July 9, 2017
As we move into midsummer, the busy hive of early season pest management is largely behind us, and we just need to keep a few things in mind. On the disease front, sooty blotch and flyspeck have the potential to be a big problem this year, so fungicide coverage should be maintained against those diseases. Use the NEWA model to guide applications, and know that two inches of rain are needed to remove previous spray coverage. These are purely cosmetic diseases (but in bad years the cosmetics are well-beyond consumer acceptance) , so fruit that is definitely destined for cider does not need management for them. Fruit rots may be an issue, especially if some hot weather rolls in. Keep a close eye especially on Honeycrisp, that cultivar may need a specific black rot treatment. I hope scab is under decent management, but where it snuck through, I’m afraid you’re still in the 7-10 day fungicide mode until after terminal shoot buds set. Continue to keep an eye out for fire blight strikes and cut out immediately.
As for insects, apple maggot (AM) is the main one we’re keeping an eye on. If you are planning to use them, red sticky spheres should have been deployed by now to monitor populations and flight to determine the need to treat. One Addison county orchard has already reached treatment threshold, and I expect others to need treatment in the next couple of weeks. But AM isn’t a problem in every orchard, so prophylactic spraying isn’t ideal. Codling moth (CM) has begun its second flight in most orchards, and eggs will be laid and will be hatching in coming weeks, there is no need to manage now. Mites may be a problem in some orchards, I have seen one block which was over threshold for two-spotted spider mites and required treatment already.
All sprays at this time of year, especially on Honeycrisp and Cortland, should include calcium in them, and applications of Ca may actually drive the spray schedule on those cultivars. Otherwise, keep mowing to improve air movement and reduce disease pressure in the orchard, walk those rows regularly (since you aren’t driving them as much with a sprayer), and keep note of the now incidental pests that are thankfully less common but easily missed, compared to those we all know are in our orchards in spring through fruit set.
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