This post contains a summary of trap counts for Aug 121-29, 2019.  The numbers reported are number of SWD per trap.

The regional monitoring program is being conducted in berry and stone fruit crops and grapes in Essex, Chatham-Kent, Norfolk, Niagara and Durham counties

The monitoring project is supported by a grant from the Canada Adaptation Program and collaboration among Niagara Peninsula Fruit and Vegetable Growers Association, Ontario Tender Fruit Growers, Eastern Ontario Berry Growers, Grape Growers of Ontario, OMAFRA staff and private consultants.

Traps were first deployed in berry and stone fruit blocks and have now progressed into table and wine grapes.  We have placed 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.  Click here for instructions on doing this test.

CountyCropCrop stageNumber of SWD per trap
Aug 7-14Aug 14-21Aug 21-29
EssexField raspberry42F, 38M54F, 28Mretired
Peach89F, 21M62F, 12Mretired
Wild547F, 265M35F, 31Mretired
Plum43F, 18M76F, 17Mretired
KentBlueberryharvest15F, 12M2F, 1M66F, 89M
Strawberryripe4F, 16M1M3F, 7M
Raspberrypost harvest16F, 20M6F, 7M72F, 29M
NorfolkWild raspberry15F, 17M94F, 51Mretired
Blueberry67F, 34M55F, 15Mretired
Blueberry36F, 10M82F, 24Mretired
Blueberry34F, 14M112F, 19Mretired
NiagaraStrawberryripe12F, 5M12F, 8M25F, 14M
Wildn/a58F, 18M10F, 28M2F, 1M
NiagaraWild40F, 23Mretired
Mulberry94F, 309Mretired
Raspberry63F, 62Mretired
Currantharvest49F, 65M25F, 31M61F, 58M
Blackberryripe124F, 67M41F, 8M72F, 60M
Raspberry46F, 83Mretired
NiagaraApricotripe49F, 15M37F, 14M52F, 50M
Plumripe98F, 25M26F, 10M38F, 47M
Nectarineripe17F, 21M6F, 2M26F, 18M
Peachripe25F, 7M39F, 9M10F, 8M
NiagaraPeachripe30F, 84M13F, 31M56F, 53M
Peachripe69F, 217M17F, 46M75F, 30M
NiagaraRaspberry55F, 88Mretired
Raspberry18F, 20Mretired
Niagaranectarine71F, 49Mretired
nectarine16F, 14Mretired
peachturning colour33F, 44M26F, 21M28F, 7M
peachturning colour53F, 32M26F, 24M40F, 34M
Niagaranectarineharvest5F, 4M3F, 6M12F, 28M
peachripe2F, 2M2F, 6M13F, 16M
peach18F, 18M5F, 7Mretired
apricot12F, 32Mretired
table graperipe24F, 17M
wine grapeveraison6F, 7M
Niagarawildn/a18F, 29M
wine grapeveraison4F, 14M
wine grapeveraison25F, 24M
wine grapeveraison14F, 12M
table graperipe40F, 38M
wine grapeveraison18F, 22M
Durhamwild7F, 26M48F, 143 Mretired
Blueberry21F, 13M86F, 52Mretired
Blueberry8F, 3M58F, 64Mretired
Blueberry18F, 10M19F, 12Mretired

Once sustained catch occurs (two weeks in a row with SWD) growers with ripening crops susceptible to SWD in that region should consider using a product with activity against SWD in preharvest sprays.

SWD may have an impact on sour rot development as it can carry the bacteria and yeasts responsible for the disease (as can the everyday run-of-the-mill Drosophila species).  Therefore it is recommended that once fruit is over 12 Brix, any product selected for managing preharvest grape berry moth should also have activity against SWD.  This topic was covered in a previous blog post:

Check the SWD product registrations on our website.

We are currently testing susceptibility of peach varieties to damage by SWD.  Fruit collected at pre-commercial ripeness, commercial ripeness and tree ripe are being exposed to SWD under lab conditions.  Fruit firmness is measured to classify into the 3 ripeness classes.  Fruit are exposed to SWD for 24 hours and then incubated to allow any SWD to mature to adults.  This will be continued into peaches and grapes.  According to David Jones, MSU extension expert, “For plums and peaches, you shouldn’t be starting management the moment that color creeps in,” he said. “If you initiate a spray program around 4 to 5 pounds of firmness, you should be able to catch them.”  Source:  Our preliminary trial on apricot last year supported this observation.


This project was funded in part through the Canadian Agricultural Partnership (the Partnership), a federal-provincial-territorial initiative. The Agricultural Adaptation Council assists in the delivery of the Partnership in Ontario.




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