects and lag time between cause and effect

clam trap – a spring loaded trap that is set open and can be snapped closed by means of a rope or radio control trigger; usually of muslin or canvas; used to obtain complete samples of a given unit or area; considered to provide a more accurate measure than sneaking up on a cabbage with a sweep net, for example

classes – categories in the classification of living organisms ranking below a phylum and above an order, e.g. Hexapoda

classification – a system of naming organisms, soils, weather, or other related materials, events, etc., in an orderly manner

claw – sharp, usually slender, curved nail at the end of a limb

climate – general meteorological condition of the atmosphere over the long term, typically months or years; e.g. warm, cold, wet, dry, windy, cloudy, etc.

clypeus – a plate on the front central part of an insect’s head

coarctate (pupa) – insect enclosed inside a hardened shell formed by the previous larval skin (Glossary of PM)

cocoon – silken case formed by an insect larva for pupation

coevolution – a reciprocal genetic response of two interacting species through time

collophore – small tubelike structure found on ventral side of first abdominal segment in springtails

colony – a distinct localized population within a species; includes ants, termites and bees as well as some tent caterpillars, webworms, etc.

comatose – an unconscious state; may be due to disease, injury, or poison

commodity -a human valued resource

common name – an epithet used to describe an organism in everyday language; often inappropriately used by the lay person, i.e. “bugs” meaning all insects

compound eyes – sight organs made up of many facets found on the head of most insects; they do not occur in immatures of holometabolous insects

concentrate – can refer to commercial pesticide preparation before dilution for use, as in emulsifiable concentrate; also applied to spraying when desired amount of pesticide is delivered to an area using some fraction of the water needed to Entomology 402 (2009) – Glossary – p. 4 completely wet the area, i.e., a 2x spray would use 50% of the water needed to spray to runoff, a 10x spray would use 10%, etc.

coniferous – any of an order (Coniferales) of mostly evergreen trees and shrubs including forms (as pines) with true cones and others (as yews) with an arillate fruit (Merriam-Webster)

control – in experiments; subjects that provide a standard of comparison for new treatments — may include untreated subjects and subjects treated with standard known application

cooperator – in agricultural parlance, usually refers to the grower who works with a scientist

coprophagous – to feed on excrement, i.e. dung beetles, face flies, etc.

copse – mixed forest vegetation often originating from shoots or root suckers

copyright – the exclusive legal right to publish, reproduce, and sell material

cornicles – a pair of protuberances from the dorsal surface of the abdomen in aphids

costa – longitudinal wing vein on an insect, usually forming the anterior margin. Also a prominent striated rod in some flagellate protozoa that courses from one of the kinetosomes along the cell surface beneath the recurrent flagellum and undulating membrane. (Glossary of PM)

coxa – the basal segment of an arthropod’s limb (Glossary of PM)

crawler – generally, the mobile neonate nymph of scale insects prior to settling and becoming sessile

crepuscular – animals that are active in the twilight; i.e., at pre-dawn and at dusk

crochets – a row of hook-like structures found on the walking surface of prolegs of larval lepidopterans that aid in gripping the substrate

crude oil – complex mixture of hydrocarbons existing in a natural state in the earth; current primary source of energy for human activity a small fraction of which is used for spray oils

cucurbits – common name applied to plants in the family Cucurbitaceae

cultivar – a plant construct deliberately developed and maintained in that form by human effort (compare to variety)

cultivated – human preparation and use of land for raising crops

cultural control – pest management practices that rely upon manipulation of the cropping environment (e.g., cultivation of weeds harboring insect pests or natural enemies)

cultural measures – land use practices applied, among other things, to manage pests, plant density, row spacing, irrigation, time of planting, etc.


damage – strictly speaking; biologically, a measurable loss of fitness; economically, a measurable loss in dollars of human valued resource; aesthetically, a measurable loss in emotional value

damaging stages – the life stages of an arthropod that actually are responsible for producing a measurable loss of fitness or human valued resource

danger – a signal word required on labels of the most toxic pesticide (see caution and warning)

deciduous – plants that shed foliage at a particular season or stage; typically is a mechanism to allow dormancy of a perennial plant during unfavorable periods of weather, such as winter in temperate zones

decomposer – heterotrophic organism that utilizes dead organic matter as food, decomposing it into more simple substances (Glossary of PM)

defoliation – removal of foliage, often directly by arthropods with chewing mouthparts or indirectly by the stressed plant responding to aphids, mites, scales, etc. Drought and flood can also cause the effect and deciduous plants defoliate naturally in preparation for dormancy

degenerate – having declined (as in nature, character, structure, or function) from an ancestral or former state (Merriam- Webster)

degree day – A parameter for measuring physiological time. The heat units that occur each day are determined by subtracting the base temperature previously determined for the organism of interest from the average temperature observed on that day at the location of interest. If the average temperature is less than the base temperature, zero heat units are accumulated for that day. Heat units may need to be summed across days to predict an event of interest as specified by a degree day model. (see next entry)

degree day model – A method for predicting when a biological event of interest will occur. The elements are a start day, a base temperature and the sum of degree days (see preceding entry) required to produce the event of interest. Each of these elements is experimentally determined for each organism of interest and combined to form the model.

desert – arid barren land; especially; a tract incapable of supporting any considerable population without an artificial water supply (Merriam-Webster)

desiccation – drying of tissue often resulting in hard or brittle tissue

detrivore – animal that feeds on dead plant or animal material (Glossary of PM)

deutonymph – in the life cycle of some mesostigmatid mites, a non-feeding stage that molts into the adult (Glossary of PM)

diapause – a physiological state of arrested development. Usually triggered by decreasing daily temperatures, decreasing day length, reduced food quality, or some combination of these stimuli; aids survival during unfavorable periods.

dichotomous – bifurcated, splitting into two (nearly equal) parts; a dichotomous key, e.g., divides groups into two parts and divides these again, and so on, until an identification is made.

distal – away from the point of attachment (Glossary of PM)

diurnal – active during the day time

domesticate – human management of animals or plants to adapt them to serve human needs

dormancy – period of inactivity often associated with cold weather and sometimes with very hot weather

dormant oil – a petroleum crude oil distillate, consisting of a complex mixture of hydrocarbons, intended for application to plants not rapidly growing; typically applied to deciduous tree crops during winter months for control of mite, scale and Entomology 402 (2009) – Glossary – p. 5 other sessile pests

dorsal – back or upper side of an organism (see ventral)

dough stage – phenological descriptor of seed maturation indicating endosperm development is coming to completion; period between the gel stage and shuck split in pecan

drift – movement of spray droplets/dust in air currents beyond the intended area of application

dripline – outer edge of the foliar canopy of a plant where liquid runoff from the foliage can still fall to the ground beneath the plant

drupe – a one-seeded indehiscent fruit having a hard bony endocarp, a fleshy mesocarp, and a thin exocarp that is flexible (as in the cherry) or dry and almost leathery (as in the almond) (Merriam-Webster)

duct – tube or vessel that carries the secretion of a gland; a continuous tube formed in plant tissue by cells in a row that lack intervening end walls

dust – a pesticide formulation in dry, finely-divided form (with particle size less than 30 μm) designed for application as a dry dressing without further preparation or dilution (Glossary of PM)

dye – a color, tint, or hue produced by dyeing; cochineal (scale insects) have been an important color source of some dyes, but are being replaced by synthetics


ecological niche – a microhabitat suitable for species to inhabit and live; i.e. lawn thatch, tree holes, leaf galls, hair follicles, etc.

