Japanese Maple tree’s leaves curl
Our Japanese Maple tree's leaves curl and discolor about mid season. How do we protect it?
I suspect that it is caused by leaf scorch. Here is an article about leaf scorch in japanese maples which will give you guidelines on how to prevent it:
Article with advice: https://www.rhs.org.uk/advice/profile?pid=591
Anthracnose can also cause discoloration and leaf curl:
Photos & Information: https://urbanext.illinois.edu/hortanswers/detailProblem.cfm?PathogenID=5
Insects such as aphids and thrips can also cause leaf curl as well: