Knowledgebase
japanese maple disease? #845922
Asked August 16, 2023, 12:45 PM EDT
I have a Japanese Maple that is not thriving. The leaves come out but then proceed to get dry spots that spread throughout the leaves until they're all dried up. The first picture below is what it currently looks like, and the second (redder) was what it was doing last fall. It is still quite small, only 2-3 feet tall. I received it as a gift last summer and planted it then. I was told it is Tamukeyama variety. Any help appreciated!
Albemarle County Virginia
Expert Response
Hello Steve,
Did you plant the tree in full sun?
These maples have a tendency to get sun scald the first year or two. Applying a shade screen will help. Additionally, the leaves appear to have either some fungal leaf spots or were eaten by Japanese beetles or other chewing insects. Fungicides can be applies as soon as you identify fungal spots. Make sure the fungicide you get is labeled for ornamental application. I use either a copper based product or chlorothalonil (Daconil).
Don't be overly concerned. The leaves will drop this fall and a new flush will be back in the spring. If you are seeing more than 50% leaf surface area gone, you can prune or hand pick those leave out.
Keep an eye out for insects specifically bag worms. The eggs are laid by a moth and the worms can totally defoliate the tree within a couple of days, depending how large the tree is. Here is a link https://content.ces.ncsu.edu/bagworms Chemicals are not very effective against bagworms but control is easy by hand picking the insect and dropping it into a bucket of soapy water.
