National Core Manual - Chapter Seven

Question 1

Solubility

Answer 1

measure of the ability of a pesticide to dissolve in a solvent; usually water

Question 2

Adsorption

Answer 2

process whereby a pesticide binds to soil particles - attraction between the chemical and soil particles

Question 3

Persistence

Answer 3

ability of a pesticide to remain present and active in its original form for an extended period before breaking down

Question 4

Half-Life

Answer 4

description of persistence; comparative measure of the time needed for the chemical to degrade - longer the half-life; more persistent the chemical

Question 5

Residue

Answer 5

pesticide that remains in the environment after an application or spill

Question 6

Types of Pesticide Breakdown

Answer 6

chemical degradation, microbial action, photodegradation

Question 7

Chemical Degradation

Answer 7

breakdown of chemicals that do not involve living organisms, usually by a chemical reaction with water

Question 8

Microbial Action

Answer 8

breakdown of chemicals by soil microorganisms, such as fungi or bacteria

Question 9

Photodegradation

Answer 9

breakdown of chemicals in reaction to the sunlight

Question 10

Volatility

Answer 10

tendency of a pesticide to turn into a gas or vapor; increases as temps and wind increase, more likely in low humidity

Question 11

Volatility Increase Factors

Answer 11

high temps, high winds, low humidity

Question 12

Drift

Answer 12

pesticide movement away from the application site by wind or air current

Question 13

Runoff

Answer 13

pesticide movement in water by surface movement off the treated site

Question 14

Leaching

Answer 14

pesticide movement by downward flow through the soil

Question 15

Runoff / Leaching Risk Factors

Answer 15

applying or spilling too much, too much rainwater or irrigation, use of highly soluble or persistent pesticides

Question 16

Spray Drift

Answer 16

off target movement of a pesticide during a liquid application

Question 17

Avoiding Spray Drift

Answer 17

pay attention to spray droplet size, wind direction and wind speed

Question 18

Decreasing Outdoor Drift

Answer 18

spray in winds less than 10 mph, spray downwind from sensitive areas, use proper nozzles and pressure, use drift control additive where possible, lower boom height, leave an untreated buffer area in the downwind target area

Question 19

Temperature Inversions

Answer 19

can cause extensive drift over long distances, air at ground level is cooler than the air above it - causes sideways air movement and therefore longer drift (often seen in the early evening)

Question 20

Vapor Drift

Answer 20

the movement of pesticides as gaseous vapors from the target area; volatilization caused by hot weather creating drift

Question 21

Particle Drift

Answer 21

AKA Dust Drift; the movement of solid particles from the target area in the air during or just after application

Question 22

Point-Source Pollution

Answer 22

comes from a specific, identifiable location

Question 23

Nonpoint-Source Pollution

Answer 23

comes from a widespread area

Question 24

Saturated Zone

Answer 24

the layer of soil, sand, gravel or fractured bedrock in which all available spaces are filled with water

Question 25

Water Table

Answer 25

the boundary between the saturated zone and the overlying unsaturated rock

Question 26

Aquifer

Answer 26

overall geologic formation from which groundwater can be drawn

Question 27

Four Soil Properties that Affect Leaching

Answer 27

texture & structure, organic matter, depth to groundwater and geology

Question 28

Soil Texture

Answer 28

relative proportions of sand, sild and clay sized particles

Question 29

Coarse Soil Texture (Leaching)

Answer 29

sand; low organic matter content means faster water flow and little adsorption - HIGH PERMEABILITY

Question 30

Smooth Soil Texture (Leaching)

Answer 30

clay, silt; high organic matter content, higher water retention, greater adsorption of pesticides - LOW PERMEABILITY

Question 31

Preventing Surface & Groundwater Contamination

Answer 31

use IPM principles, identify vulnerable areas, do not mix & load near water, keep pesticides away from wells, avoid back-siphoning, improve application methods, time appropriately with weather, use / handle products wisely

Question 32

Back-Siphoning

Answer 32

the reverse flow of liquids into a fill hose

Question 33

Outdoor Sensitive Area Examples

Answer 33

schools, playgrounds, endangered species habitat, apiaries, livestock areas, public gardens

Question 34

Indoor Sensitive Area Examples

Answer 34

hospitals, daycares, food / feed processing and preparation areas, domestic or confined animals, ornamental planting areas such as mall plantings