Choose five sites per field, at each site, examine five plants. Once a block has been identified for scouting, observe the field and paint an imaginary "V" on that field. This will be the pattern along which you will walk in search of pests. The position of the "V" should vary each time the field is monitored. Before entering the field, choose 5 sites along the "V". At least one of these sites should be along the edge of the field. At each site, closely examine 5 plants. Look at the upper and lower surfaces of each leaf and record the pests present. The perimeter of the field may be important, especially for some pests.
A small asexual fruiting body resembling a cushion or blister.
The chemical in a formulated product that is responsible for the pesticide effects.
An ingredient added to a pesticide formulation or spray mixture to aid or modify the action of the pesticide, or the physical characteristics of the mixture.
Occurs when a cold, dry air mass moves in, accompanied by wind. Here, freezing occurs very rapidly, which makes frost protection very difficult.
A cuplike structure of some rust fungi that contains chains of aeciospores.
A binucleate spore of a rust fungus, formed in a chainlike series in an aecium.
Arrangement of leaves on the stem, placed singly at different heights on the stem or axis. Any arrangement that is not opposite or whorled.
Completes its life cycle within a one year period. Summer annuals complete their life cycle between spring and fall. Winter annuals germinate in fall, overwinter and then flower and complete their life cycle the following spring or summer.
(pl. apothecia) Open, cuplike or saucer like, ascus-bearing fungal fruiting body (ascocarp), often supported on a stalk.
(pl. ascospore) Sexual spore produced by some fungi.
An identifying feature on grasses. An appendage near the lower part of the leaf blade. May be absent or clasping.
The upper angle between a leaf stalk or branch and the stem or trunk from which it is growing.
A pesticide applied as a narrow strip over the crop row. Often combined with inter-row cultivation when herbicides are applied in a band.
A sexually produced fungal spore borne on a basidium.
Insects or mites providing a benefit to crop production, either as natural enemies of pests or as pollinators.
Completes its life cycle within a two-year period. Germinates in the spring, overwinters, flowers the following spring or summer and dies back the following fall.
First sustained moth catch. Used in degree day modelling.
Completing two generations in one summer.
General classification of weeds that have 2 cotyledons; leaves are generally broad and vary in size and shape.
Leaves appear curled, pale green or bronze in colour.
Seedhead of weeds like sand-bur and cocklebur. Various spike-like features on the surface allow the bur to attach to passing people or animals for dispersal.
Cabbage Looper Equivalent (CLE)
Because cabbage loopers can cause more damage/larvae relative to imported cabbageworm and diamondback moth, a larval unit system has been developed to better represent the potential for damage. After totalling the number of cabbage loopers, imported cabbageworm and diamondback moth in a field, multiply the number of cabbage loopers by one, the number of imported cabbageworms by ½ and the number of diamondback moth larvae by 1/5. The sum of the resulting 3 numbers is the total larval units (cabbage looper equivalents). Dividing by the number of plants gives the larval units/plant. Threshold guidelines using the larval unit system are as follows: cabbage: 0.3 larval units per plant; cauliflower and broccoli: 0.2–0.3 larval units per plant.
A soil containing calcium carbonate in the mineral form. These soils have a high pH and are very well buffered against changes in soil pH.
A thin layer of cells that lie between the bark and the wood.
The sepals of a flower; the outermost series of flower parts; it is usually, but not always, green and leaf-like in texture.
A thick-walled asexual spore created through alteration of fungus hypha, which is tubular filament that is the basic structural unit of a fungus.
The pigment which gives plants its green color and is responsible for absorption of light, allowing photosynthesis to occur.
Failure of chlorophyll development caused by disease or a nutritional disturbance; fading of green plant color to light green, yellow, or white.
(Plural cleistothecia) A spherical darkly pigmented fruiting body that produces ascospores.
A case, made partly or completely of silk, which protects the pupa of many insects (especially moths); made by the larva before it pupates.
The pointed, protective sheath that covers the emerging shoot in monocotyledons.
The junction between leaf blade and leaf sheath in grass and sedge leaves.
Specialized stalks on which conidia form.
Chemicals that kill only the parts of the plant on which they are sprayed. Movement within the plant is minimal.
One of the pair of small tubular outgrowths on the hind end of the aphid abdomen
The seed leaves. Often visible when large seeds are opened. These are the first leaves visible in the germinated seedling. Broad-leaved crops or weeds have two cotyledons (dicots). Grasses (monocots) have one.
The temperature at which buds will tolerate for 30 minutes or less without injury.
Family of plants also known as Brassicaceae or the mustard family. Includes cabbage, broccoli, cauliflower, Brussels’ sprouts, kohlrabi, kale, rutabaga, turnip, horseradish and canola.
