Red Maple are one of the most diseased trees. The are very beautiful shade trees and are often used in residential applications. They are very close relatives of the sugar maple so they have similar diseases. Red maples leaves are not always red like there name assumes. The backing of the leaves if often red and there fall color is a beautiful deep red color. If you were looking at a sugar maple and a red maple side by side in a distance you would notice that the red maple is a darker shade of green. While the sugar maples color more resembles a kelly green or a lighter shade of green. They look very nice when they are planted and take quite some care to start growing. Often when trees get mature homeowners leave there trees alone and they become diseased and it often leads to the death of the tree.
Red maples are a tree that you must look out for its health at all times. Most mature red and sugar maples that you see are not very healthy looking. they usually have large cracks up and down the trunk where insects or a rotting fungus once was. This kind of tree should be looked over with a fine tooth comb because its list of diseases is so extensive that I could not write about them all for the sake of over information. I did include a link to a website that has all the information on red maples as I will do with the sugar maple page. This page will give you any possible information you can possibly ask for when it comes to red maples.
So I will start by saying that there are four different funguses that rot the trunk of the red maple and cause structural problems. The disease that I often treat for is called verticillium wilt. Verticillium wilt is easy to notice for a professional but here is the best way to know that your tree has this disease. If you stand under your tree and look up into the canopy and look at the limbs. If you notice white fungus or basically white spots on the limbs the tree has initial signs of this disease. Once a tree gets verticillium it does not have long to live. Over the case of a couple months a tree with verticillium can go from completely healthy to dead.
There are several different types of leaf diseases. The most fatal is called acerinum. A picture of what this disease looks like is the second from the top on the right hand side of the page. Other diseases like tar spot and mildew are cosmetic and rarely affect a trees health.
There are many different types of insects that feed off of the red maple tree. In fact 76% of all of the red maple trees that die come from insect damage. Some of the major varieties of insects that kill the red maple are pictured to the right.
There are two known scales that affect the red maple as well. They are rust colored and white colored. They are both dangerous to the trees health if they are allowed to multiply too much. They often are found around the veins on the leaves.
Here are some thing to look for in your red maple.
White spotting on the branches and or on the trunk
Holes in the bark
Insects are present
Large gash in the trunk (larvae can be present)
Die back on the crown of the tree
Leaves Turning yellow or orange in spring or fall
Noticeable rotting or visible sapstreak when pruning limbs