• SWD numbers continue to increase! Pressure from this insect is very high now.
  • Use all forms of management- weekly sprays, regular, thorough harvest (every 2 days or less) and immediate post-harvest cooling to less than 5 C (preferably cooler).
  • SWD is present at almost all of our monitored sites, including Grey County and eastern Ontario to Ottawa.

swd-catches2016f2

  • Use the salt water test to look for SWD in fruit.
  • Pyrethroid insecticides (MAKO) will not work well in hot weather and will cause in increase in mites. Save the use of this product for later – when weather cools off and mite pressure is low.
  • Two spotted spider mite is also a problem in many strawberry and raspberry fields – SWD sprays are hard on predators (especially pyrethroids) so monitor your fields for mites.
  • Blueberry growers – if you can’t spray your whole field, at least consider spraying outside rows
  • Heavy rains will reduce insecticide residue. Re-application is needed after ½-inch rains.
  • If you can’t keep up with harvest in day neutral strawberries consider removing older blocks.
  • If severe infestation occurs, strip ripening fruit from infested blocks of raspberries and day-neutral strawberries, spray and start again.
  • In fall-bearing raspberries, bees and pollinators are abundant right now. Protect pollinators by choosing least toxic options and spraying at night.
  • Hot, humid conditions can lead to spray burn. Make sure temps have cooled off below 25 C before you spray.

Table: Summary of Spotted Wing Drosophila (SWD) Trap Captures

Week traps collected
# sites with SWD/# sites checked
# SWD trapped
Ave # SWD/trap
Counties where SWD was found
Crops where SWD was trapped
May 29 – June 4
0/7
0
0
_
_
June 5 – June 11
2/16
2
1.0
Essex, Niagara
wild hosts
June 12 – June 18
3/24
3
1.0
Kent, Elgin, Niagara
wild hosts, strawberries
June 19 – June 25
3/25
3
1.0
Essex, Middlesex
wild hosts, raspberries
June 26 – July 2
4/30
11
1.6
Essex, Kent, Brant, Elgin
wild hosts, strawberries, raspberries
July 3 – July 9

 

9/29
27
1.8
Essex, Kent, Elgin, Middlesex, Norfolk, Oxford, Waterloo, Niagara
wild hosts, raspberries, peaches, cherries
Jul 10 – Jul 16

 

 

30/30
136
4.7
Essex, Kent, Elgin, Middlesex, Norfolk, Brant, Oxford, Haldimand, Niagara, Durham
Wild hosts, blueberries, blackberries, raspberries, strawberries, peaches, cherries
July 17-23

 

30/30
1,757
31.4
Essex, Kent, Elgin, Middlesex, Norfolk, Brant, Oxford, Haldimand, Niagara, Wellington, Peterborough, Northumberland, Grey  Stormont, Dundas and Glengarry
Wild hosts, blueberries, blackberries, raspberries, strawberries, peaches, cherries, saskatoons, plums, pears
July 24-July 31

 

27/29
4,147
59.2

 

Essex, Kent, Elgin, Middlesex, Norfolk, Brant, Oxford, Haldimand, Niagara, Wellington, Peterborough, Northumberland, Grey , Stormont, Dundas and Glengarry
Wild hosts, blueberries, blackberries, raspberries, strawberries, peaches, cherries, saskatoons, plums, pears
August 1 – 6
29/29
6,800
80
Essex, Kent, Elgin, Middlesex, Norfolk, Brant, Oxford, Haldimand, Niagara, Wellington, Peterborough, Northumberland, Grey , Stormont, Dundas and Glengarry
Wild hosts, blueberries, blackberries, raspberries, strawberries, peaches, cherries, saskatoons, plums, pears
August 7 – 13* (Data incomplete at this time)
17/29
17,346
309.8

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