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Plant Diseases/Sugar Maple Tree


Sugar Maple
Sugar Maple  

Sugar Maple up close
Sugar Maple up close  
I live in a suburb of Minneapolis MN. I have a sickly looking sugar maple tree and I don't know what is wrong with it. I planted it in the spring of 2012. By fall of 2013 I started to notice a few white spots on the bark (canker?). Before the tree had leaves on it this spring I could see that the white spots were more severe than I realized.  The white spots start mostly  mid trunk and extend upward into the core of the tree and moves outward from the branches.  Currently the tree is half full of fairly healthy looking leaves (were reddish when they first bloomed and now mostly green). Some of the branches have hardly any leaves and some are half full. The leaves budded later than our other two maples we have (neither are sugar maples). If you scratch the bark it it appears healthy underneath and It has new shoots growing from it.
Last summer was hotter than normal, winter much colder and snowier, and spring and summer have produced record rains. Our yard is sand based but we used quite a bit of black dirt when we put in our yard 10 years ago. It is planted on a slightly sloped area and there is a rain water run off grate approximately 15 feet away down hill. When it rains the area does not seem to get excessively moist.
Can you help me figure out my tree?

The white spots are lichens and are not a problem to the health of the tree. From the information you gave I am not sure what the problem could be. First thin I usually ask if any herbicide was used near the tree. A common grass herbicide is Weed and Feed. This is good for grass but very bad for tree. the problem is the granular herbicide in with the fertilizer will kill the roots. IF this has not been used then the next thing would be the planting method. Normally a hole is dug twice the size of the root ball and as deep. And filled with top soil or potting soil. In some soils the soil itself restricts the roots form growing out ward and causes dieback. I would suggest that the tree be fertilized with 10-10-10 fertilizer at the rate of 1 lb. per inch of trunk diameter scattered around the tree and watered it in good. Apply the fertilizer just before a rain event and you will not need to water. This will increase the root health and in turn the foliage and tree health.  

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Jim Hyland


30 years experiance in the ID and management of forest diseases and ID of landscape tree diseases.

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