THE Hawthorn tree is a robust and long-lived genus (Crataegus). Part of the rose family, they light up our countryside boundaries with spectacular blossom and later provide food for our wildlife.

Q: We recently moved into a house with a hawthorn tree in the front yard. The tree had beautiful red blooms in spring, but now it has developed unsightly black spots on the leaves. Is there a way to ...

Lance is a caretaker of a nature preserve in North Carolina and an expert on hawthorn trees. (The species Crataegus lancei is named after him.) And for years now, he’s been chronicling their ...