economic damage – the amount of injury that will justify the cost of artificial control measures (Glossary of PM)

economic injury – the degree of crop damage or pest density at which economic losses become significant. The economic injury level (EIL) is reached when an increasing pest density begins to cause economic damage.

economic threshold – the pest density of an increasing infestation at which control measures should be initiated to prevent pest densities from reaching the economic injury level; usually determined by extensive experimentation (see action threshold)

ectoparasite – an organism that lives parasitically on the outside of its host, as with some hymenopteran and dipteran parasitoids. Also, insects that live on the skin of cattle, e.g. ticks, lice, fleas.

edaphic – pertaining to soil

egg sac – a pouch of eggs

egg – the initial life stage of most animals

elateriform (larva) – a larva resembling a wireworm with a slender body, heavily sclerotized, with short thoracic legs and only a few body bristles (Glossary of PM)

electrostatic sprayer – a pesticide spray machine that disperses electrostatically charged droplets into a mild air stream and relies on the positively charged plant to attract the droplets to leaf surfaces

elytra – the hard upper-wings of a beetle (Glossary of PM)

emergency exemptions from registrations – Section 18 and 24(c) of FIFRA provide for states to make pesticides available under tightly controlled conditions where EPA has not (yet) approved their use (see Pesticide section of this CD-ROM)

emulsifiable – a common pesticide formulation able to be suspended in water through agitation; often abbreviated EC, or emulsifiable concentrate

endangered species – species of animal or plant threatened with extinction as determined by the Environmental Protection Agency

endoparasite – parasites that live inside the host and feed internally on its tissues, e.g. tapeworm, liver fluke, lung-worm and many hymenopteran and dipteran parasitoids

endopterygote – condition of internal wing bud development in an insect; also, an insect secondarily wingless but derived from such an ancestor; associated with holometabolous insects (Glossary of PM)

environment – the external conditions (biotic and abiotic) that may act on soils or organisms to influence their development, which includes sunlight, temperature, moisture and other organisms (Glossary of PM)

environmental hazard statement – a part of the pesticide label denoting risks of the product to flora and fauna in and around the treated area

EPA – Environmental Protection Agency

epidemic – widespread and severe, usually huge temporary increase in incidence of an infestation or an infectious disease

epithet – a characterizing word or phrase designating a name of a person or thing

eruciform (larva) – caterpillar; a larva with a cylindrical body, well-developed head, and with both thoracic legs and some

abdominal prolegs (Glossary of PM)

escape – a plant growing away from cultivation, but not well naturalized. Failure of inherently susceptible plants to show infestation and damage even though disease or pest attack is prevalent (Glossary of PM)

establishment number – required information on the pesticide label denoting the facility where the product was made

evolution – a scientific theory that animals and plants originated from other preexisting types, with distinguishable differences being due to modifications in successive generations resulting from natural selection acting on variable characters

evolved – produced by natural evolutionary processes (Webster)

exarate (pupa) – pupa in which the appendages are free and not glued to the insect body (Glossary of PM)

exopterygote – condition of external wing bud development in an insect; also, an insect in which the wing buds develop

externally; associated with hemimetabolous insects (Glossary of PM)

exoskeleton – hard structure developed on the outside of, and giving support to, a body, such as the chitinous covering of an insect (Glossary of PM)

exotic – alien to the area; originating from elsewhere

exuvia – shed exoskeleton of arthropods after molting


facultative – one of two or more possible outcomes dependant upon circumstances, as in facultative diapause, facultative

pollen feeder, etc. (compare to obligatory)

family – a taxonomic subdivision of an order, containing a group of related genera; insect family names end in -idae

feces – bodily waste passed through the anus

fecundity – productiveness, usually characterized by enumerating the number of offspring one average female can produce

federal registration – a responsibility of EPA in approving pesticides for use (see registration)

femur – counting from the body, the third and usually the heaviest segment of an insect’s leg (Glossary of PM)

fertilizer – a substance (as manure or a synthetic chemical mixture) used to make soil more fertile

FIFRA – Federal Insecticide, Fungicide, and Rodenticide Act of 1947 requires that certain useful poisons, such as chemical pesticides, sold to the public contain labels that carry health hazard warnings to protect users. It is administered by EPA and has been amended many times.

filamentous gills – gills which are thread-like; many times longer than wide

fixed oil – produced by a general maceration of plant or animal tissue, e.g. linseed, soybean, cotton, corn, castor, and fish oils; uses are many and include serving as an efficient nontoxic carrier in ULV spraying

flagellum – a whip-like filament projecting from a bacterium or zoospore and functioning as an organ of locomotion. Also called a cilium. (Glossary of PM)

flagging – damage symptom where dead leaves or shoots undergo wilting and/or color changes allowing detection of damage from a distance; also describes ground activities to aid a pilot in conducting aerial spraying

floriculture – cultivation, management and presentation of ornamental and especially flowering plants

flower constancy/fidelity – a behavioral trait in pollinators that results in their visitation of flowers of the same species for some time before switching to alternative flowers; facilitates pollination

flower – a shoot of the sporophyte of a higher plant that is modified for reproduction and consists of a shortened axis bearing modified leaves; especially, one of a seed plant differentiated into a calyx, corolla, stamens, and carpels (Webster)

fluorescent – ability to emit light of a certain wavelength when activated by light of another wavelength; fluorescent dusts are sometimes used to mark insects for later identification

foliar – refers to leaves or the plant canopy

food web – diagrammatic representation of how flora and fauna in an ecosystem are interrelated by denoting which species provide sustenance to which species

forest – a large tract of land covered with trees and underbrush (Webster)

formulation – a pesticide preparation as sold for use containing the active ingredient(s); includes dusts, baits, fumigants, aerosols, granules, emulsifiable concentrates, wettable powders and suspension concentrates

frass – solid insect excrement (sometimes flecking and specking are also used) – see honeydew

