By Jeremy Greene, Clemson Extension Entomologist
August 2, 2013
News from Above the Lakes
David DeWitt, county agent in the Pee Dee Region, reported that “it has been fairly quiet my way. Several are spraying some cotton but more out of habit than heavy pressure. Have seen and heard of some kudzu bugs but populations seem less than past two years. We had a lot (1000’s of acres) of soybeans not get planted because of rain…” He also asked if our insects will be bottlenecked into the acres we do have in the ground.
News from Below the Lakes
Charles Davis, county agent in Calhoun County, and Jonathan Croft, county agent in Orangeburg County, were with our new agent, Rebecca Hellmuth, in some cotton this morning in Orangeburg County and noticed some stink bugs and boll injury at threshold. They noticed high-clearance sprayers “in fields where they could get.”
Check fields for stink bugs. There are plenty out there. If fields are still in the 3rd to 5th week of bloom, they need to be aggressively protected against stink bugs. The dynamic boll injury threshold calls for treatment when boll injury meets or exceeds 10% during those weeks of bloom (WOB).
I just evaluated two efficacy trials for kudzu bugs this morning. Kudzu bugs were about the only pest species in those plots. We saw a few soybean loopers and stink bugs.
Bifenthrin (Discipline or Brigade in these trials) at either 4.0 or 6.4 fl oz per acre was very good as always. Products with other pyrethroid active ingredients (Warrior II, Hero, Endigo, Mustang Max, Endigo, Fastac, Declare, Cobalt Advanced, Stallion) produced acceptable control also. It appeared that Carbine and Transform were misses on kudzu bugs at 3DAT1.
Bollworm & Tobacco Budworm
Captures of bollworm (BW) and tobacco budworm (TBW) moths in pheromone traps at EREC this season are shown below, as are the captures from 2010 to 2012 for reference. Tobacco budworm continues to be important for our soybean acres and for a very limited number of non-Bt-cotton acres. I provide these data as a measure of moth activity in our local area as an indication of moth presence and activity near my research plots. The numbers are not necessarily representative of the species throughout the state.
Click Image to Enlarge
Click Image to Enlarge
I think our patterns of capture are looking like those experienced in 2010. If you remember that year, we had significant pressure from bollworm. We also had high numbers of tobacco budworm in the system that year. Captures of tobacco budworm moths are also looking to be high to end this season. Check soybeans for them.
I put together the precipitation total that we have had here at Edisto for 2013. That and the long-term average for Blackville, SC, are shown in the table. Although we have received a surplus of rain, we have been more fortunate than other areas of the state that have received significantly more rain. We are approaching a year’s worth of rain here at EREC, and other areas of the state have already exceeded their long-term yearly average!