Yellow card placed in the middle of green raspberry foliage.
Berries Insects

Spotted Wing Drosophila Update – July 2 2026

SWD continue to emerge in some areas of the province. On-farm Monitoring with sticky cards and lures is important for effective management.

This is an update for traps set up between 18 June and 25 June.

Traps for spotted wing drosophila were placed at a few sites in 2026 – Norfolk, Oxford, and Middlesex.

SWD was identified this week in Oxford and Norfolk counties. No SWD was found at the other locations.

Trap collected period of:
County/region where SWD was trapped
# of traps with SWD
Total number of SWD trapped this week
# SWD/positive trap
May 20 – May 27
0
0
0
0
May 27 – June 3
0
0
0
0
June 3 – June 10
0
0
0
0
June 10 – June 17
Norfolk, Middlesex
4
6
1.5
June 18 – June 25
Norfolk, Oxford
3
4
1.33

Management is needed once we have sustained catch (2 weeks in a row) and ripe fruit is present. These are the first catches of the year, however, we have limited trap locations so monitoring on your own farm is important. If there is ripe fruit present (strawberries, early raspberries, haskaps) use salt water tests to monitor the fruit as an early warning. Watch for soft, juicy fruit.

Pairing a yellow sticky card with a commercial lure for on-farm monitoring is important for timing insecticide applications and effective SWD management.

Picture of a yellow sticky card with SWD males.
Figure 1. Picture of a yellow sticky card with SWD males (Photo credit: Hannah Fraser).

Insecticides are needed once SWD is active in your area and there is ripe fruit present. See the table below for a list of registered products. Don’t count on sprays alone:

  • Tighten picking schedules- regular, thorough harvest (every 2 days if possible) is important.
  • Cool fruit immediately after harvest.
  • Keep alleys clean- either remove unmarketable fruit or crush it in the alley
  • After unmarketable fruit is removed it should be destroyed (disposed of, or leave in plastic bags in the sun).
  • Make the environment less favourable to SWD- prune the canopy and manage water to reduce humidity (repair leaking drop lines).
  • Calibrate your sprayers now to ensure excellent coverage once you start to spray.
  • Insecticides target SWD adults- make sure to spray when adults are active, in the morning (6am-10am) and evening (6pm-10pm).
  • Do not spray in temperatures over 25°C.
  • Renovate June-bearing strawberries as soon as harvest is over.

2 comments on “Spotted Wing Drosophila Update – July 2 2026

  1. Pam Fisher

    hi – what do you mean by the column heading ” Total number of SWD trapped this week”
    I asssume it is flies, but then…the next column woudl suggest its not!

    • Jason Lemay

      Hi Pam, it is the cumulative number of flies (SWD) across all locations. The next column is the number of flies per sticky card, only counting the cards that had SWD captures. Does this make sense?

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