fruit – the developing and mature, ripened ovary of a seed plant, e.g. pea pod, nut, tomato

fungi – all non-chlorophyll-bearing thallophytes (i.e., all non-chlorophyll-bearing plants of a lower order than mosses and liverworts) that often show mycelial, spreading growth, e.g., rusts, mildews, molds and yeasts (Glossary of PM)

fungicide – chemical or physical agent that kills or inhibits development of fungus spores or mycelium (or when used in a broad sense bacteria). The term ‘fungicide’ includes all preparations intended for preventing, destroying, repelling or mitigating any fungus. (Glossary of PM)

fungivore – organism that feeds on fungi

furcula – a small fork or forked process (Webster)


gall – a plant growth in response to an irritation by another organism that the latter often uses for food and shelter; causal agents include aphids, wasps, flies, fungi and virus

galleries – excavated spaces in wood, soil, etc., made by organisms such as beetles, ants, termites, etc., to live and reproduce

gallmaker – organisms that induce plant tissue to deform in a manner that provides a microhabitat suitable for food and shelter; typical of some dipterans, hymenopterans, homopterans, mites and fungi

Entomology 402 (2009) – Glossary – p. 7

gastropod – a class of mollusks having one-piece spiral shells, or no shells at all, as certain slugs (Webster)

gel stage – phenological descriptor for seed developmental stage between liquid endosperm and dough

generation time – period from when a life stage begins until the same life stage occurs in the progeny; i.e., period from egg to egg, or adult to adult; this period in insects is sensitive to environmental conditions, especially temperature

genitalia – the parts of an organism that are the immediate instruments of reproduction usually facilitating transfer of sperm to egg; often important in identifying arthropods to species

genus – the principal subdivision of a family next above a species. A group of related species with similar characteristics and appearing to have a common ancestry. (Glossary of PM)

gills – the organ for breathing of most animals that live in the water (Webster)

girdle – to encircle; twig girdlers remove a ring of bark and conductive tissue causing death of the distal portion of the twig

gland – organ that separates certain elements from the blood or haemolymph and secretes them (often with modification) in the form for the body to use; products may be for internal use (hormones), external use (allomones or pheromones) or waste materials

granular – a dry formulation of pesticide and other components in discrete particles generally less than 10 cubic millimeters in size (Glossary of PM)

grass – botanically, a plant of family Gramineae (Glossary of PM)

grassland – land with grass growing on it, kept for pasturage (Webster)

greenhouse – a house, the roof and sides of which consist largely of glass; used to cultivate organisms (especially plants) under controlled conditions of temperature, moisture and sometimes light

gregarious – living in colonies, swarms, flocks or herds; in some gregarious species individuals develop synchronously while in others various aged individuals are recruited

gross weight – the weight of merchandise, or goods, including the packaging; distinguished from net weight (Webster)

grub – typically, the larva of a beetle, or some flies


habitat – a place with a particular kind of environment where plants and animals live (Glossary of PM)

halteres – short-knobbed appendages of true flies; modified hind wings. Vestigial wing on the metathorax of a fly of the order Diptera; necessary for balance during flight. (Glossary of PM)

hamuli – large hooks on the opisthaptor of a monogenetic trematode, referred to as anchors by American authors (Glossary of PM)

harvestable crop – the amount of human valued resource expected to be produced if proper conservation methods are used; when harvestable crop decreases below management costs needed to conserve it, a conscious decision not to apply further management should be considered

harvesting and/or grazing restrictions – information on the pesticide label describing when these activities can occur following the last application of the pesticide

harvesting – to gather in (a crop, etc.) (Webster)

haustellate – a division of insects where the mouth has a haustellum, or proboscis adapted for sucking and lapping food; typical of many flies

head – the anterior region of an insect, which bears the mouthparts, eyes, and antennae

hedging – The mechanical removal of portions of the outer canopy of a pecan tree, usually with the aid of a tractor mounted saw. The purpose is to improve light penetration, air drainage, and to physically control tree size and shape in the orchard to delay the need for tree thinning. The amount of canopy removed and the frequency of removal can vary widely by region and by orchard. This is not a universal practice, even within a region.

hemelytra – the top pair of wings of true bugs, where basal ends are thickened and distal ends are membranous

hemolymph – the circulatory fluid of various invertebrate animals that is functionally comparable to the blood and lymph of vertebrates

hemimetabolous – a type of metamorphous consisting of egg, nymph or naiad, and adult stages of development

herbicide – substance intended to prevent, destroy or control weeds, including algae

herbivore – organism that feeds on plant(s) (see contrast with carnivore)

Hexapoda – six-legged; usually refers to insects

hibernaculum – overwintering form, especially used to describe a silken case constructed by small larva wherein it diapauses

holometabolous – insects that undergo a complete metamorphosis, typically consisting of egg, larval, pupal and adult stages

homeothermic – capable of maintaining a constant body temperature through metabolism and internal regulatory mechanisms

honeydew – the sugary liquid discharge from the anus of certain insects (Homoptera) such as aphids and scales. (BioControl Glossary)

hormone – a chemical agent that controls various physiological processes within an organism, e.g. adrenaline stimulates the heart; auxins and cytokinins in plants stimulate cell proliferation and growth (Glossary of PM)

horticulture – the art or science of cultivating fruits, flowers, and vegetables (Webster)

host – organism that furnishes food, shelter or other benefits to another organism of a different species (Glossary of PM)

human valued resources – things considered important for the maintenance and enjoyment of human existence; i.e., food, fiber, health, fuel and aesthetics, usually denominatable in monetary terms, but not always Entomology 402 (2009) – Glossary – p. 8

humus – the well-decomposed, more or less stable part of the organic matter of the soil (Glossary of PM)

hunting/gathering – a form of human existence where natural resources are used for survival relying on nature to replenish them; some estimates of the carrying capacity of the earth to be 30 million people using this type of culture

hypermetamorphosis – type of development where different larval instars have markedly dissimilar body forms

I, J

idiosoma – posterior of the two basic parts of the body of a mite or tick, bearing the legs and most internal organs (Glossary of PM)

immature – not mature or ripe; any arthropod stage not in the reproductive mature form

inactive ingredients – generally materials in a pesticide formulation remaining as nonreactive byproducts of formulation

increment borer – a specially machined hollow tube with a handle used to drill out a wood core from tree trunks to examine annual growth rings in trees

indigenous – native to the region

induced – the process by which an enzyme is synthesized in response to the presence of an external substance, the inducer. Also, the activation of an occult pathogen, leading to progressive infection and disease; in particular, the provoked transformation of a provirus into a virulent (cytocidal) virus. (Glossary of PM). Some pests like aphids, whiteflies, leafminers, scales and mites are said to be induced when an epidemic occurs following use of broad spectrum insecticides that kill their natural enemies.

