We’re experience a period of high insect activity this year, with rain, warm days, and cool nights providing an ideal breeding ground for three challenging pests: spotted wing drosophila (SWD), whose numbers began to explode in mid-July, summer beetles (especially Japanese beetles), and brown marmorated stink bug. Senior Extension Associate and entomologist Peter Jentsch of Cornell University’s Hudson Valley Laboratory recommends the following controls.
Spotted Wing Drosophila (SWD)
With raspberry, blackberry, strawberry, blueberry, and sweet and tart cherry all very susceptible to SWD, good management is a must. Follow these general rules:
- Traps are the best method for monitoring the population. Jentsch recommends making traps out of red plastic 16-ounce Solo cups and lids; get the directions here. Hang several traps in each crop.
- Sample fruit for infestation. Choose unripened fruit and look for evidence of egg laying and larval feeding: small holes with tiny white breathing tubes. When the berry is gently squeezed, it may leak juice. Infested berries may also leave a juice stain on their container when picked.
- Apply insecticide treatments from this Cornell-approved chart no more than seven days apart in blueberry, and every three to four days in cherry, raspberry, and blueberry. Reapply after rains. Rotate according to mode of action.
- Chill berries immediately after harvest—at 32 to 33 degrees F—to halt the development of larvae and eggs.
Japanese Beetles and Other Summer Beetles
Japanese beetles are considered one of the most devastating pests for 300 species of plant in this region of the country. Multicolored Asian ladybird beetle (MALB), the rose chafer (RC), adult plum curculio (PC) are also prevalent in the Northeast. Prevent them from feeding on foliage with:
- Carbaryl or Sevin, as a liquid XLR Plus, 4F or 80S powder.
- Leverage 2.7SE. According to Jentsch, this “should be reserved for those situations when the pest complex to be treated is appropriately matched to the combination of active ingredients and modes of action contained in the product.”
- Japanese beetle bag traps. These inexpensive traps, which use pheromones and floral scents, are very effective in luring and killing Japanese beetles. However, when placed near crops, they can encourage a large number of insects to move into the crop, causing even more damage. Jentsch warns, “If they are used, place the bags a considerable distance away from your orchard or vineyard so as to reduce the population in your crop. They will fill quickly and need to be emptied frequently.”
Brown Marmorated Stink Bug
A year-round pest, the brown marmorated stink bug (BMSB) is a household nuisance in winter and spring and a serious agricultural pest in summer and fall. It has been observed feeding and reproducing in blueberries, raspberries, blackberries, blueberries, and caneberries. BMSB causes discoloration and sunken areas of green fruits at the feeding site, and softening and necrosis in mature fruits. Control them with:
- Pyramid traps baited with BMSB aggregation pheromone and methyl decatrienoate. Because BMSB prefers to live along the perimeter of a field, place traps is along a forested edge adjacent to your crops.
- Employ border sprays, according to this chart, especially on large fields. Because the insecticides that are most effective on BMSB also kills the insect’s natural enemies, use them only as needed. As the BMSB SCRI CAP Small Fruit Commodity Team cautions, “Management for BMSB in small fruit crops is difficult because the most effective insecticides for BMSB cannot be used during the period when there are repeated harvests of berry fields. Chemical control may be further complicated by the need to conserve insecticides for use against spotted wing drosophila, another disruptive invasive species, during the harvest period in order to observe requirements for maximum applications per season.”
For further reading, visit the Jentsch Lab blog: