It seems that every year we see something new on pecans. This year I have seen two or three orchards suffering from May beetles feeding on the foliage. Normally even if you see a May beetle here or there in the orchard, its no cause for alarm but I have seen them devouring the buds and foliage of young trees this year. The white grubs of these beetles can be a problem in turf or other grass crops, but the adults will feed on a variety of broadleaf trees and shrubs.
We have seen them emerging primarily in new orchards that had previously been in pasture or pine trees. Early in the season they would chew the new buds off the tree. Lately they have been feeding on foliage. May beetles emerge from the soil at night to feed, then burrow into the soil under the trees to spend the day. Apply Chlorpyrifos in the herbicide strip and on the foliage to stop the damage.