inert ingredient – substance in a pesticide product that has no pesticidal action

injury – effect of a causal agent (animal, physical, or chemical),which impairs plant growth, function, and/or appearance; injury may or may not reduce yield or quality

insect – an animal of class Hexapoda (or Insecta) of subphylum Uniramia of phylum Arthropoda. Generally, they have three segments to the body, (head, thorax, and abdomen) with one pair of antennae attached to the first segment (the head), and three pairs of legs and two pairs of wings attached to the middle segment (the thorax). They are mostly terrestrial (though a few species live in freshwater environments and in saltwater marshes). (BioTech Dictionary)

insect collection – captured specimens preserved, organized, labeled and presented according to strict specifications; often used for reference and display purposes

insecticide – chemical preparation that prevents, destroys, repels or mitigates insects

instar – the stage of an insect’s life between successive molts, e.g. the first instar is between hatching from the egg and the first molt (Biol. Control Glossary)

integrated pest management (IPM) – an approach to the management of pests in which the type of plant or animal to be grown is evaluated and a management strategy is devised using physical, cultural, biological, chemical and other available methodologies, as needed, to maintain pests below economic injury densities while profitably and consistently producing the human valued resource with minimum adverse effect on the environment.

invertebrate – a division of the animal kingdom whose chief characteristic is the lack of a spinal column, i. e. insects, slugs, spiders, shrimps, copepods

irrigation – deliberate management of adding water to land for nourishing plants

K, L

kairomone – an interspecific, interindividual chemical, communication that benefits the recipient. An example is a plant scent that attracts the insect.

key (pest) – designates a pest category where management action is expected each season; also a means of identifying organisms by a hierarchical sequence of characters (dichotomous key) or separate lists of characters (synoptic key) used to differentiate them

kingdom – the highest three divisions into which all natural objects have been classified (animal, mineral, and plant kingdoms are of primary concern here)

knapsack sprayer – a case of leather or canvas carried on the back to disperse pesticides

labeling – pesticide information that complements the information on the label, but is not necessarily attached to or part of the container; may include advertising, brochures, newsletters, etc. and be provided by the pesticide producer or EPA

label – the words and symbols attached to the pesticide container or wrapper of the retail package; the label is proscribed by law and use of the pesticide must be in accordance with the label

labium – mouthpart in insects composed of fused second maxillae; homologous to second maxillae of crustaceans (Glossary of PM)

labrum – sclerite forming the anterior closure of the mouth in arthropods, specifically, the free lobe overhanging the mouth (Glossary of PM)

larva – the growing immature stage of holometabolous insects; the neonate six-legged stage of mites and ticks; nematode immatures between the embryo and the adult

leaf necrosis – symptoms of foliar damage indicating tissue death often accompanied with color changes compared to healthy tissue

leafminer – an insect living in and feeding upon cells between the upper and lower epidermis of a leaf; i.e., larvae of Agromyzidae (Diptera), Lyonetiidae and Gracillariidae (Lepidoptera) Hispinae (Coleoptera), Tenthredinidae Entomology 402 (2009) – Glossary – p. 9 (Hymenoptera), etc. Affected tissue, size and shape of the mines are useful in identification of the species causing the injury.

leaves – the lateral organs of a stem; in grasses it consists of sheath and blade (Glossary of PM)

lethal dose (LD) – the amount of a substance that will produce a given mortality (i.e. 50% = LD50) to a population within a given time (usually 24 hours) under specific conditions when administered directly to the organisms; dosages typically administered orally or dermally calibrated by mg of toxicant to kg of recipient; oral LD50 of adult male white rats are often used to calibrate the risk a chemical poses to humans

lichens – a regular association of an alga or cyanobacterium with a fungus, usually leading to the formation of a plant-like structure (Glossary of PM)

life cycle – the complete succession of changes undergone by an organism during its life. A new cycle occurs with the initiation of an identical succession of changes. Note that many insects can differ in their summer and winter forms or in other ways so that the life cycle of an individual may not fully represent the life cycle of the species.

life history – a history of the changes through which an organism passes in its development to its demise; in species with complex life histories, individuals may not fully represent the species

lumpers – a characterization of taxonomists who tend to organize taxa into a minimum number of groupings; generally held in high regard by students


maggot – dipteran larva

magnification – increasing the apparent size of (an object) using a lens or lenses; also refers to increasing concentration of certain chemicals as they pass through a food chain (see biological magnification)

mammal – any of a group of vertebrates whose females have milk-secreting glands for feeding offspring

mandible – a mouthpart of Crustacea and Hexapoda; primarily used for biting or chewing, but highly modified and degenerate types do occur.

manufacturer – a company that creates or builds a product

marine – of the sea or ocean; inhabiting the sea

mechanical control – control of pests by physical means such as the use of screens or row covers (Bio Control Glossary)

mechanization – bringing about the use of machinery in an industry, etc. (Webster)

meconium – the cast skins and residue remaining in the host when a parasitoid completes development and departs

medial – nearer the middle of a body or part

melanize – a tanning process that hardens and darkens affected tissues that occurs in exoskeletons of arthropods following molting

mesothorax – the middle section of the thorax of an insect that bears the foremost wings and center pair of legs

metamorphosis – a change in body form during development of an insect (Bio Control Glossary)

metathorax – the hindmost part of the thorax of insects, bearing the hind wings and the hindmost pair of legs

migrate – movement of an organism a substantial distance from its home range (contrast with dispersal)

millipede – a wormlike arthropod with two pairs of legs per body segment

mimicry – close resemblance of unrelated organisms to one another or to some object in their environment (see Mullerian and Batesian mimicry)

mist blower – sprayer producing a fine spray of small droplets dispersed by a fan. Tank capacity typically 100 gallons or less and rate per acre about 100 gallons or less. (contrast with air blast sprayer and electrostatic sprayer)

mite – minute invertebrates related to insects; poorly known and some argue species numbers may be more than exist in insects

miticide – chemical preparation that prevents, destroys or mitigates mites

model – a simplified representation of a system (which may be expressed in word, diagrammatic or mathematical terms). The use of a model in a scientific context implies (1) that the thing being represented cannot be directly observed, or, in some cases, directly manipulated, and (2) that the model itself is in some degree hypothetical and subject to validation. A model can consist of statements in ordinary language, but models of complex systems often utilize graphic or mathematical symbols. An advantage of mathematical models is that much of the labor of testing them can be performed by computers. (Glossary of PM)

mold – a downy or furry appearance on the surface of organic matter, caused by fungal hyphae, especially in the presence of dampness or decay

molt – to shed or cast off the hair, feathers, skin, horns, etc. at certain intervals, insects molt by shedding their old hard exoskeleton and expanding their newly formed one before it hardens, to allow it to increase in size

monitoring program – a sampling procedure to track progress of potential pests, natural enemies and commodity condition to determine if significant changes are occurring; can form a rationale for undertaking management action

monophagous – eating or using one species of host plant (sometimes concept expands to plant genus)

montane – mountainous (Glossary of PM)

moss – a very small, green, bryophytic plant that grows in velvety clusters on rocks, trees, moist ground, etc. (Webster) Entomology 402 (2009) – Glossary – p. 10

