SWD Update August 24

This post contains a summary of trap counts for the week of August 20. 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.

Overall, the number of SWD increased  from last week.

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 crops into stone fruit (peach, nectarine, blue plum) and grape varieties.  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.   Because the impact of SWD on peaches, nectarines, plums and grapes has not been confirmed in Ontario, it is recommended that when choosing pre-harvest insecticides for Oriental fruit moth or Grape berry moth, that products that also have activity against SWD be used if possible.  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.