A continuous layer waxy substances covering over the outer surfaces of the epidermis of plants, it contains cutin and protects against water loss /water gain and other damage.
A period of suspended animation of regular occurrence in the lives of many insects, especially in the young stages.
A treatment directed onto the weeds or soil in such a manner as to avoid contact with the crop.
A resting stage similar to the condition of a plant during the winter.
The spot on the soil surface under the tree indicating the farthest reach of the branches.
The time at which the seedling first appears above the ground.
The outer layer of plant tissue.
A plant in a treated area that has been missed or survived the treatment.
A malformation of plant stems commonly manifested as enlargement and flattening as if several stems were fused.
An abnormal growth of a plant caused by the presence in its tissues of a young insect or some other organism. Aphids, gall wasps, and gall midges are among the major gall-causing insects.
The group of individuals of a given species that have been reproduced at approximately the same time; the group of individuals of the same genealogical rank.
Growth stage in apple that occurs when leaves have emerged and show half an inch of green growth.
A chemical that is toxic to plants.
Herbicide Tolerant Crops (abbreviation - HTCs)
New varieties of crops that have been developed by classical breeding or transgenic techniques to be tolerant to specific herbicides.
A protective case used to survive the winter.
The sweet liquid released from the anus of aphids and some other sap sucking bugs.
Includes 2,4-D, 2,4-DB, mecoprop, MCPA, MCPB, dichlorprop, dicamba, triclopyr, and picloram. At extremely low concentrations, these chemicals can stimulate and/or disrupt the growth of broadleaved plants.
Hours of Accumulated Wetting (hr AWPF)
Total accumulated hours of leaf wetness after petal fall.
Hours of Leaf Wetness
The accumulated hours that the leaves are wet in a tree.
Epidermal leaf structure specialized for secretion or exudation of water; leaf opening at terminus of vein.
Single, tubular filament of a fungal thallus or mycelium; the basic structural unit of a fungus.
The flowering portion of a plant.
Pathogen or its parts, capable of causing infection when transferred to a favourable location
The stage in an insect's life history between any two moults. A newly-hatched insect which has not yet moulted is said to be a first-instar nymph or larva. The adult (imago) is the final instar.
The part of a stem or rhizome between any two nodes.
Between the leaf veins.
The first blossom to open in the cluster.
Name given to a young insect which is markedly different from the adult: caterpillars and fly maggots are good examples.
The time delay between when a plant is infected and when it begins to show symptoms.
The transition into wood or woody tissue, apparent as the development of brown tissue on the outside of a shoot.
An identifying feature on grasses. A flat membrane or band of hairs arising from the inner surface of the leaf sheath, where it joins the leaf blade.
Nutrients required by plants in large quantities for basic plant growth and development.
Paired appendages or jaws, most commonly used in chewing insects to cut and crush food, or for defense. May be modified into a tube-like stylet in piercing-sucking insects such as aphids, leafhoppers and plant bugs.
A vermiform larva; a larva without legs and without well-developed head capsule.
A pest management technique involving the release of synthetically produced sex pheromones in large amounts to confuse males and limit their ability to locate calling females, thereby reducing mating of the target pest.
The actively growing tissue of a plant.
The leaf tissue located between layers of the epidermis involved in photosynthesis.
As important as macro nutrients; they are needed in much smaller quantities by the plant and are often less prevalent in the soil.
Tiny hard bodied survival structures that are resistant to harsh weather conditions.
The process of loosening/shedding the old cuticle ad producing a larger replacement.
A moth is an insect closely related to the butterfly. They both belong to the order Lepidoptera. Moths, and particularly their caterpillars, are a major agricultural pest in many parts of the world.
Leaf tissue around small veins changes colour, but veins remain green.
(pl. mycelia, adj. mycelial) Mass of hyphae constituting the body of a fungus.
Natural Enemies / Biological Control Agents
Predators, parasitoids or pathogens that help to reduce pest numbers, sometimes keeping populations from reaching economic injury levels.
(adj. necrotic) Death of cells or tissue, usually accompanied by black or brown darkening.
A class of insecticides which act on the central nervous system of insects.
Only active at night.
The “joint” of a stem or rhizome; Where the leaf is attached to the stem, and where auxiliary buds and branches are produced.
A chemical used in such a manner that all exposed vegetation is damaged.
System of production where crops are planted without tilling the soil. Used to conserve soil, alter weed populations and reduce fuel use and input costs
Name given to the young stages of those insects which undergo a partial metamorphosis. The nymph is usually quite similar to the adult except that its wings are not fully developed. It normally feeds on the same kind of food as the adult.
