Some pests continue to feed on small grains, corn and soybeans.
As we have mentioned in past weeks, growers would be wise to stay alert for cereal leaf beetle in small grains. Populations are quite variable across the state, but some fields are hosting large populations of cereal leaf beetle larvae. These larvae have been mistaken for slugs because they look slimy (they store their feces on their back to protect themselves from predators), but slugs are nocturnal and cereal leaf beetle larvae are diurnal. This pest is most easily controlled when larvae are young, so scout your fields to understand your local populations. For images and details on this pest’s life cycle and management options, see our recently revised fact sheet.
Speaking of slugs, it is also that time of year to watch for these annoying mollusks. With the cool temperatures that we have experienced recently, slugs damage can appear quickly and the rain that many parts of the state are experiencing today will make slugs happy. However, the coming warm weather should slow down slug activity and push crops along, minimizing the threat posed by slugs. If you have questions about slugs or their management, see our new regional slug resource.
Lastly, as a reminder, Penn State’s Black Cutworm Monitoring Network detected “significant flights” of black cutworm moths near St. Mary’s (Elk County), Wellsboro (Tioga County), and Mercer (Mercer County) and Kutztown (Berks County). Significant flights occur when we capture in an individual trap eight moths over the course of two nights, we can then predict that a significant population may develop and that cutting larvae will be active in that area in approximately 300 degree days. Degree-day accumulations for black cutworm can be visualized with the PA-PIPE system. As of this morning, degree-day accumulations are 186 for St. Mary’s, 154 for Wellsboro, 226 for Mercer, and 105 for Kutztown. With warm weather expected in the coming week, the 300 degree-day threshold will likely be exceeded shortly, so scout those fields for black cutworm damage in the coming days. Remember that well-timed scouting and spot rescue treatments are usually the most economical strategy for managing black cutworm. For more details on black cutworm, its biology and management options see our fact sheet.
Source : psu.edu