There have been a few reports of armyworm damage on corn planted after a small grain cover crop or in dense weed growth. This is not out of the ordinary for this time of the year. But it does make you wonder what is happening in wheat. I’ve noticed some lodging of wheat from recent storms. These lodged area are some of the first places I would monitor for signs of armyworm feeding. We normally thing of armyworms feeding on leaves but once the small grain has headed, armyworms can/will clip the stem off just below the head. 

 

There have been some reports of slug feeding and a few of those reports have indicated severe injury. The cool, rainy weather we’ve had is very favorable to slug survival as is the presence of crop residue or weed growth. Given the value of corn it could be worth the time and effort to spot check likely areas. Although there is not a lot of threshold information available for slugs, I would suggest that you take into consideration the size of the crop and future growing conditions before treating. I would have a hard time suggesting treatment if feeding is concentrated on the lower leaves of corn that is growing rapidly. Especially if good growing conditions are predicted and there are no other reasons to think the crop is stressed.  If the reverse is true I could feel more comfortable treating if weather conditions were to remain cool and cloudy. Remember that slugs are not controlled by insecticides. The use of appropriately labeled slug baits is sometimes an economical, if not temporary solution. Control may be reduced if rains breaks down the bait. and cool growing conditions (that are favorable to slug survival) persist. The best control method is warm, sunny weather that not only hastens corn growth but also increases slug mortality.