Cotton Insect Newsletter Vol. 20, No. 1, May 22, 2002 Call 1-877-629-1474 for Cotton Insect Hotline

Cotton Situation:  Planting is probably about 80-90% complete.  The last few nights have seen low temperatures in the upper 40's and highs from 65-70 - - not very good cotton growing weather.  Growth stages range from seed in the ground, up to 6-7 leaf cotton.   Cotton fields with cotyledon to 3-leaf stage plants are most commonly encountered at this time. Insect Situation: Thrips are the greatest problem facing cotton seedlings this week.  Most of the wheat fields have dried down to the point where the bulk of the thrips have moved out in search of new hosts.  The peak movement probably occurred before May 15 this year, but there will more than likely be significant numbers of thrips available to infest cotton for the next couple of weeks.  I looked at a field on May 20 with an average of about two thrips per cotyledon-stage plant.  One thrips per plant is the treatment threshold up to the third-leaf stage.  The cool temperatures that are holding back cotton growth will also allow thrips to gain the upper hand.  Growing points will be damaged by thrips feeding in the tiny terminals, and maturity may be delayed for up as much as 2-3 weeks in the worst cases.  I have already seen some thrips damage bordering on plant death where no insecticide was used at planting in my thrips-control test.  Don't assume you have a thrips problem.  Start looking at plants prior to unfolding of the first true leaf for adult thrips and damaged terminal buds.  Seedling diseases are complicating the situation, as we are seeing more problems with both Pythium and Rhizoctonia than usual both at the PDREC and in on-farm observations.  Beet armyworms are showing up in rather high numbers in some fields.  Generally, these infestations will not be serious enough to require insecticidal protection.  Beneficial insects, such as big-eyed bugs, will usually do a pretty good job of knocking the beets out before they can inflict any serious damage. Grasshopper reports have been plentiful this spring.   Where growers are planting strip-till cotton, eggs may have been laid directly into the fields that are being planted.  When the cotton seedlings break the ground, there are some hungry hoppers waiting for them.  Insecticide Recommendations: The newest edition of “Cotton Insect Management,” IC-97, is now available.  If you haven't received one in the mail, pick it up at your County Extension office.  Several changes are made to the recommendations each year, so don't use those published before 2002.   The “Pest Management Handbook” can be accessed at the Clemson University Coop Extension website:  http://cufan.clemson.edu/pestmgmtguide/.  Cotton Scouting Schools: Well here we go again, time for scout training.  This year two schools will be held, one at the PDREC on June 5 and the other at Orangeburg-Calhoun Technical College (room 1512, in the auditorium nearest the hospital) on June 6. The program at each site will be similar to the following schedule of topics: 8:00 to 9:00 AM....Registration 9:00....Cotton Production      * Growth and development of cotton plants      * Production techniques 9:30 ....Insects that Damage Cotton       * Growth and development of insects       * Identifying common insect pests        * How insects damage the cotton plant  11:00 ...Weeds and Herbicide Injury to Cotton:      * Identifying the most troublesome weeds in cotton      * Characteristics of seedling plants useful in identifying weeds      * Symptoms of herbicide injury 11:30 ...Diseases and Nematodes:      * Symptoms of common diseases and nematodes of cotton      * Seed rot      * Handling diseased plant specimens for diagnosis  12:00...Lunch on your own. 1:00 ...Beneficial Insects and Spiders:      * Identifying the common beneficials      * Protecting honey bees 1:30 ...Scouting Methods:      * Techniques used to scout for insect pests       * Determining threshold levels for control of insect pests      * Equipment needs 2:15....Pesticides and Safety:  3:00-4:30....Summary and Field training (if weather permits)      Mitchell Roof  Extension Entomologist

This information is supplied with the understanding that no discrimination is intended and no endorsement by the Clemson University Cooperative Extension Service is implied. Brand names of pesticides are given as a convenience and are neither an endorsement nor guarantee of the product nor a suggestion that similar products are not effective. Use pesticides only according to the directions on the label. Follow all directions, precautions and restrictions that are listed. The Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, sex, religion, national origin, disability, political beliefs, sexual orientation, marital or family status and is an equal opportunity employer.  Clemson University Cooperating with U.S. Department of Agriculture and South Carolina Counties.  Issued in Furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of May 8 and June 30, 1914.  Public Service Activities