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Healthy Fruit 1999 Vol. 7:4

May 7

SPECIAL ALERT

Scab Alert from Dan Cooley

It seemed to me that I should take advantage of the electronic technology we have, and support what you probably are already thinking. Hence this special Friday alert.

I just reviewed the weather forcasts via SkyBit and the NWS, and it looks like some sort of rain for Saturday through Tuesday. There is some difference between the various sources, in that one says alot of drizzle, with solid wetting periods over the 4 days, while the other says showers and doesn't estimate wetting. This is somewhat like last year's pattern of a 10 day soaker, which SkyBit actually predicted reasonably well. It will take alot to be like last year, but this still looks to be a difficult rainy period. Add to this a heavy load of mature ascospores, plenty of new green leaves, and I am betting we have the heaviest risk of scab we will see this season.

My advice, simply put, is spray. In all liklihood, prolonged rain will remove any protection by Tuesday, and you will need to be ready to move in again. The previous rain probably removed fungicide protection by yesterday (Thursday), and I would be reapplying now. Maintain protection if at all possible, and if you think that the protection may have broken, plan to use a post-infection program. Now is the time to spend your scab fungicide dollars for the year.