SWD Update August 17

This post contains a summary of trap counts for the week of August 13. The traps are shifting from berry crops to later stone fruit and early grape varieties.

Please refer to previous blog posts for counts from earlier in the growing season. The regional monitoring program is being conducted in berry and stone fruit crops and grapes in Essex, Chatham-Kent, Elgin, Norfolk, Niagara, Wellington, Durham, Ottawa/Carleton, Stormont/Glengarry/Dundas and Northumberland counties.

The monitoring project is a collaboration among the Niagara Peninsula Fruit and Vegetable Growers, Ontario Tender Fruit Growers, the Eastern Ontario Berry Growers, OMAFRA staff and private consultants.

Traps are being moved from harvested berry crops into stone fruit (peach, nectarine, blue plum) and early grape varieties (Baco and Pinot noir).  We have placed 3-4 traps with commercial SWD lures at each site.  Use these results in addition to your own monitoring program to determine when SWD is present on your farm. Conduct a salt water test or a plastic baggie test to confirm presence of larvae in fruit.

SWD has been identified in traps in all monitored counties.  There are conflicting reports about the susceptibility of stone fruit and grapes to SWD.  To be on the safe side, when spraying for later season insect pests (Oriental Fruit Moth, Grape Berry Moth), choose a product that has activity against both.This means that growers with ripening crops susceptible to SWD should consider using a product with activity against swd in preharvest sprays.  Check the SWD product registrations on our website. Mako and Malathion have received emergency use registration for this year again and previous blog posts for information on products for managing pre-harvest insects including swd on stone fruit and grapes.

F = female; M = male; PH = post-harvest