Honeycrisp apple tree diseases

Asked December 31, 2020, 1:52 PM EST

Hi, My name is Mike and I have 2 honeycrisp apple trees that are more than 6 years old that look fine in the spring and do blossom but by mid summer the leaves have curled and browned and the resulting fruit doesn't amount to anything. Should I remove the trees ? I do spray them when I start to see this with fungicide but to no avail. If I remove them will they infect other trees? Thank you for your advice.

Dane County Wisconsin

1 Response

There could be several causes for your Honeycrisp problems, fungal and insects. Sorting this out and identifying the culprits is the first step

Although Honeycrisp is somewhat more resistant than many other apple varieties to the very common fungal disease apple scab, unsprayed trees will still get leaf and fruit spots.

I am putting a link to a web page here that shows common disease and insect problems of apples so that you can identify your problem and learn typical spray strategies.

https://williamshane.weebly.com/uploads/2/7/0/7/27077603/apple_spray_for_backyard_gardeners.pdf

Honeycrisp is prone to a leaf disorder that is physiological / nutritional in nature.

Here's a link to pictures and descriptions so that you can judge whether this is part of your problem. General control strategies are also mentioned.

https://www.canr.msu.edu/news/honeycrisp_leaf_yellowing_showing_up_on_michigan_apples

To judge if it is an insect causing the problem, look for signs of burrowing / chewing in the fruit or on the leaves.