Spots on Fruit Trees

Asked October 6, 2019, 1:05 AM EDT

Hello: I have a miniature backyard orchard and I am suffering from spots on several of the leaves on my fruit trees. Would it be possible for you to check out these photos and then let me know: 1. What causes them? 2. How can this tree be healed? 3. When's the best time to apply the treatment, whatever that may be? Unrelated to the spots, could you also provide me with information about proper pruning practices? Specifically: How to prune, and when to prune? I have apple, pear, peach, almond, and cherry trees. Sadly, the plum trees died. Thank you very much, Jeffrey A.

Oakland County Michigan

2 Responses

This is a fungal disease called rust. There are several that infect pears.

If you are not detecting somewhat similar symptoms on the fruit, then it is probably either Japanese rust or hawthorn rust. If you have juniper or hawthorn nearby (within about 100 feet) examine them for galls or swelling on the branches. With hawthorn rust the small fruit may be distorted from infection. These other plants are the alternate host for the disease. If you find the alternate host, you could remove it to help to keep the disease from your pears. Pear leaf infections usually occur from April to early June. Most homeowners do not want to spend the time and money for the 3-4 sprays needed over this period of time to protect their pear leaves.

Regarding pruning of fruit trees...this is a big topic.

See the following to get you started.

https://extension.psu.edu/pruning-apples-and-pears-in-home-fruit-plantings

Thanks very much for this information! The fruit (pears), thankfully, did not suffer from similar symptoms as the leaves and as far as I can tell (taste, appearance, smell) it was fully healthy.

I will check out the fruit tree pruning guide, thank you also for providing that link.