Mullerian mimicry – mimicry that exists between two or more inedible or poisonous species; thought to result from convergent evolution and a mechanism reducing loss to predation by simplification of the recognition process; organisms are often conspicuous in appearance and behavior

mutualism – a symbiotic relationship between two different species in which both benefit from the association; obligatory mutualists cannot survive separately

N, O

naiad – the aquatic immature stage, between egg and pupa, of insects with an incomplete metamorphosis

natural enemy complex – collectively, the parasites, pathogens, predators, and other biotic mortality agents associated with a pestiferous host or host complex

nectar – liquid sugar secreted by many flowers to attract pollinators

nematode – an elongated, cylindrical worm parasitic in animals, insects, plants, or free-living in soil or water (Bio Control Glossary)

nematocide – a chemical that kills nematodes

neonate – a newly hatched or deposited offspring

neotenous – a physiologically mature adult that retains an immature appearance and morphology

neoteny – method of reproduction in which the offspring is produced while an organism is still in, or maintains many characteristics of, its larval or juvenile stage. Phylloxerans (Homoptera) exhibit neoteny, as do salamanders.

net weight – the density, in kilograms or pounds, etc. designating the amount of product independent of the container, as listed on the product label

niche – an ecological term denoting the biotic and abiotic environment required by a species to live and reproduce

nocturnal – active at night

nuptial – suggestive of mating; many insects exhibit complex mating behavior involving odor, vision and sound

nut – the dry, one-seeded fruit of trees, consisting of a kernel, in a hard shell

nymph – the immature stage of insects lacking a pupal stage (whiteflies are an exception)

obligatory – something required, as in obligatory diapause, obligatory mating, obligatory nut feeder, etc. (compare to facultative)

obtect (pupa) – a pupa in which the appendages are more or less glued to the body surface (Glossary of PM)

ocelli – simple eyes on some adult and larval insects (Bio Control Glossary)

oligophagous – animals or parasites that feed on several host species, from a few genera usually in the same family

omnivore – organism that feeds on material of both plant and animal origin

order – taxonomic subdivision that contains groups of related families or superfamilies; usually ending in -ptera in insects (Bio Control Glossary)

ontogeny – the developmental history of an individual (compare to phylogeny)

overwinter – a period of quiescence, hibernation, or diapause by which insects survive the winter; often, only a particular life stage of a species has this capability

ovipositor – an extensible tube on the abdomen of a female insect used to place eggs in plants, the ground or in other organisms

oyster – an edible mollusk belonging to the lamellibranchiate genus Ostrea, family Ostreidae, characterized by an inequivalve calcareous shell; the coverings of some homopteran scale insects are loosely considered to resemble these mollusks


paedogensis – (see neoteny)

palatable – good to the taste, not necessarily healthful. Some poisonous plants that livestock usually avoid are made more palatable by treatment with certain chemicals and consumption may cause injury to the animal.

palp – a part of insect mouthparts, used to test food quality

paralyze – to bring into a condition of helpless inactivity; note most parasitoids and spiders paralyze prey to preserve them as food while their young feed upon them

parasite – an organism that lives in or on another organism (the host) using it for food and shelter generally without killing it during some portion of its life cycle; originally the term parasite was expanded to include insects like hymenopterans and dipterans that ultimately kill their host — this expanded meaning is still in use, but many scientists prefer parasitoid for their insects

parasitoid – an animal that feeds in or on another living animal, consuming all or most of its tissues and eventually killing it; typically designates wasps, flies and other organisms

parthenogenesis – a method of reproduction that does not require mating or fertilization. May be obligatory or facultative and may result in all female offspring, all male offspring or a mixture depending on the species.

patent – a document obtained from the government granting exclusive right to the production, use, sale, and profit of an invention Entomology 402 (2009) – Glossary – p. 11

pathogen – a causal agent of disease. A microorganism capable of producing disease under normal conditions of host resistance and rarely living in close association with the host without producing disease; any microorganism, virus, substance, or factor causing disease (Cantwell, 1974). A microorganism (microbe) that lives and feeds (parasitically) on or in a larger, host organism and thereby injures it (van den Bosch, 1980). (Glossary of PM)

paurometabolous – a term denoting a type of metamorphosis consisting of egg, nymph and adult stages — being a lumper, this term is subsumed under hemimetabolous in this text

pedicel – slender, second abdominal segment that forms a ‘waist’ in most Hymenoptera (Glossary of PM)

pedipalps – second pair of appendages in chelicerate arthropods modified variously in different groups (Glossary of PM)

perennial – living more than one year, i.e. trees, vines and shrubs; continuing existence from year to year by producing colonies, i.e. bee, termite, or ant

pest – an organism that threatens a human valued resource, interferes with human activities, property, or health, or is objectionable (Bio Control Glossary)

pest complex – collectively, the species capable of causing economic damage to a human valued resource; i.e.,the apple pest complex includes arthropods, pathogens, and weeds

pest management – see integrated pest management

pesticide – a substance that kills, debilitates, or repels a pest (Bio Control Glossary)

pesticide dealers – entities or their agents authorized to sell pesticidal chemicals

petiolate – having a long, slender stalk

petroleum oil – liquid solution of a complex mixture of naturally occurring hydrocarbons, yellowish-green to black in color, in the rock strata of certain geological formations; processing yields paraffin, dormant spray oils, summer spray oils, kerosene, benzene, naphtha, fuel oil, gasoline, etc.

phenology – the seasonal life history of an organism; knowledge of phenology of a plant and its associated biota allows anticipation of when many interactions are likely to occur during each season

pheromone – intraspecific interindividual chemical communication; a substance, such as a sex attractant, that is given off by one individual and causes a specific reaction in other individuals of the same species (Bio Control Glossary)

pheromone trapping – use of a semiochemical to lure responsive organisms to a capture device, i.e., sticky trap, funnel, etc.

phloem – living conducting tissue of a plant, a system basically composed of sieve tubes, companion cells, fibers and sclereids to convey the products of photosynthesis, particularly sucrose, from the leaves to growing tissues. A feeding site for many sucking insects that usually excrete a sticky honeydew (see xylem).

