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Cranberry IPM Message

If it has been more than 1 week since your last fruitworm spray, you should be checking fruit for unhatched viable eggs. Do not exceed 19.5 oz per acre per season for Delegate. If you are sweeping, you may see cranberry weevil and flea beetles. Belay can be used but only if the bees are gone as it is highly toxic. Check for handler restrictions for this and other insecticides!

If you are concerned about sprays going out in unstable weather pattern, Altacor should have good residual and rainfastness. 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.

You may need to be checking early varieties and hybrid varieties soon for %out-of-bloom (%oob). 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. It is too late to be spraying for weevil (unless you have LW Howes).

We have had reports of spag and green spanworm flying in the past week.  Many growers are applying first fungicide (or second fungicides on very early varieties). Try to actually do an “in bloom” count to properly time your first fungicide. If you are applying Select or Select Max, please note that you cannot apply the herbicide between hook and fruit set.

Pheromone traps should be out by now. Place them on the upwind side of the bog so that the scent flows onto your bogs with the prevailing winds. BHF larvae are still being picked up but they should be pupating soon. Spag is also still out but at a size where you can see them.

Scale is showing up more frequently on bogs this spring. 

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.