What is in this article?:
- Upper Southeast cotton growers brace for thrips invasion
- New product not available
- Expensive materials
• The major variable on how much damage thrips cause is largely dependent on the weather and the size and timing of thrips flights into cotton fields.
• In terms of yield differential, Herbert says over the past 10 years thrips-related yield loss in Virginia has averaged about 380 pounds of lint per acre.
• In North Carolina, average losses are about half that amount.
NORTH CAROLINA State University Entomologist Jack Bacheler discusses thrips management.
Radiant and Benevia will likely be significantly less disruptive against beneficial insects that help manage aphids and mites. The major downside of these materials is their prohibitive $20-30 per acre costs at the rates tested.
“This year’s series of tests in Virginia and North Carolina will evaluate the effectiveness of several rates of these insecticides in the hope that one or both may give us an additional tool in minimizing our annual thrips dilemma,” Bacheler says.
Herbert and Bacheler have a long history of battling thrips and a well-deserved reputation as ‘thrips killers.’ Both contend thrips, even high populations on early planted cotton can be managed, but not without a lot of scouting and timely applications of pesticides.
Among the tools to be tested in 2012 are several high rate options of several materials that are currently labeled for use on cotton.
Another option will be the presence of multiple insecticides and nematicides on the same seed. One example for 2012 will be the Aeris/Poncho/VOTiVO option containing two nicotinoids and a conventional and biological nematicide.
Bacheler and Herbert tested several new in-furrow sprays for thrips control in 2011. Research findings were varied, but preliminary results, based on one-year of data, indicated Admire Pro (an imidacloprid) provided the extended five-week control researchers are seeking.
Research at Wilson, N.C., and at the Tidewater Agriculture Research and Extension Center in Suffolk, Va., showed good results using this material in the furrow.
Despite an impressive arsenal of thrips killing tools and years of experience managing these tiny yield-busting critters, growers are still faced with exactly what to do to prevent damage.
For the 2012 growing season, Bacheler says growers should use Temik, if they can find any, on early planted cotton.
Temik is still legal to use, but only carryover supplies from the 2010 season are available, though some growers stored a supply once they learned it would be taken off the market.
The second thing growers should do this year, the North Carolina State entomologist says, is to try to base follow-up foliar sprays behind seed treatments, based on terminal damage assessment and to plant a portion of total acreage between May 15 and May 25 to shorten the thrips susceptibility window.
Though early indications are for heavier than usual thrips populations this year, weather changes can have a huge effect on moth flights and subsequently thrips pressure. However, even in ‘good’ thrips years, the heart of Virginia-Carolina cotton country is likely to live up to its reputation as Thrips Central.
(For additional comments from Jack Bacheler on thrips control in North Carolina and Virginia, see http://southeastfarmpress.com/cotton/thrips-big-start-virginia-north-carolina).