phoresy – movement of one organism by an organism of another species; i.e. some scale crawlers move by attaching to a birds leg

phyla – the major divisions of a kingdom

phylogeny – the ordering of species into higher taxa based on evolutionary relationships; attempts to show how living things are interrelated and provide insight into how species have developed through time; the phylogeny of an organism describes its ancestral origins through evolutionary time

phytophagous – plant-eating organisms

plague – a catastrophic epidemic caused by a biotic agent; black death of the Middle Ages, yellow fever, locusts, etc.

plant – belonging to the plant or vegetable kingdom or to set plants or sow seeds (Glossary of PM)

plastron – a specialized gill of minute hairs allowing a thin film of air to cover the body and enhance oxygen exchange with water in aquatic conditions; many insects possess plastrons, even some considered primarily terrestrial

poikilothermic – largely dependant upon external environment for determining body temperature; can be aided by basking, seeking shade, flexing wing muscles to generate internal heat, clustering together in a colony, and other individual and

group behaviors.

pollen – in plants, the male germ cells produced in the anther. When ripe, pollen sacs at the end of the anthers split open to release the pollen. Each ripe pollen grain contains two male nuclei equivalent to male gametes. (Glossary of PM)

pollination – the transfer of pollen from the male anther to the female stigma of a flower. Pollen carried between anther and stigma of the same flower is called self-pollination while pollen carried from the flower of one plant to another of the same species is called cross-pollination. (Glossary of PM)

pollinators – organisms that pollinate

polyhedrosis virus – a group of viruses characterized morphologically by their polyhedral shape

polyphagous – capable of subsisting on many kinds of food; applied to insects that can feed on plants from several plant families

posttreatment interval – the period in time between treatment and a subsequent event; may refer to when reentry is safe, when another treatment is needed, when harvesting or grazing can occur, etc.

potentiation – enhanced toxicity attained by combining two or more toxicants giving more killing power than the sum of the individual toxicities

precautionary statement – information on a pesticide label regarding safe handling of the product, Entomology 402 (2009) – Glossary – p. 12

predaceous – capturing and feeding on other organisms

predator – animal that attacks and feeds on other organisms, normally killing several individuals during its life cycle; usually refers to animals but some use the term to include predation of nuts and seeds

preharvest interval – generally refers to the period from when a final treatment of a product can be applied and the time that must elapse before harvest can begin

prepupa – period between cessation of feeding by the ultimate immature stage and molting to the pupal stage

prey – an animal fed upon by a predator

proboscis – protuberance containing the mouthparts, applied to some insects, worms and mollusks

profit – an amount in excess of the cost of production

prolegs – the fleshy, unsegmented leg-like structures on the abdomens of some larvae, e.g. those of Lepidoptera and sawflies (Glossary of PM)

prorhinal – in front of the nasal chambers

prosoma – anterior tegma of arachnids, consisting of cephalothorax; fused imperceptibly to opisthosoma in Acari (Glossary of PM)

protocol – a set of guidelines or instructions defining how to conduct a procedure

prothorax – the anterior-most segment of the thorax, that bears the first pair of legs (Glossary of PM)

Pterygota – division of insects that includes all hexapods with wings

pubescent – covered with hairs

pupa – nonfeeding stage when the larva transforms to the adult in holometabolous insects

puparium – pupal stage of some families of Diptera

Q, R

quarantine – a designation by a legal authority to isolate infected or infested areas from uninfested areas. All manner of restrictions can be imposed in either or both locations to prevent introduction or spread of a problem. Originally, ships and their goods and occupants were kept isolated in the harbor for 40 days before contact was allowed.

quiescent – not growing

radially symmetrical – form where similar parts radiate from an axis; e.g. starfish, octopus

radius – bone of the forearm in four-legged animals

raptorial – living on prey; predatory: appendages modified to catch and hold prey are raptorial, as in the mantis or eagles

rasping mouthparts – mites scarify the surface of the substrate and feed on exposed tissue using such mouthparts

raster – area at end of abdomen in white grub larvae consisting of anal slit and surrounding spines

reentry interval – time required after treatment before workers can return to the treated area

reentry statement – reentry information required on the pesticide label

refereed journal – a publication that requires authors to address comments and criticisms from peers, often anonymously, before manuscripts are accepted by the editor and published

registration – agricultural and veterinary chemicals registered for sale under appropriate statutes. Details of formulation, safety, efficacy, and environmental acceptability are considered before granting registration. (Glossary of PM)

reproductive – capable of giving rise to viable offspring

reptiles – poikilothermic vertebrates that move on their bellies; i.e., crocodile, alligators, lizards, turtles, and snakes

research/demonstration plots – experimental arenas established, often in cooperation with producers, to test new ideas and/or show how new ideas work under ordinary conditions. Typically, involves performance of plant varieties,

management schemes, chemicals, or other production practices.

researchers – scientists primarily responsible for discovery of new information through careful and thorough investigations typically reported in refereed journals

residual toxicity – the amount of poison remaining in the treated area as time passes after treatment

resurgence – reappearance of an organism to achieve equal or higher densities than before; often occurs in pests following pesticide application

rhizome – a horizontal, underground stem which is distinguished from a root by the presence of nodes, buds and leaves or scales (Glossary of PM)

riverine – area adjacent to a river

root hairs – the thin-walled, hairlike tubular outgrowths from a growing root, which serve to absorb water and minerals from the soil (Webster)

root – the part of a plant, usually below the ground, that holds the plant in position, draws water and nourishment from the soil, and stores food (Webster)


sagittal – designating the longitudinal plane; division separating the body into right and left halves

sampling – examination of representative parts of an area or site of interest in a specified and usually repeatable manner with the intent to gain understanding of the whole Entomology 402 (2009) – Glossary – p. 13

sap – plant exudate usually resulting from a wound

saprophagous – feeding on decaying organic matter (Webster)

saprovore – organism that feeds on decaying organic matter

scales – thin, flat, overlapping, horny plates forming the outer protective covering of many fishes and reptiles, also a common name for some homopterans

scape – the stem growing from the crown of the root, bearing the blossom without leaves, as in the narcissus and hyacinth; a segment of the antenna in some insects

scarabaeiform (larva) – grublike larva with a thickened cylindrical body, well-developed head and thoracic legs without abdominal prolegs, usually C-shaped

scavenger – animal that feeds on dead plants and animals, on decaying matter, or on animal feces (Glossary of PM)

scientific method – a process of investigation that typically applies different treatments to groups of otherwise identical individuals and compares and contrasts the probabilities of outcomes observed to having been due to chance alone; typically results in highly probable interpretations of cause and effects while virtually excluding alternative explanations; validity of the results often dependent upon the thoroughness of the process

scientist – a person specializing in science, using the scientific method

sclerotized – a hardening of the exoskeleton

scorpion – any of an order of arachnids, Scorpionida, found in warm regions with a front pair of nipping claws and a long, slender, jointed tail ending in a curved, poisonous sting (Webster)

