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Alert: Making Pesticide Applications in School/Community Gardens



pH below 7.

Action or damage threshold

The level of a pest population at which control is initiated.

Acute toxicity

Injury that occurs soon after exposure to a pesticide.


Contains plenty of air.


pH above 7.


A form of nitrogen that is commonly found in the soil.


Without oxygen.


Plants that reproduce by seed and live for a single year.


Organisms that release toxins or otherwise change conditions so that activity or growth of the pest organism is reduced.


Small soft-bodied insects with long, slender mouth parts with which they pierce stems and leaves to suck out plant fluids.


A type of bacteria found in compost piles that can fix atmospheric nitrogen into a form plants can use.


Single celled organisms that require a host plant or some other organic material as a food source.

Bed planting

Growing vegetables in closely spaced rows that grow together at crop maturity.

Beneficial insects

Insects that are beneficial for crop production because they pollinate plants, attack insect pests or serve other useful purposes.


A plant that lives for two years. It produces leaves in the first and flowers in the second.

Biodegradable plastic mulch

Plastic mulch that degrades in the environment.

Biological control

Any activity of one species that reduces the adverse effects of another.

Black plastic mulch

A plastic mulch that is black in color.


The formation of a seed stalk instead of an edible portion of the plant.

Blossom-end rot

A calcium deficiency in tomato and pepper fruit that causes the tip of the fruit to blacken and rot.

Bone meal

Ground up animal bones that are an excellent source of phosphate, calcium and trace elements.


Dicot weeds that have meristems at the terminal end of their branches.

Burpless cucumber

Mild-flavored and the skin is free of bitterness.

Butter and sugar corn

White and yellow colored kernels are mixed on the ear.


Caterpillars that attack cole crops.


A muskmelon of the round-to-oval, firm fleshed, no sutured, heavy-netted type.

Carbon to nitrogen ratio

The ratio of the amount of carbon in organic matter to the amount of nitrogen that it contains.


A somewhat rounded melon with a smooth rind and white flesh.

Cation exchange

The ability of clay and humus to attract and exchange positive ions.

Chronic toxicity

Injury that occurs after long-term exposure to a pesticide.


A constituent of soils that consists of particles less than 0.002 mm in size.

Clear plastic mulches

Plastic mulch that is clear and allows light to penetrate.

Cold frame

An unheated structure used to start transplants.

Companion planting

Plants that protect neighbors by repelling pests.


Decayed organic matter that contains nutrients and organisms, which enrich the soil.

Cool season vegetables

Plants that grow best when temperatures are cool.

Cover crop

A vigorous fast-growing plant that covers the soil surface and improves the soil.

Crookneck squash

Fruit are elongated with slim, long, slightly to very curved neck.

Crop rotation

Planting different crops in the same place two years in the row.


Plants within varieties that breeders have developed and are distinct from each other.

Cultural weed control

Cropping practices that optimize vegetable growth.


A disease that attacks seedlings, causing rotting near the soil line.


The conversion of nitrates into atmospheric nitrogen by soil microbes in water logged soils.

Dermal exposure

Pesticide is absorbed through the skin.

Dolomitic limestone

Lime that supplies both calcium and magnesium.

Double digging

A process whereby the gardener works the topsoil and also loosens the subsoil.


Movement of water away from the surface of a garden either down into the soil or by flow across the surface.

Dried blood

Blood of animals that is collected from slaughterhouses. It contains high levels of nitrogen.

E. coli

A bacteria associated with animal wastes that can cause serious health problems.


The female flower of corn that produces seed after pollination.


The structure within a seed that develops into a plant.


On hillsides, it is the direction your garden faces.

F1 Hybrids

Cultivars resulting from a cross between two different true breeding (referred to as inbred) parents.

Field capacity

The maximum amount of water your particular soil will hold.

Fish meal

Ground up fish. Contains nitrogen and phosphorus.


An easily worked soil.

Frost pocket

A low-lying area where frost occurs late in the season.

Frost-free date

The average last day of frost for a specific area.


Multi-celled organisms that reproduce by spores and rely on living or dead organic matter for food.


A fruit with a hard outer rind that is used for decoration.


A category of weed that are monocots, have narrow leaves and a growing point at our just below the soil surface.

Green manure

A cover crop used to add nutrients to the soil and choke out undesirable plants.


A ground rock material that contains potassium and trace elements.

Gynoecious cucumbers

Hybrids whose plants have all female flowers.


The process whereby transplants top growth and develop greater tolerance to stress.


The combination of a pesticide's toxicity and your exposure to the pesticide

Heavy soil

A soil that contains a high proportion of clay and is poorly drained.

