As of Aug. 11, 2014, the USDA NASS South Carolina Statistical Office estimated that about 83% of the crop has bloomed, compared with 48% this time last year and 67% for the 5-year average.
About 20% of the crop has set pods, compared with 13% this time last year and 30% for the 5-year average. The soybean crop was described as 4% excellent, 62% good, 31% fair, 3% poor, and 0% very poor.
These are observed/perceived statewide averages.
Insects
Thresholds for numerous species that can be found in soybeans right now are (on 38″ row spacing):
Defoliators (SBL, VBC, grasshoppers, etc.)
- 15% defoliation
- 6-8 large SBL/rowft; 4-6 large VBC/rowft
Pod Feeders (stink bugs, corn earworm, etc.)
- 1 stink bug/rowft or 1/10 sweeps
- o 2+ CEW/rowft
Stem Feeders (kudzu bugs, TCAH, etc.)
- 1 kudzu bug nymph/sweep
- 3 TCAH/rowft
It is imperative that you can identify the caterpillar species present in soybeans. After some experience, you will be able to identify the moths you are “flushing” in the field, and you will know what species is trying to colonize the field…predicting the future! Maybe…possibly…that’s the idea.
SWEEP NET THRESHOLDS
Sweep net thresholds in drilled soybeans are not as well-defined as those for beat/shake samples. The following thresholds should be considered guidelines until more research is available. Use percent defoliation estimates as an additional treatment guideline for foliage feeders. Prior to bloom, up to 30% defoliation is acceptable without economic yield loss, but once blooming begins, the guideline drops to 15% defoliation.
