Iowa Commercial Pesticide Applicator Category 1A Exam Questions and Answers 100% Pass

Iowa Commercial Pesticide Applicator Category 1A Exam Questions and Answers 100% Pass What is the greatest hazard when applying most herbicides? - Answer- Injury to nontarget plants Name some herbicides which are very effective against germinating weeds but less effective on established weeds. - Answer- Frontier, Lasso, and Dual What soil conditions reduce the activity of many herbicides and require increased rates for adequate weed control? - 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 - Answer- Sencor and Lexone Where are high pH soils most common in Iowa? - Answer- Next to limestone and gravel roads Two herbicides that are more persistent and likely to carryover residues. - Answer- Atrazine and chlorimuron What factors can increase chances of herbicide carryover? - 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? - 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? - Answer- Rainfall or irrigation