Heirloom cultivars

Cultivars that are more than 100 years old and whose seeds are passed down from generation to generation.

Hill plantings

Planting multiple seeds together in clumps.


A round melon with smooth rind and green flesh.

Hot caps

Individual structures placed over a vegetable plant that warm the temperature and protect the plant against frost.


A heated cold frame.


A substance that results from the decay of organic matter by living organisms.


A fine threadlike structure of cell formed by fungi affecting a plant.

Incidental organisms

Organisms that have little or no impact on crop production.

Inhalation exposure

Pesticide is absorbed by breathing-in through the lungs.

Integrated Pest Management

An approach to pest management that uses a variety of techniques to identify and if necessary manage a pest.


Planting more than one crop in an area at the same time.

Interplanting (companion planting)

Growing two or more plants together in a close association.

IR mulches

Mulches that allow infrared radiation to penetrate through the mulch but reflects photosynthetically active radiation.


Dose required to kill 50% of laboratory test animals.


The downward movement of water and nutrients from the soil surface to the water table due to gravity.


Small (less than 1/2 inch long) wedge-shaped slender insects that disperse rapidly when disturbed.

Leggy or spindly

Excessive and weak stem growth due to exposure to adverse environmental conditions.


Plant that has a symbiotic relationship with rhizobium bacteria.

Light soil

A soil that contains a high proportion of sand.


Structures that occur where the leaf blade attaches to the stalk.


The overall climate of a particular region.

Maximum temperature

The warmest temperature that germination occurs for seed of a particular vegetable.


The specific environmental conditions of your garden site.


Plant nutrients that are needed in very small quantities.

Milk phase

Stage of development when the juice of the kernels on sweet corn ears appears milky.

Minimum temperature

Coolest temperature that seed germination or growth occurs for a particular vegetable.

Mixed fertilizers

Fertilizers that ontain the major nutrients (nitrogen, phosphorus and potassium).


A layer of material covering the soil surface to exclude sunlight.


A melon that has a musky aroma and salmon to orange colored flesh when mature. It has a netted rind with deep sutures.


The network or mass of hyphae formed by fungi.

Natural mulches

Mulches made from natural materials such as compost or bark.


The form of nitrogen that plants use. It is easily lost through leaching.

Noxious weed

Weeds that government agencies want to prevent from establishing in a particular area.

Nurse plants

Plants that provide factors or serve as breeding grounds for beneficial insects, increasing populations of beneficial insects.

Open-pollinated cultivars

Plants that are left to become pollinated on their own.

Optimum temperature

The temperature at which the greatest or most rapid seed germination occurs for a particular vegetable.

Oral exposure

Pesticide is ingested through a person's mouth.

Organic matter

Decaying plant, microbe and animal remains.

Organic pesticides

A pesticide made from a natural product that has undergone only a little processing.

Over mulching

Applying too much mulch.

Oxygen starvation

Roots cannot get the oxygen they need.

Paper mulches

Mulches made from newspaper or paper fibers.

Peat moss

The partially decayed remains of sphagnum moss.


Plants that live two or more years.


Lightweight volcanic material often used in soil less media.

Permanent wilting point

The point where a plant can no longer remove the small amount of water remaining in the soil and the plant wilts.


Plants, fungi, bacteria, nematodes, insects and animals that occur in a place they are not wanted.


A chemical that kills undesirable plants, plant diseases, insects or other pests.


Is – Log [H+] and a scale from 1 to 14.


The form of phosphorus used by plants.

Photodegradable mulch

Mulch that contains chemicals that cause the plastic to degrade when exposed to ultraviolet radiation.

Photosynthetically active radiation

Wavelengths of radiation (mostly reds and some blues and yellows) used by plants for photosynthesis (production of sugars).

Pickling cucumbers

Cucumbers that are one to six inches long with a warty skin that is used for pickling and sometimes for salads

Plant cages

Structures made from cloth or plastic that keeps out migrating insects while allowing sunlight, rain and wind to enter. They generally do not protect against cool temperatures.


A variety of corn that has small ears, kernels that are pointed at the base and apex and very hard starch in the kernels which explodes when heated.


A form of potassium contained in the soil and fertilizers and utilized by plants.

Preventative weed control

Practices whose aims are to prevent weeds from occurring in the garden.


Preventing problems before they occur.


The edible fruit of any Cucurbita species that is harvested mature and is not used as a baked vegetable.


The seed is true to type and does not contain undesirable contaminants.

Raised beds

Mound the soil up in the planting area above the surrounding soil level.

