The Virginia distribution maps for these two invasive species are attached (please click “More”). Additional information: sep5distributionmaps-pdf

Please click “More” to view the Aug. 22, 2013 distribution map of kudzu bug in Virginia soybean and other hosts. Also in the attachment is the percent control of a long list of insecticides for kudzu bug (courtesy of Jeremy Greene at University of Georgia and Phillip Roberts at Clemson University). If you are at kudzu bug threshold (1 nymph per sweep) and decide to treat your field, you may want to consider a product (or one with similar active ingredients) from the list that has a high percent control. When choosing a product, please keep in mind any other pests that are present in your field. And, please read and follow the label. Additional information: kudzu-bug-distribution-va-2013-pdf

Please click “”More”” to view the most recent update on BMSB distribution in Virginia soybean (please see slide 1 of the attached pdf document). On August 20, our soybean scout Ed Seymore reported that in the last week stink bugs have started to move out of corn and into soybean fields in the counties of Culpeper, Fauquier, Franklin, King George, Rappahannock, Rockingham, Spotsylvania and Stafford. These counties have reached the threshold for stink bugs of 5 stink bugs in 15 sweeps (in the fields that we scouted). Attention should be paid to fields that border corn and woods especially with the tree of heaven (end report from Mr. Seymore). Note that thresholds in soybean do not distinguish between BMSB and native green and brown stink bug species (also shown on slide 1). Dr. Herbert’’s insecticide efficacy trials and on-farm edge treatment research suggest that most insecticides provide initial stink bug knock down (please refer to slides 2 and 3 for efficacy trial results, where the higher percent control, the better). Residual activity varies, and reinvasion can occur after loss of residual protection. Since BMSB exhibit a strong soybean field edge preference, perimeter-only treatments may be effective. Please remember to always base management decisions on proper scouting and thresholds, and always read and follow the pesticide label (sometimes, products and/or rates that we include in our tests are experimental; also, product labels and rates may change from year to year). Additional information: bmsb-pdf

I just got a report of a soybean aphid infestation in Essex County. It has been several years since we have seen soybean aphid in Virginia, but the summer conditions (generally cooler, overcast) favor development of that pest. Reports of spotty infestations are also coming in from other states, North Carolina included.

As a reminder, the current economic threshold for aphids is an average of 250 aphids per plant, on two consecutive field visits spaced about 5-7 days apart (hit the ‘more’ button for more). This is because aphid populations can ‘crash’ quickly due to heavy pressure by natural enemies like lady beetles, parasitic wasps, and fungal diseases. When scouting, choose a ‘Z’ or ‘W’ shaped pattern to cover the entire field and sample at last 20 to 30 plants per field by examining the entire plant including stems and upper and lower leaf surfaces. Use the aphid/plant average for determining the need for treatment. The threshold applies to soybean through the R5 growth stage (3 mm long seed in the pod at one of the four uppermost nodes on the main stem), after which time plants can tolerate 1,000+ aphids with no threat to yield.
Additional information: soybean-aphid-threshold-ppt