Ohio Pesticide Applicator Training
Field Crops
Student Workbook

Bulletin 821

1. What conditions(s) can increase the chance that corn will be attacked by armyworms?
1. Corn planted in fields adjacent to small grains
2. Planting corn after soybeans
3. Corn planted in a grass covered crop under a reduced-tillage program
4. All the above
5. Both A and C

Answer

2. Wireworms are the larval stage of which group of beetles?
1. Japanese beetles
2. Click beetle
3. Bean leaf beetle
4. Flea beetle development

Answer

3. What is the preferred method for preventing corn rootworm injury?
1. Rotation of corn with an alternate crop
2. Using insecticides
3. Planting corn after corn
4. None of the above

Answer

4. High organic matter, decaying vegetation, or cool, damp soil, are conditions where what insect can cause problems in corn?
1. Rootworm
2. Grubs
3. European corn borer
4. Seedcorn maggots

Answer

5. What stage of the alfalfa weevil causes the most damage to alfalfa foliage?
1. Adult
2. Pupa
3. Nymph
4. Larvae

Answer

6. The Hessian fly can be a problem when:
1. Wheat is planted after the Ohio fly-free date
2. The fall is hot and humid
3. Wheat is planted before the Ohio fly-free date
4. Wheat is planted following wheat

Answer

7. An insect that feeds on the corn foliage starting with the edge of the leaf and defoliates a plant completely to a point that only the leaf midribs remain is the:
1. Armyworm
2. European corn borer
3. Corn rootworm
4. Corn leaf aphid

Answer

8. During a walk through your corn field you find stalks of young corn cut off at ground level. What insect(s) could have caused this?
1. Sod webworm
2. Cutworm
3. Grubs
4. Both B and C
5. Both A and B

Answer

9. How do wireworms damage a corn stand?
1. By feeding on germinating seeds
2. By feeding on early seedlings
3. They may bore into stalks at the soil level
4. All the above
5. None of the above

Answer

10. As you drive down the road you notice some of your corn lodged over or "goosenecked." Upon closer examination, you also find several ears with the silks clipped off. What is the problem?
1. Raccoons
2. Rootworms
3. Japanese beetles
4. European corn borer
5. Both B and C

Answer

11. The most common insect pest(s) attacking the corn seed after planting are:
1. Wireworms
2. Seedcorn maggots
3. Grubs
4. All the above
5. Both A and B

Answer

12. The decision to apply a pesticide must be based on:
1. The economic cost-benefit of the action
2. The environmental implication of the action
3. Applicator safety
4. All the above

Answer

13. Soybeans become more sensitive to defoliation at what growth stage?
1. Emergence to bloom
2. Bloom to pod-fill
3. After pod-fill to plant yellowing
4. Plant yellowing and beyond

Answer

14. Honey bees are needed for pollination of our crops. During what time of day should we spray unwanted insects so that the honey bee will have a greater chance to survive?
1. During the middle of the afternoon
2. In early morning or late day when bees would not be active
3. Around noon
4. Just before a rain

Answer

15. Bean leaf beetles often can feed on soybean pods. When is rescue treatment warranted?
1. When injury to 10 percent or more of the pods is likely
2. When beetles are clearly visible in the field
3. When injury to 25 percent or more of the pods is likely
4. Treatment is not necessary after pods are set

Answer

16. In corn, what part of the plant do grubs prefer to feed on?
1. Roots and root hairs
2. Newly emerged foliage
3. The main shoot below ground level
4. Both A and C
5. Both B and C

Answer

17. Common stalk borer damage in corn is best prevented by:
1. Using resistant varieties
2. Not planting next to alfalfa
3. Maintaining weed-free fields
4. Treating seed prior to planting

Answer

Match the insect damage symptoms with the correct insect. Place the letter of the most correct insect on the line next to the plant symptom.
18. ____ Soybean foliage exhibits a speckled appearance and later may turn yellow or bronze
             A. Seedcorn beetle
19. ____ Partially eaten corn seeds; loss of germination or stunted seedlings
             B. Flea beetle
20. ____ Oblong holes in the corn; leaves in the pre-whorl stage
             C. Potato leafhopper
21. ____ "Windowpane" feeding in corn and 1/8 inch long, black insects that jump when disturbed
             D. Billbugs
22. ____ Stunting, leaf curling, necrosis or dying soybean leaves
             E. Two-spotted spider mites
23. ____ "Skeletonizing" of soybean leaves
             F. Mexican bean beetle

Answer

24. Timely cutting of alfalfa is an alternative to using insecticides for management of the alfalfa weevil or potato leafhopper.
1. True
2. False

Answer

25. Most black cutworms overwinter in plant debris from the previous crop.
1. True
2. False

Answer

26. The adult Japanese beetle is a problem during the months of April and May when soybeans are young.
1. True
2. False

Answer

27. Armyworms can attack either wheat or corn.
1. True
2. False

Answer

28. Several species of aphids can be found in Ohio wheat fields. None of them ever warrants rescue treatment.
1. True
2. False

Answer

29. Most chemicals used for insect control have no preharvest limitation, which means after spraying there are no needed waiting days for harvest or grazing.
1. True
2. False

Answer

30. Not all insects were covered by this test. It would be advisable to become familiar with all the insects listed in OSU Extension Bulletin 545 prior to taking the private applicator exam.
1. True
2. False

Answer

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture

All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.

Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.

TDD No. 800-589-8292 (Ohio only) or 614-292-1868