Re-entry time

The amount of time you must wait to enter a garden after it has been treated with a pesticide.

Rhizobium bacteria

Bacteria that grow in close association with the roots of legumes and can convert atmospheric nitrogen into nitrate.

Rock phosphate

A finely ground natural rock powder that is used to supply the soil with phosphate.


Removal of diseased plants.

Root resistant cultivars

Vegetable cultivars that are resistant to one or more disease, insect, nematode or virus.


A disease that attacks plant roots causing them to rot.

Row covers

Plastic sheets that can be used to cover rows of a crop and provide protection from cold temperatures and some insect pests.

Row planting

Growing vegetables in single or double rows with aisles between each row.


Soil particles ranging in size between 0.2 to 2 mm.


Removing sources of pests so as few pests as possible get into your garden.


Regularly checking crops for pests and damage symptoms; looking in your garden to determine if pests are a problem.

Seaweed meal

Seaweed that has been dried and ground into a fine powder. It contains many different compounds that may affect plant growth.


A dormant undeveloped plant.

Seed coat

The outer "skin" on a seed that protects it from the environment.

Seedless watermelon

Self-sterile watermelon hybrids that develop normal looking fruits, but no fully developed seeds.

Semi-organic or organically based

An organic fertilizer that has had potassium sulfate added.

Side dress

The process of applying soil amendments or fertilizers next to an emerged vegetable crop.


Applying fertilizer in a band near the crop row after the crop has emerged.


Soil particles between 0.002 and 0.05 mm in size.

Slicing cucumbers

Cucumbers that are 8 to 14 inches long with dark skin and used for salads, sandwiches, and soups

Soil crust

A hard surface layer that can form on some soils after rains.

Soil texture

The coarseness or fineness of soil particles.

Soil-less media

A growth media not containing field soil.

Soluble salts

Chemical compounds, many plant nutrients, that disassociate into positively and negatively charged ions.

Starch-based biodegradable mulch

Mulch made from plastic that contains starch, which is degraded by bacteria.

Succession plantings

Growing crops so that they mature at different times.

Sugar enhancer sweet corn cultivars

Cultivars that contain the sugar enhancer (se) gene, which significantly raises the sugar content of their kernels above standard cultivars.

Sugary sweet corn cultivars

Cultivars that contain the "sugary gene," have less initial kernel sugar than other sweet corn types, and that sugar is rapidly converted into starch after harvest.

Summer annuals

Weeds that germinate in the spring, grow during the spring and produce seed during the fall.

Summer squash

Squash whose fruit is harvested when immature before the rind hardens.

Supersweet cultivars

Cultivars that contain the shrunken-2 (sh2) gene which slows the conversion of sugar to starch, allowing these cultivars to hold their sweetness much longer than su or se types.

Sweet corn

Types of corn that produces and retains large amounts of sugars in its kernels, the skins of the kernels are tender and wrinkle when dried.


The outward appearance of a plant, which is attacked by a disease or insect.

Synthetic fertilizers

A fertilizer whose nutrients are concentrated and converted into a form that is readily available in the soil.

Synthetic mulches

Mulch from a man-made product such as plastic.

Synthetic pesticides

A pesticide synthesized from petroleum – derived chemicals.


The structure at the tip of the corn plant, which is the male flower.


The uppermost and the darkest layer of the soil that contains most of the organic matter, living organisms and plant roots.


Inherent capacity of a material to produce death or injury.


Shifting of a plant from one soil or growth medium to another.

Trap crops

Plants that attract insect pests keeping them away from the vegetable crop.


The plants are actually the vegetable and variety the label indicates.

Unmixed fertilizers

Fertilizers that contain only one plant nutrient


A botanical subdivision within a species.


Lightweight expanded mica often used in soil-less media.


The percentage of seed that will germinate.

Vine crops

Crops that produce vines that grow along the ground including watermelon, muskmelon and pumpkins.


Particles containing DNA or RNA that are much smaller than bacteria and require a host cell to multiply.

Warm season vegetables

Vegetables that germinate and grow best when temperatures are warm.


The air spaces in the soil are filled with water.

Wheel hoe

An oscillating or stationary hoe blade mounted on a wheel with handles.

Winter annuals

Germinates during the fall, overwinters and produces seed during the spring.

Winter melons

Melons that have a smooth rind surface, do not separate from the vine when ripe and lack a distinctive flavor.

Winter squash

A squash whose fruit are harvested when uniform in color and rind is hard.


A squash whose fruit is harvested immature, have a green colored skin and are long cylindrical-shaped with little or no taper.