North American Fruit Explorers mailing list at ibiblio

[Don Yellman <don.yellman@webformation.com>]

Dennis:

I have had both bacterial spot (which also visibly affects the leaves) and 
peach scab in past years, and managed to eliminate them with timely dormant 
sprays of Kocide.  Neither of these diseases resulted in blobs of pectin on 
the fruit, and the photo in your referenced link, which looks exactly like 
what I had,  shows none.

You may not have serious oriental fruit moth infestations in northern 
Illinois, but in the east and southeast we do.  While we have yet to hear 
from Shirley with perhaps a better description of the problem on her little 
peach fruits, and a more specific location than zone 7, she does live in the 
southeast somewhere, and that is where the OFM is most active.  In many 
southeastern orchards, the OFM will visit every peach on the tree if allowed 
to do so, leaving from 1 to 3 little blobs of pectin on the surface.  Such 
fruits will soon contain OFM larvae, which tunnel around near the pit and 
usually cause the fruit to drop prematurely.  Even OFM penetrations that do 
not result in larvae compromise the integrity of the skin, which causes brown 
rot later in the season.  When I spray for OFM early in the season, I also 
include a fungicide like Captan in the mix to prevent other early problems of 
peaches: small patches of powdery mildew and rusty spot.  When either of 
these is visib
le on a peach at thinning time, that is one to take off.

The oriental fruit moth can also affect the twigs of trees when the larvae 
tunnel in, leaving swollen ends on small branches, and causing twig and even 
branch dieback.

The only things the OFM likes better than peaches are smooth-skinned stone 
fruits such as nectarines or pluots.  To grow such fruits in the southeast, 
you pretty much have to stand by the tree with a sprayer all season long, or 
bag the fruits after thinning.

Don Yellman, Great Falls, VA