A membranous or somewhat leaf-like tube surrounding the stem above each node in the Buckwheat or Smartweed family.
The female reproductive structure of water moulds that contains one or more reproductive cells.
A fungus-like organism, also called water mould.
Persistent, sexual resting spores.
Arrangement of leaves on the stem placed two at a node, on opposing sides of a stem, immediately across from each other.
A type of inflorescence that usually has a central axis and many branches that are themselves more or less rebranched.
An organism that spends all or part of its life in close association with another species, taking food from it but giving nothing in return. Ectoparasites live on the outside of their hosts, while endoparasites live inside the host's body.
A form of reproduction in which an unfertilized egg develops into a new individual, occurring commonly among insects and certain other arthropods.
Peak Flight/Peak Emergence
When adult populations start to decline from last week's counts, the previous week was the peak flight.
A method of measuring caterpillar damage on Brassica to record the percentage of plants infested with caterpillars. Add the number of plants out of the 25 sampled that have 1 or more caterpillars, then multiply by 4. This will give the percentage of plants infested. Threshold guidelines are as follows: cabbage: 20%–30% before head fill; 10%–15% after head fill; cauliflower and broccoli: 20%–30% before heading; 5%–10 % after heading.
Lives for more than 2 years. Compare with annual, winter annual or biennial.
The outer layer of the epidermis produced when canes start to harden off in preparation for winter.
(Plural perithecia)Flask-shaped fruiting body that produces ascospores.
In apples, the growth stage when petals begin to fall from the king bloom.
The stalk of a leaf, attaching the blade to the stem.
A chemical produced by some species of insects to communicate with members of the same species. Frequently, these are ‘sex pheromones’ which a female produces to attract a mate.
The process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a byproduct.
The tissue in plants responsible for the transport of nutrients from the leaves to throughout the plant.
Physiological Plant Disorders
Non-pathological disorders such as poor light, weather damage, water-logging or a lack of nutrients, and affect the functioning of the plant system. Physiological disorder is distinguished from plant diseases caused by pathogens, such as a virus or fungus. Whilst the symptoms of physiological disorders may appear disease-like, they can usually be prevented by altering environmental conditions. However, once a plant shows symptoms of nutrient deficiency it is likely that that season’s yields will be reduced.
A small parasitic organism, smaller than many bacteria, that lives in phloem cells of plants.
Spongy tissue in middle of a shoot or cane.
Growing system where plastic mulch is laid in beds on the soil surface, and crops are planted through small holes punched through the mulch. Useful to reduce weeds, retain moisture and enhance earliness and harvest quality.
An insect that attacks and feeds on other insects, usually smaller and weaker than itself.
Hardened plate in the area right behind the head.
(Plural pseudothecia) Ascospore-producing fruiting body of some fungi.
The 3rd stage in the life history of butterflies, beetles, flies and other insects undergoing complete metamorphosis, during which the larval body is rebuilt into that of the adult insect. Typically a non-feeding and inactive stage.
To become a pupa.
(Plural pycnia) A flask-shaped or conical sporangium of a rust fungus, which develops below the epidermis of the host and bears pycniospores.
(Plural pycnidia)A flask-shaped fruiting body containing conidia and conidiophores.
Class of insecticides which act on the nervous system of insects.
The main stem of a cluster of grape flowers or berries.
Occurs when a cold air mass moves in with minimum wind. Here, the air is usually below freezing and, as heat radiates from the plant, the flower buds freeze. If the dew point is low enough, there may not be any frost visible, just plant tissue damage.
Occurs with an air temperature as high as 4°C or 5°C (39 or 41°F) if there is a low dew point and no wind, because heat is lost from leaves and flowers more quickly than it is lost from the air. This type of frost is less likely to occur on nights when cloud cover traps the heat, or when a light wind ( > 6 km/hr or 4 miles/hr) mixes warmer upper air with colder lower air near the strawberry plants.
Present in front of the anus on the last abdominal segment of some insects; distinct patterns of hairs and spines which can be used for identification.
Reduced-till or Zone-till
Combines the best of both no-till and conventional tillage systems. It uses both shanks and coulters to create a narrow zone of tilled soil that acts as a well-prepared seedbed. The area between the rows is left undisturbed. This dramatically increases the amount of surface residue left on the field, while still creating the fine seed bed desired by many growers.
Resistant Weeds (Herbicide Resistant Weeds)
The inherited ability of some weeds in the population of a particular weed species to survive a herbicide application to which most of the original population was susceptible.
An underground stem, usually horizontal.
