Illinois Field Crop Applicators Practice Test

Which pest is known for causing heads of wheat to fall off?

1. Stalk borer

2. Armyworm larvae

3. Potato leafhopper

4. Corn rootworm

The correct answer is: Armyworm larvae

The armyworm larvae are known for causing significant damage to wheat crops, particularly during the critical reproductive phase. These larvae are voracious feeders that can consume the heads of wheat plants, leading to lodging, where the heads may fall off. This feeding behavior not only affects the yield but also reduces the quality of the grain, making it unmarketable. In contrast, the other pests listed impact crops in different ways. The stalk borer primarily damages the stalks of various crops and does not typically cause the heads of wheat to fall off. The potato leafhopper affects crops by sucking sap from the leaves, leading to discoloration and potential yield loss, but it does not directly cause heads to fall off wheat. The corn rootworm targets the roots of corn plants, causing stunted growth and lodging in corn, but it does not interact with wheat in the same manner as armyworm larvae. Understanding the specific damage caused by these pests helps in developing targeted pest management strategies.