Question
My maples(I don't know what kind) have white spots and some larger black spots on their leaves. The trunks have greenish spots.

Answer
Hi Mary:
Sounds like your trees have a rainbow of spots on it! Difficult to say for sure w/o seeing how exactly these spots look, but the white spots on the leaves may be a type of insect, especially if they appear somewhat raised on the leaf surface. These may be a type of scale insect. The black spots may may be a type of fungus disease called anthracnose, especially if you have had lots of rainfall earlier. If these tree are larger, chemical management may be impractical or not too feasible.  Just raking up and destroying (burning is a great way if your community allows this practice)the leaves that fall to the ground during the late winter or early spring BEFORE the new leaves on the tree start to form is a good way to minimize many insects and diseases.

The green spots may be an algae or a type of lichens that can appear on the bark, especially if the tree gets lots of shade on the trunks. I doubt if these items can jeopardize major health concerns.

If you wish, you can send me a closeup photo of the spots on the leaves and trunk and I can take a look. Be sure the photo is in focus by reviewing it on your computer before you send.  With this current system, I believe one photo is allowed per question/comment.

Regards
Steve