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[Don Yellman <dyellman@earthlink.net>]

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• From: Don Yellman <dyellman@earthlink.net>
• To: nafex.@lists.ibiblio.org
• Subject: Apple Diseases
• Date: Sat, 18 May 2002 21:17:52 -0400

Jack:

You are not alone. Perhaps due to the highly abnormal weather, I am seeing fireblight scattered all over on mature apple trees that never showed any signs of it before. Must have something to do with that very warm period we had in April, which I thought was great for pollination (and it was), but brought other things as well. I would be willing to bet fireblight is what you are seeing, and, since I am not set up to administer antibiotics, the only thing I can think of to do is snip it off as soon as it appears. Sometime it is just a single, isolated fruiting spur, but more frequently tips of small branches. And I am not even using the bleach-dip method with the pruning shears, which would be nearly impossible as I move around the trees on my ladder. I am doing this as I thin the apples, and I try to cut the infected branches off well below the evident infection. I have made hundreds, perhaps thousands of cuts on this stuff. My only hope is that weather conditions will change enough to stop it naturally. If not, many of my trees are in trouble.

And fireblight is not the only thing I am seeing. Also touches of cedar apple rust on the fruit of many varieties. Often, however, the CAR is visible only on one or two fruits in a cluster, and those are the first to come off. I thought I had done with CAR when I cut down the neighbor's cedar, but there are apparently others in spitting distance and the infection was brought in with the wind and rain. No serious damage visible on the leaves.

But here's the strange part: no apple scab. None. Whatever conditions were favorable to development of these diseases were not so kind to the scab fungus.

Plenty of insect pressures, and very poor conditions for a regular spray schedule. Extremely windy, even in the late afternoons, and rain just when you don't want it. In addition to minor damage from plum curculio, I am seeing quite a bit of injury from what I believe to be the tarnished plant bug, and a lot of what is apparently codling moth on very young apples. I didn't ever expect to see that so early. Entry wound is round, with orange frass left on the surface. I am not even completely certain it is codling moth. I think I am running a laboratory for insects and diseases in my orchard so far this spring, but fortunately, the fruit set was so heavy that I am able to thin off all the damaged fruit and still leave plenty.

This year I have actually caught plum curculio in the very act of penetrating my apples and peaches --- in the daytime! What baldfaced arrogance. I pushed their little snouts down into the fruit and gave them what they wanted.

Rgds, Don Yellman, Great Falls, VA

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