secondary (pest) – a secondary pest is one that causes economic damage occasionally

seed – reproductive unit formed from a fertilized ovule, consisting of embryo and seed coat, and in some cases an endosperm (Glossary of PM)

segmented – divided into distinct parts that may be similar as in earthworms and millipede or dissimilar as in adult insects

sessile – animal that is attached to an object or is fixed in place (e.g. various homopterans such as whiteflies and scales; barnacles), also petioleless leaves and pedicelless fruits

seta – a bristle or bristlelike part or organ, the stiff short hairs that cover many arthropods

shellac – resin obtained from scale insects used to make varnish by combining with alcohol

shrub – woody plant with branches from the base and not reaching any great size (Glossary of PM)

sickle-shaped – crescent shaped

signal word – a required word that appears on every pesticide label to denote the relative toxicity of the product. The signal words are Danger-Poison for highly toxic compounds, Warning for moderately toxic, or Caution for slightly toxic. (Glossary of PM)

silk glands – organs on some insects and all spiders used to produce silk

siphon tube – tube used to siphon; formed by modification of conventional mouthparts in sucking insects to access liquid food

skeletonize – to remove soft tissue leaving harder structures in place; often leaf veins are left by skeletonizers feeding on soft tissue

slug – a small mollusk of the family Limacidae, resembling and moving like a land snail, but having only a rudimentary shell or none at all (Webster)

snail – a slow-creeping, gastropod mollusk belonging to the genus Helix, family Helicidae, covered with a protective spiral shell (Webster)

social – living together, usually with an established hierarchy division of labor and reproduction in the most advanced systems

softbodied – possessing a lightly sclerotized exoskeleton, as in aphids

soldiers – e.g., a caste of termites specialized for defense

sowbug – a small terrestrial isopod living in damp places, in gardens and under rocks or logs

special local needs registrations – a category of pesticide regulation allowing specified chemicals, uses, rates, etc., to be applied contrary to the standard label, such variance is obtained by submitting and receiving an approved application

species – a group of individuals similar in morphology, capable of interbreeding and producing fertile offspring. They are morphologically different from other groups and usually do not interbreed with them.

specimen – one individual of a class or group, used as a sample or example of the whole, e.g. the individuals comprising an insect collection are specimens

spider – eight-legged animal; body composed of a cephalothorax bearing the legs and an abdomen bearing two or more pairs of spinnerets used for spinning silk threads to make nests, cocoons, or webs for trapping insects; most spiders possess poison glands for paralyzing prey, but most are not dangerous to humans, exceptions being the black widow and the brown recluse; the spider is an arachnid and not an insect

spinnerets – organs found in certain insect larvae and in spiders, which are used in spinning silken threads (Glossary of PM)

spiracles – small openings in the abdominal segments of insects connected to a system of internal tubes (trachea) through Entomology 402 (2009) – Glossary – p. 14 which the insect ‘breathes’. Openings into the respiratory system in various arthropods. (Glossary of PM)

spittle – liquid excrement produced by nymphs of xylem feeding Homoptera; can also refer to oral excretions of various organisms

splitters – a characterization of taxonomists who tend to organize taxa into the maximum number of attainable groupings resulting in many divisions; generally held in low regard by students

spores – temperature and moisture insensitive resting structures formed by many bacteria and fungi, typically formed for dispersal and subsisting during adverse conditions

spray – dispersion of a liquid in the form of droplets suspended in air

spur – barbed outgrowth; in pear, the twig bearing 5 – 8 leaves and in mixed buds, flowers as well

stalking – the careful approach of one organism to another so the latter is unaware of the former; predators and parasites often employ such behavior with prey

stand – to be upright; agronomic reference to a population of emergent plants

start day – A point in time used to begin calculations for use in a degree day model. This time point may be a particular calendar day or set based on other criteria like budbreak, trap catch or other means.  The latter are often referred to as biofixes.

statement of practical treatment – a category of information required on the pesticide label describing remedies to be applied in case of accidental exposure; typically includes flushing with water, taking an emetic, neutralizing with an acid or base — or avoiding such treatments, depending on the chemical(s) in question. Always read the label.

sting – to prick or wound; a sharp-pointed organ in insects and certain other animals, used to prick, wound, or inject poison to paralyze prey, drive off intruders, or both

stone (fruit) – a category of fruits with a fleshy endocarp containing a hard shell; includes plums, peaches, apricots, etc.

storage and disposal statement – a category of information required on the pesticide label describing how the pesticide should be stored and disposed of after use; often specifies temperature conditions and container disposal procedures. Always read the label.

style – in plants, the portion of the pistil between the stigma and ovary. In maize it is known as the ‘silk’. Also the terminal segment of the antenna of a brachyceran dipteran. It is drawn into a sharp point. (Glossary of PM)

stylet – the slender, hollow, piercing and sucking organs of insects and nematodes that feed on plant sap (Glossary of PM)

subcosta – a subcostal vein or nervure of an insect’s wing

subterranean – beneath the earth’s surface; used to specify primary habitat for some insects or particular life stages as in termites, ants, and weevil grubs

subtropics – designating or of regions bordering on the tropical zone (Webster)

sucking mouthparts – feeding organs on the insect head constructed to consume liquid food, usually in a siphoning action; possessed by plant and animal feeders

suture – the line formed by the meeting of two plates or structures

symbiont – any organism benefitting from a relationship with an organism of another species; typically refers to intestinal flora

symmetric – similarity of form or arrangement on either side of a dividing line or plane; correspondence of opposite parts in size, shape, and position (Webster)

sympatric – originating or occurring in the same area; contiguous in space and time.

synergism – enhanced toxicity of a pesticide attained by combining it with an otherwise nontoxic chemical. Piperonyl butoxide, for example, synergizes certain pesticides by interfering with detoxification pathways, which is harmlessunless the system is also challenged by a pesticide. Term is also sometimes applied to interactive effects of natural enemies on a host.

