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Cranberry IPM Message

The Entomology Lab reports: With the warmer weather coming along, winter moth (WM) larvae have been picked up in sweeps in Cranberry land! A grower reported average counts of 10 with a high of 17 larvae.  Larvae measured at 1/16 of an inch (see photo below).  

Frost Tolerance
Early Blacks, Stevens, and Ben Lear are at 20 degrees frost tolerance; Howes are at 18 as of today.
The window for putting on late water floods has closed unless your bog is in a particularly cool location and the buds are still tight and red.

News on the disease and insect fronts has been quiet. We have seen some flea beetle damage but reports are fewer. Remember that our fungicides work as protectants, not as curatives. That means if you apply a fungicide AFTER you see the rot, it will do no good. In general, applying fungicides this late is of little use.

We are at the end of the window to use Admire or related products for grub control. If your bees are off the bog, you can apply Actara and Admire if needed. Cranberry weevils (second generation) are out and abundant in some cases. The threshold for spraying is higher for the summer generation; an average of 9 is used to trigger a spray.

If your bees are off the bog, you can apply Actara and Admire if needed. Cranberry weevils (second generation) are out and abundant in some case. The threshold for spraying is higher for the summer generation; an average of 9 is used to trigger a spray. Remember Actara is Zone II regulated and highly toxic to bees.

If your bees are off the bog, you can apply Actara and Admire if needed. Cranberry weevils (second generation) are out and abundant in some case. The threshold for spraying is higher for the summer generation; an average of 9 is used to trigger a spray. Remember Actara is Zone II regulated and highly toxic to bees.

Altacor should have good residual and rainfastness, if you are concerned about sprays going out in this unstable weather pattern that we currently find ourselves. Please use the traditional cranberry fruitworm timing for Howes, spraying 7-9 days after 50% out-of-bloom. This is still the best management strategy for this variety.

Things seem fairly quiet so far. State Bog is 60-80% IN bloom. The Stevens at Rocky Pond Bog in Miles Standish are 5% out-of-bloom. At State Bog, the Ben Lears were 25% out-of-bloom and the Early Blacks were 13% out-of-bloom mid-week.

You may need to be checking early varieties and hybrid varieties soon for %out-of-bloom. Bloom is moving quickly in some areas. It is always good to get 2 %oob counts BEFORE you hit 50%, just to improve your estimate. Some growers may be spraying for fruitworm control by the end of next week. Late water Howes are very behind and barely at bloom yet.

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