Last week, Larry Bledsoe from Purdue University reported that corn rootworm hatch occurred on June 3 (seehttp://extension.entm.purdue.edu/pestcrop/2015/Issue11/). With the exception of 2012, this seems to be in line with past few years. The bad news is that these young larvae will start to munch on the developing corn roots. The good news is that the heavy recent rain we are receiving will help saturate the soils. This heavy moisture will tend to increase mortality of these very small larvae. How much mortality remains to be seen, and, although this can severely impact rootworm populations, feeding can still be observed. There are good management tools to protect against rootworm feeding, including transgenic hybrids. As most are aware of, rootworm resistance to some Bt proteins has occurred in parts of the Western corn belt. We have not seen any substantial evidence of resistance in Ohio. Regardless of your rootworm management tactic, it is always a good idea to dig roots later in July after larvae development is complete to determine how well the product performed.
Rootworm Hatch is Underway
Crop Observation and Recommendation Network
C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.