Spotted Wing Drosophila (SWD) Update – June 16, 2015

Spotted wing drosophila adults are active already. We have found low numbers of flies at sites in Essex, Norfolk Oxford, and Halton counties and Niagara and Durham region. This is about three weeks earlier than normal.

Degree day models for southern Ontario suggest that the overwintering generation of SWD is laying eggs in fruit. In earliest areas, the model predicts that the first generation of flies is beginning to emerge from infested fruit. Since the only fruit present right now is strawberries and haskaps, these crops are theoretically at risk. We do not normally see damage on strawberries and haskaps until after the June harvest is over, so I am reluctant to suggest special sprays for SWD at this time. However, watch closely for signs of premature breakdown and poor quality of these crops. (Figure 1) . Keep all ripe fruit harvested on a tight schedule, and refrigerate as soon as possible after harvest. If possible, remove unmarketable fruit from the field.

Products registered for spotted wing drosophila control on berry crops include Malathion and Delegate. Mako, formerly named Ripcord, is registered on strawberries and raspberries but not blueberries and is labelled for “suppression only” for SWD. See www.ontario.ca/spottedwing for current registrations.

Exirel is fully registered on blueberries and other bushberries for SWD control. Bushberries include haskaps, saskatoons, sea buckthorn, currants and blueberries.

Figure 1: SWD damage on strawberry (photo not from this year!)

Figure 1: SWD damage on strawberry- soft or bruised appearance on on side  (photo not from this year!)

Advertisements
This entry was posted in Berries, Blueberries, Cherries, Currants, Elderberries, Cranberries and more, Insects, Peaches, Pest Management, Raspberries, Strawberries, Tender Fruit and tagged , , , , , , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s