synoptic – a comprehensive description of something to allow identification without further reference; a synoptic definition of insects provides thorough description of each entity to be differentiated in one place, for example, in entomology, lepidopterous larvae can be distinguished from all other immatures by the presence of crochets on the prolegs – the synoptic description of each of the other orders would be more lengthy; in meteorology, a synoptic map provides a comprehensive and nearly instantaneous picture of the state of the atmosphere. (compare to a dichotomous key)

systematics – the classification of animal and plant species into their higher taxa; sometimes regarded as synonymous with taxonomy (Glossary of PM)

systemic – incorporated into the organisms (or process) to allow physiological expression (a systemic pesticide, e.g., could be absorbed, transported and expressed in various tissues as well as on surfaces treated directly)


target (pest) – the species at which management actions are specifically directed – note, effects of management usually affect many aspects of the site treated in addition to the target pest

tarsus – belonging or relating to the terminal segment of the leg of an insect (Webster)

tegmina – elytrum of certain orthopterous insects (Webster)

temperate – the zone between the subtropic and the polar caps where weather typically can fluctuate with the season from very hot to very cold

tenaculum – a pair of chitinous processes on proturans, which secure the elater (Webster)

terrestrial – confined to, inhabiting, or living on land or the ground (Webster)

thorax – that middle portion of an insect’s body that bears the legs and wings

tibia – the long, slim segment of an insect’s leg to which the tarsus is attached. Podomere of an insect or acarine leg that articulates proximally with the femur in insects and patella in acarines and distally with the tarsus in insects or with the metatarsus or tarsus in acarines. (Glossary of PM)

tick – any of a large group of wingless, bloodsucking insects or mites that infest man, cattle, sheep, and other animals

toxic – poisonous; injurious to animals and plants through contact or systemic action (Glossary of PM)

trachea – the larger respiratory tubes leading from the spiracles to the interior in insects, to allow O2 uptake and CO2 discharge.

trade name – (see trademark)

trademark – a legally protected name or logo used to designate a company or product; primarily intended to distinguish it from similar products made by other companies

transverse – positioned from side to side

trap crop – a managed plant population maintained to differentially attract target pests so that they will cause less damage in the crop grown for profit

trapping – catching animals or insects usually with a device designed for the purpose; e.g. black light, sticky traps baited with chemical attractants, passive malaise traps, etc.

tree – a woody, perennial plant with one main stem or trunk which develops many branches (Webster)

trier – small metal probe for taking samples of paddy or rice or from bulk containers (Glossary of PM)

triungulin – the earliest larval stage of some beetle species

trochanter – podomer of insect or acarine leg that articulates distally with the femur (usually fixed to the femur in insects)

tropism – an obligatory response to a stimulus; phototropism would be a response to light

Tullgren – the inventor who modified the Berlese funnel by using a light bulb as a heat source, hence the Berlese-Tullgren funnel

tundra – treeless area in arctic and alpine regions, varying from bare area to various types of vegetation consisting of grasses, sedges, forbs, dwarf shrubs, lichens and mosses (Glossary of PM)

twig – a small shoot or branch of a tree or other plant (Webster)

U, V

ultralow volume (ULV) – refers to a very low volume application of a tank mix to a treated area; the advent of pyrethroid insecticide, effective at ounce dosages of active ingredient per acre compared to pounds per acre of other pesticide, stimulated development of techniques to deliver small calibrated amounts accurately to wide areas; the use of fixed oils as a carrier in the tank mix often allowed rates to be 2 gallons or less of material per acre

univoltine – one generation each year

unpalatable – not agreeable to the taste

USDA – United States Department of Agriculture, U.S. agency responsible for agricultural research and development in the United States and interaction with other countries. Divisions include the Agricultural Research Service (ARS) with stations throughout the country to conduct research, and the Animal and Plant Health Inspection Service (APHIS), who establish quarantines and regulate and inspect agricultural goods at our borders to prevent foreign pests from being introduced. The USDA also has offices overseas.

variety – a group of individuals within a species that differs in certain characters from other groups of the species, e.g. plants in a species that differ in form, color, fruit size, fruit flavor, etc. (Glossary of PM). Can occur naturally.

vector – literally ‘a carrier’. An animal carrying a microorganism pathogenic for members of another species; the vector may or may not be essential for the completion of the life cycle of the pathogenic microorganism. Also, the vehicle for cloning, typically a DNA molecule (plasmid or bacterophage DNA) capable of self-replication in a host organism.

vegetable – 1. asexual; somatic (Glossary of PM); 2. any plant, as distinguished from animal or inorganic matter (Webster)

venation – the manner in which veins are arranged as of insects’ wings (Webster)

venomous – having a poison gland or glands; able to inflict a poisonous wound by biting or stinging (Webster)

ventral – the underside of an organism; opposite of dorsal

vermiform (larva) – form or shape of a worm (Webster)

vertebrates – animals with a backbone or spinal column (Webster)

virus – an ultra-microscopic (one dimension less than 200 µm) organism. Viruses cannot reproduce alone but must first infect a living cell and usurp its synthetic and reproductive facilities. Responsible for some diseases in plants and animals

viscous – glutinous; thick, syrupy, and sticky (Webster) Entomology 402 (2009) – Glossary – p. 16

volatile oil – compounds extracted from special plant glands; e.g. menthol, camphor, eugenol, wintergreen; in entomology, they have been examined as allomones, kairomones and attractants

volatilization (also called volatization) – invisible process that occurs when a solid or a liquid form of a material is transformed into a gas; evaporation

volunteer – seeds left in the field that come up the following year

voucher specimen – a sample curated for later reference; purpose to ensure correct identification and maintain the capability to verify objects under study even if taxonomic revisions occur

W, X, Y, Z

warning – an advance notice of a pest or disease outbreak or to alert the user to the toxicity of a pesticide product on the container label

water stage – phenological developmental period in seeds between initiation of liquid endosperm and when the endosperm begins to gel

weather – specific meteorological condition of the atmosphere in the short term, e.g. warm, cold, wet, dry, windy, still, cloudy, clear etc. (also see climate)

web – the woven or spun network of a spider, or a similar network spun by the larva of certain insects (Webster)

weed control – the process of limiting weed infestations so that crops can be grown profitably or other operations can be conducted efficiently (Glossary of Pest Management)

wettable powder – finely particulate inert material (e.g. kaolin) containing pesticide that forms a stable (semi-permanent) suspension when added to water (may require tank agitation to maintain suspension) (Glossary of Pest Management)

wild – living or growing in its original, natural state; not domesticated or cultivated (Webster)

wireworm – a slender, hard-bodied larva of any of the click beetles, which often attacks the roots of crops (Webster)

wood – the hard fibrous substance beneath the bark in the stems and branches of trees and shrubs; xylem (Webster)

workers – any of a class of sterile or sexually imperfect female ants, bees, wasps, etc. that do general or specialized work (Webster)

worms – any of many long, slender, soft-bodied creeping animal, some segmented, that live by burrowing underground or as parasites (Webster)

xylem – the woody tissue of a plant; the part of the vascular bundle, consisting of tracheal tissue,  arenchyma, etc. that gives firmness and conducts moisture (Webster); a feeding site for some sucking insects that excrete a relatively nonsticky honeydew

yield – a measure of the production of a human valued resource, typically in kilograms per hectare or equivalent; useful in determining effects of treatments or calculating losses from pests, etc.