This past week, spotted wing drosophila (SWD) activity was confirmed in several new areas in Kentucky, (including Breathitt, Meade, Bourbon, Garrard, and Ohio Counties) based on trapping or infested fruit sampling. These new confirmations include some farms in central and eastern Kentucky, and they represent a rapid uptick in SWD activity. So far, 2014 appears to be very similar to what we experienced in 2013.
With SWD activity increasing, there are some things to consider.
1. The first consideration is: which small fruit crops are still vulnerable. Blueberries are close to the end of the harvest period, so this crop will likely escape serious losses to SWD. However blackberries are just beginning and producers should be monitoring for SWD in these fields and begin controlling SWD if it is detected. We also have fall red raspberries and grapes to be harvested. Red raspberries are very susceptible to SWD and some grapes varieties can be as well.
2. The other consideration is: SWD presence will vary from farm to farm. So, we strongly encourage producers to monitor for SWD as we have seen many farms without SWD activity. Trapping should occur on a farm-to-farm basis. Even within a county there can be farms with and others without SWD activity. If SWD is not detected, there is no reason to apply an insecticide during the harvest period, but SWD should be monitored on each farm growing susceptible crops.
For recommendations on management, see our fact sheets on the UK Entomology publications Web page.
Ric Bessin, Extension Entomologist