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Cranberry IPM Message

All LW floods should be off your bogs by now (or if on the Cape, by the end of the month).  Frost tolerance is 29.5 F once the flood is removed, no matter the appearance of the buds.  Sweep for early season insects and CB weevil. Generally, no fertilizer is needed on LW bogs until bloom.

To hear audio recording, call 508-258-9191.

No change from last week regarding sweep catches.  Good sweeping weather is still not here.  Very few small spanworms and a few weevils reported.  Bogs do seem wet but the the talk is that we are in early drought for the area.  Marty has gotten calls about dead spots; diagnosing is on-going.

To hear audio recording, call 508-258-9191.

No good sweeping days except this past Thursday (end of next week looks good too!).  Many growers got out and found generally clean bogs.  Just a few weevil here and there; few flies and spiders.  Just a few very small green spanworm here and there. No treatable populations anywhere reported.  Picture has 3 tiny green spanworm circled.

Some bogs went under water due to the rain on Wednesday night into Thursday. This is a bad time to have fruit under water. Applying a fungicide at this time will not help reduce fruit rot but could give you peace of mind. Growers should do all they can to get the water off as soon as possible (including from low spots of the bog). That would be the most critical action to take at this time.

Flea beetle continue to be a nuisance feeding on overgrowth on the bog. Unless you sweep and get 25 or more on average per sweep set, it does not warrant using a Diazinon at this point.

Sparganothis fruitworm is starting to show up in berries, only about 1/4". If Altacor applications did not get on or if spots were missed, cranberry fruitworm red berries are clear now. Flea beetle are out now feeding on lush growth. Upright dieback has started to appear on some bogs.

If growers missed the timing on their Altacor, red berries are starting to show up.  Chasing these with very expensive Delegate is likely a bad idea as it will only hit a few of the larvae in the berries.  However, timing now with Delegate or Intrepid is rather good if you had high Sparganothis moth flight and want to hit those hatching eggs and young larvae.

Most growers are finishing up fruitworm and fungicide spraying. Altacor for fruitworm is a good choice and you should allow at least 7 days between applications, 10-14 is better. It does have a good residual but don’t take chances and possibly miss your application window. Do not exceed 9 oz/A per season.