Ask a Consulting Arborist Q&A: Leaf, Seed, and Flower Concerns

Q: Pear tree is losing leaves in the summer and mushrooms grow nearby. What's wrong?

Wednesday, December 30, 2015  

Q: We live in Southern California and are concerned about a pear tree in our backyard that was planted 25 years ago. It is 25 feet tall and 20 feet wide, offering some privacy from neighbors. Our concern is that it is not as full as last year and is losing leaves like it is fall rather than summer. Mushrooms come and go weekly in the dirt surrounding the trunk of the tree.

A: Pear trees are subject to a good number of diseases. Long distance diagnosis is not reliable or even worth the trouble. Some diseases are so common to pears, you may find arborists that will give you a reasonable guess. It would be better to take some fresh mushrooms and freshly fallen leaves to a county extension office. But the best thing would be to have a plant pathologist come to your home to diagnose the condition. He or she may need to check roots or look under the bark, which is best done on site, and may find several diseases infecting the tree. Based on your message, it sounds like there are probably two diseases. Some Registered Consulting Arborists are more versed in tree diseases and diagnosis than others. If you can't find a county extension agent or plant pathologist to come out, use our website ( to find a local consultant who can help.

Responder: Greg Applegate, RCA #365, Tustin, CA