Sooty Blotch and Flyspeck – Facts for Fancy Fruit

Sooty Blotch and Flyspeck

Flyspeck and Sooty Blotch

Flyspeck and Sooty Blotch

At midseason, scout fruit (20-30 apples or pear) in the interior canopy of sample trees. Signs of this disease are more obvious on light colored fruit, like Golden Delicious, Pristine, or Yellow Transparent. The disease is worse in poorly pruned trees in the wetter, foggy, slow-drying areas of the orchard. This year, in some parts of the state, it might be the entire orchard, we’ve been so soggy lately!

 Signs of this disease would be showing up about now (mid-July), particularly on fruit where protection was lacking or washed off due to consistently heavy rains. Continue to observe 25 fruit in the interior canopy of sample trees. Fungicides containing strobilurins (Compass, Flint) or strobilurins + SDHIs (Pristine, Merivon, LunaSensation) should be applied to fresh fruit showing any infections. Presence of these diseases is a good indicator that fungicide surface residues are lacking or very low, and signals potential need for treatment to control these diseases, other summer rots, and post-harvest rots.

 Next year, be sure to prune trees to improve air circulation. With the Olympics fast approaching, you should be able to kick a soccer ball through the tree. We will leave that proverbial cat to the voles below!

Remove any nearby wild or neglected apple or pear trees. Use this as an excuse to get rid of any flowering (aka ‘Bradford’) pears, too!

Backyard growers, remember: This disease looks a little nasty but rarely affects the quality of the fruit. You can eliminate any signs of the disease by vigorous washing, scrubbing, or peeling the fruit.

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