Download IOWA COMMERCIAL PESTICIDE APPLICATOR CATEGORY 1A EXAM | QUESTIONS & 100% CORRECT ANSWERS and more Exams Pest Management in PDF only on Docsity!
IOWA COMMERCIAL PESTICIDE
APPLICATOR CATEGORY 1A EXAM |
QUESTIONS & 100 % CORRECT ANSWERS
(VERIFIED) | LATEST UPDATE | GRADE A+
What is the greatest hazard when applying most herbicides? Correct Answer: Injury to nontarget plants Name some herbicides which are very effective against germinating weeds but less effective on established weeds. Correct Answer: Frontier, Lasso, and Dual What soil conditions reduce the activity of many herbicides and require increased rates for adequate weed control? Correct Answer: Higher levels of soil organic matter or clay Two herbicides which are more active on soils with a pH above 7.5 and can injure soybeans Correct Answer: Sencor and Lexone Where are high pH soils most common in Iowa?
Correct Answer: Next to limestone and gravel roads Two herbicides that are more persistent and likely to carryover residues. Correct Answer: Atrazine and chlorimuron What factors can increase chances of herbicide carryover? Correct Answer: Dry weather, high rates, late application, and in the case of some herbicides, high soil pH Can additive injury occur when applying Sencor/Lexone on soybeans in fields with atrazine carryover residues? Correct Answer: Yes What do preemergence herbicides rely on to move the herbicide into the weed seed germination zone (top 1/2-1 inch) of soil? Correct Answer: Rainfall or irrigation What tillage tools will improve weed control when rainfall does not occur soon after herbicide application, and weeds begin emerging? Correct Answer: Rotary Hoe and Harrow Name 3 herbicides which must be incorporated to prevent evaporation loss. Correct Answer: Sultan+, Eradicane, Eradicane Extra
Correct Answer: Because translocated herbicides move within the phloem, they can move both up and down a plant. Are Roundup, 2,4-D, Fusilade 2000, Poast Plus, Clarity, and Banvil contact herbicides or translocted herbicides? Correct Answer: Translocated herbicides What is essential when using contact herbicides? Correct Answer: Good spray coverage (usually involving high carrier volumes) When is the best time (in regards to maximum weed control) to apply contact herbicides to annual weeds? Correct Answer: When the weeds are small and actively growing Why are contact herbicides not great at controlling perennial weeds? Correct Answer: They only control the shoot, and cannot travel down to kill the root system resulting in regrowth When you are using translocated herbicides to control perennial weed root systems, when is usually the best treatment time? Correct Answer: Bud to bloom growth stage When applying Prowl, Banvel, and Clarity in a corn crop, what practice can cause injury
Correct Answer: Incorporation Why shouldn't you apply 2,4-D to corn from tasseling to brown silk? Correct Answer: Severe pollination injury can occur When does particle drift occur? Correct Answer: Small spray droplets move off target when they are applied, typically due to wind How can you reduce particle drift? Correct Answer: Use coarse sprays and drift control agents while avoiding application during windy conditions Which formulation of 2,4-D can drift in vapor form and which cannot? Correct Answer: Ester 2,4-D can vapor drift Amine 2,4-D cannot Why does Banvel have the possibility to vapor drift after it has been applied? Correct Answer: Banvel changes to volatile forms on plant leaves In Iowa, when is the general time of year when temperatures rise too high to apply Banvel Correct Answer: Mid-June
When should annual broadleaf leaves be sprayed in pastures? Correct Answer: Spring, after they have fully expanded leaves Why do many pasture herbicides have grazing restrictions? Correct Answer: To prevent the occurrence of illegal residues in meat or milk At greater than what soil pH level should you not use Canopy, Preview, and Lorox Plus due to carryover risk? Correct Answer: 6. What practice will reduce vapor drift risk of the herbicide Command? Correct Answer: Incorporation Within how many feet of towns and commercial fruit/vegetable production should you not use Command? Correct Answer: 1, What evironmental factors can increase the activity of postemergence herbicides and increase crop injury risk? Correct Answer: Increased temperature, humidity, and soil moisture What can occur as a result of harvesting crops before a labeled harvest interval elapses?
Correct Answer: Illegal crop residues Which type of weed can regrow from underground buds following tillage? Correct Answer: Creeping perennials When are biennial weeds most sensitive to herbicides? Correct Answer: During the rosette stage What factors reduce the likelihood of herbicide leeching? Correct Answer: Low solubility, short persistence, and strong absorption What can reduce the contamination of surface water by herbicides? Correct Answer: Grass buffer strips, terraces, conservation tillage, lower application rates Why are re-entry intervals required for pesticides such as Gramoxone Extra? Correct Answer: They are highly toxic to warm-blooded animals Repeated use of herbicides with the same mode of action can result in what? Correct Answer: Herbicide-resistant weed biotypes
