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Hello fruit growers,

/SWD is now being reported in nearby states./ Populations in Vermont can 
be expected to increase in the near future, with high numbers typically 
during the end of July into early-mid September, depending on your 
location and local weather.

Here are some reminders about SWD management practices. Using multiple 
approaches is important to success.

*Harvest fruit very frequently* and completely to prevent the buildup of 
ripe and over-ripe fruit.

*Remove unmarketable fruit from the field *and destroy it (bury, send to 
landfill, cook in clear plastic bags in the sun, etc.) to kill larvae 
and prevent them from emerging as adults in your fields.

*Refrigerate fruit after harvest*. Chill berries promptly after harvest 
to 32-33 degrees to slow or stop development of larvae and eggs. 
Encourage U-Pick customers to do the same to improve fruit quality at home.

*Open the canopy,*  pruning to increase sunlight and reduce humidity. 
This  makes plants less attractive to SWD, and will improve spray 
coverage.  Dry, open conditions reduce the number of eggs that will be 
laid in fruit.

*Manage irrigation* to reduce humidity. Repair leaky drip lines, avoid 
overhead irrigation to allow the soil or mulch surface to dry.

*Monitor for the arrival of SWD*. Homemade or commercial traps 
<https://extension.unh.edu/resource/monitoring-spotted-wing-drosophila-swd-traps> 
(from Scentry or Trécé) can be used to alert you to the arrival of SWD, 
and weekly trapping can help understand what's going on with the 
population on your farm.

*Apply insecticides*. Kill SWD adults to reduce egg laying, once 
susceptible fruits have started ripen (and traps or reports indicate SWD 
is present). Add 2 lbs sugar/100 gal to increase SWD interaction with 
pesticides. Add spreader sticker such as 4-16 oz. Nu Film P/100 gal to 
improve efficacy. Follow label instructions, aligning pre-harvest 
intervals and your picking schedule. Rotate insecticides by modes of 
action. Here are lists of labeled materials, conventional and organic, 
compiled Cornell Extension 
<http://www.hort.cornell.edu/fruit/pdfs/swd/berry-insecticides.pdf> and 
UConn Extension 
<http://ipm.uconn.edu/documents/raw2/1840/2021%20SWD%20Insecticides%20for%20Small%20Fruit.pdf>.

*Monitor the level of fruit infestation* using a salt water flotation 
test 
<https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/1/8311/files/2017/04/SWD-salttesthandout-updated-pnd335.pdf>, 
so you know if your management is working, what to communicate to your 
customers, and even whether to sell fruit.

*Additional information:*

Cornell SWD site <https://fruit.cornell.edu/spottedwing/>

Michigan State Univ. SWD site 
<https://www.canr.msu.edu/ipm/Invasive_species/spotted_wing_drosophila/index>

UMass SWD site 
<https://ag.umass.edu/fruit/resources/spotted-wing-drosophila>

Good luck! Vern