Illinois Field Crop Applicators Practice Test

What is an indicator of excessive damage caused by alfalfa weevil during a later cutting?

1. Feeding on 20% of stems

2. No regrowth for 3-6 days

3. Frost-like appearance of leaves

4. Discoloration of pods

The correct answer is: No regrowth for 3-6 days

The indication of excessive damage caused by alfalfa weevil during a later cutting is reflected in the observation of no regrowth for 3-6 days. This lack of regrowth suggests that the plants are under significant stress from the feeding activity of the weevil, which can severely impact their ability to recover. Alfalfa weevils primarily feed on the leaves, and when they cause extensive damage, the plant's health is compromised. Consequently, the regrowth process, which normally occurs after cutting, is delayed. This delay is a clear sign that the infestation has reached a level where it is affecting the plant's rejuvenation capabilities, making it a reliable indicator of excessive damage. In the context of the other choices, while feeding on stems could indicate some level of damage, it does not necessarily correlate with the excessive damage threshold that would hinder regrowth. A frost-like appearance of leaves is a symptom of environmental stress rather than damage specifically attributed to weevils. Similarly, discoloration of pods is not directly related to weevil damage in the context of the plants after cutting; it pertains to different types of plant stress or disease. Therefore, the absence of regrowth serves as a more definitive sign of excessive damage from the alfalfa