The overwintering stage of winter annuals; a circular cluster of leaves, arranged like spokes of the wheel, lying close to the ground.
Damage characterized by brown, roughened markings on the fruit.
Decomposing non-living organic matter.
A shoot or twig of a plant used in grafting, the part of the grafted plant which carries the varietal characteristics that are desired.
A vegetative resting body of a fungus composed of a compact mass of hyphae with or without host tissue, usually with darkened rind.
A vegetative resting body of a fungus composed of a compact mass of hyphae with or without host tissue, usually with a darkened rind.
A family of plants often confused with grasses. Usually the stem is triangular, solid rather than hollow, with indistinct nodes.
The plant structure that produces and disperses seeded.
A chemical used in such a manner that it will kill weeds on a growing crop without damaging the crop.
A pheromone trap used in a mating disruption block to ensure the success of mating disruption. Should catch few to no moths.
One of the separate, usually green parts forming the calyx of a flower.
(Plural setae) The stalk of a moss capsule.
The seedhead of plants in the Mustard family.
A soil active herbicide that is applied at a sufficiently high rate to prevent all plant growth for at least one season.
Saclike fungal structure in which the entire contents are converted into an indefinite number of asexual spores.
Reproductive structure of fungi and some other organisms, containing one or more cells; a bacterial cell modified to survive an adverse environment.
The specialized branch where flower buds are initiated.
A technique to enhance weed control in seeded crops. It is created by tilling the soil early, which encourages the weeds to germinate. After the weed cover is establish, the emerged weeds are killed without disturbing the soil; this is accomplished by using herbicides, non-chemical means like propane flamers, or by mowing very close to the ground. The crop is then seeded or planted with minimal soil disturbance.
Numerous small, white or bronzed puncture marks on the leaf.
A horizontal stem at or slightly below the soil surface that gives rise to new plants at its nodes and tips.
(pl. stomata; adj. stomatal; also stomate) Structure composed of two guard cells and the opening between them in the epidermis of a leaf or stem, functioning in gas exchange.
The process of breaking seed dormancy through changes in temperature. Ginseng seeds require an 18-22 month period of cold to warm to cold temperatures to break dormancy.
New shoot growth pushing from either the roots or the lateral branches, (sometimes called root suckers, or watersprouts).
A chemical added to the herbicide formulation or to the spray solution to improve the dispersing, spreading, sticking or wetting properties of the spray mixture.
(Re: herbicides) A crop that may be damaged or a weed that may be readily controlled by a recommended rate of herbicide.
Two chemicals that are packaged separately and mixed in the sprayer tank.
The primary root; usually larger than the branch roots; and usually present in most annual and biennial plants.
(Plural, telia)A pustulelike sorus formed on the tissue of a plant infected by a rust fungus and producing teliospores.
Terminal Bud Set
Growth stage of tree fruit, when the current season’s growth stops, and a bud is formed on the end of a branch.
Control guidelines that indicate when pesticides should be applied to prevent economic losses. Timing of control measures is critical. Spray guidelines for insect pests are based on an economic threshold where the lost income from not applying a control will be higher than the cost of applying a control. In other words, some damage to the crop is tolerates, as long as this damage does not exceed the cost of the control. Thresholds for disease, weeds, nematodes and vertebrates may be based on weather, site history, stage of crop development and field observations.
A new or additional shoot arising from the base of the original stem; very common in grasses.
A program available in some areas to help field tomato growers determine the optimum time to apply foliar fungicides for the control of early blight, Septoria leaf spot and anthracnose. A network of weather stations monitors conditions affecting disease development. For more information contact Weather Innovations Incorporated at 519-352-5334 or see their website at www.weatherinnovations.com.
A chemical herbicide that moves within the plant.
Nutrient ions move from the plant roots to shoots other plant parts as part of the water flows through the plant.
A planting that attracts insects away from nearby crops helping to reduce economic damage to harvestable crops.
A small rounded projection or protuberance, esp. on a bone or on the surface of an animal or plant.
A thickened, short, underground stem or root, serving as a storage organ containing reserve food ex. common potato.
Completing only one generation in one summer.
Final fruit ripening stage: berries change colour, increase in size, and accumulate sugar.
A legless wormlike larva without a well developed head.
The area under the tree where weeds are controlled by herbicide or mulch.
Three or more leaves or flowers at one node; with the parts encircling the stem and pointing outward like the spokes of a wheel.
Annual weeds that germinate in fall, overwinter, and then flower and complete their life cycle the following spring or summer.
The tissue in plants responsible for the transport of water and minerals from the roots throughout the plant.
Fungal spore with flagella, capable of locomotion in water.