HERBICIDES AND WEEDS - CHAPTER 3 RIGHTS-OF-WAY
(PESTICIDE APPLICATOR LICENSE) EXAM QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS VERIFIED
plant characteristics, climate, characteristics of the herbicidal action
factors that affect how a plant will respond to herbicide
foliage absorbed herbicides
herbicides enter the plant through the leaves
root absorbed herbicides
herbicides enter the plant through the roots and are generally more effective when
applied preemergence
contact herbicides
only kill the green portion of the plants where the herbicide directly contacts the weed.
most are nonselective and are effective in controlling annual and biennial weeds, and
provide temporary suppression of perennials
systemic (translocated) herbicides
herbicides that travel throughout the plant, whether foliar or root absorbed. these
herbicides are especially useful for perennial weed control because they move into the
roots
persistent herbicides
remain active in the environment for an extended period of time
nonpersistent herbicides
, relatively short-lived herbicide. time is greatly influenced by temperature, sunlight,
moisture, soil type and rate of application
selective herbicides
kills specific weed pests and does not kill surrounding vegetation
nonselective herbicides
remove most or all vegetation
growing points
if they are sheathed or located below the soil surface, they will not be reached by
contact herbicide sprays
leaf shape
herbicides tend to bounce or runoff narrow, upright leaves. broad, flat leaves tend to
hold the herbicide longer
wax and cuticle
foliar sprays may be prevented from entering the leaf depending on the thickness of...
leaf hairs
hair like structures that, if long, hold herbicide droplets away from the leaf surface,
allowing less chemical to be absorbed into the plant. if they are short it holds the
droplets close to the surface, allowing them to be absorbed better.
deactivation
certain plants can turn off the herbicides and are less susceptible to injury from the
chemicals
stage in life cycle
(PESTICIDE APPLICATOR LICENSE) EXAM QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS VERIFIED
plant characteristics, climate, characteristics of the herbicidal action
factors that affect how a plant will respond to herbicide
foliage absorbed herbicides
herbicides enter the plant through the leaves
root absorbed herbicides
herbicides enter the plant through the roots and are generally more effective when
applied preemergence
contact herbicides
only kill the green portion of the plants where the herbicide directly contacts the weed.
most are nonselective and are effective in controlling annual and biennial weeds, and
provide temporary suppression of perennials
systemic (translocated) herbicides
herbicides that travel throughout the plant, whether foliar or root absorbed. these
herbicides are especially useful for perennial weed control because they move into the
roots
persistent herbicides
remain active in the environment for an extended period of time
nonpersistent herbicides
, relatively short-lived herbicide. time is greatly influenced by temperature, sunlight,
moisture, soil type and rate of application
selective herbicides
kills specific weed pests and does not kill surrounding vegetation
nonselective herbicides
remove most or all vegetation
growing points
if they are sheathed or located below the soil surface, they will not be reached by
contact herbicide sprays
leaf shape
herbicides tend to bounce or runoff narrow, upright leaves. broad, flat leaves tend to
hold the herbicide longer
wax and cuticle
foliar sprays may be prevented from entering the leaf depending on the thickness of...
leaf hairs
hair like structures that, if long, hold herbicide droplets away from the leaf surface,
allowing less chemical to be absorbed into the plant. if they are short it holds the
droplets close to the surface, allowing them to be absorbed better.
deactivation
certain plants can turn off the herbicides and are less susceptible to injury from the
chemicals
stage in life cycle
