 |
Field and Forage Crops |
Thrips pressure is now down considerably, although significant rainfall is still desperately needed in many areas. Plants are still pretty beaten in many cotton fields. Terminals of cotton plants in areas of good moisture are developing quickly.
Spider mite populations have continued to increase this past week, with some pesticide spraying underway. Some eastern counties of North Carolina received significant rainfall earlier, which should be a big help in reducing these pests which love dry weather. Remember that spraying is not advised until mites are both widespread in a field, the cotton is under stress, and that some defoliated has begun.
Based on budworm levels in other states and our high number of degree days at this point in the season, expect our initial budworm flights to occur sometime around June 15 in the southern part of North Carolina. Scouts should be inspecting terminals and squares for budworms and their damage in the southern counties. These counts should be done concurrently with square retentions counts for plant bug damage assessments. More information on these tobacco budworms and plant bugs will be provided in next week's issue of North Carolina Pest News.
Thrips continue to infest peanuts throughout the production area. Plants with tomato spotted wilt virus are also showing up in many fields. The threshold for follow-up foliar insecticide sprays remains at a level when 25 percent of the newly-opened leaflets show significant thrips injury. This threshold is based upon the direct impact of thrips feeding on the peanut plant and is not related to the transmission of tomato spotted wilt virus. Unless the thrips populations are high enough to threaten the crop (greater than 25 percent of the new leaflets with damage), do not use additional foliar insecticide sprays in hope of reducing the eventual level of tomato spotted wilt virus you will encounter.
The hot and dry weather in many areas makes this a prime year for spider mites and we do not want to encourage their presence with unnecessary foliar insecticide sprays. Keep a close watch for sites with spider mite injury as the season progresses. It is certainly possible we could see spider mites in peanuts by late June if the weather doesn't help us. Scout the traditional locations where mites are often seen.
Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age or disability. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.
Last modified on June 17, 2002 by Stephen J. Toth, Jr.