
Nicholas Seiter
IL Extension
nseiter@illinois.edu

Nicholas Seiter
IL Extension
nseiter@illinois.edu
NICHOLAS SEITER UPDATES



Earlier this week, I had the opportunity to visit a field with probably the worst grape colaspis injury I have seen. Note the phosphorus deficiency symptoms on the lower leaves of many plants and the aggregated nature of the injured plants. Usually, we see this in fairly isolated areas of a field—often at the high points—and several nearby fields had this more limited injury. But in this particular case, much of the field was affected. When you see this kind of injury above ground, dig up the plant and look for larvae, which resemble tiny white grubs. Some plants in this field had as many as eight or nine larvae on them, and we found at least one pupa. These should cycle out into adulthood soon.