Maple tree, dead branches.
Hello, My maple tree is having a hard time! Last season it had one dead branch and this spring it appears at least 25% is dead. Any ideas what is going on? 1.jpg is a current photo. The other two photos are from last season and one of those is somewhat close up and shows the bark. What are the white splotches?
Depending upon the site, combinations of poor soil aeration, poor soil drainage, deicing salt damage, high temperatures at the site, drought, excavation damage, soil compaction, paving close to trees, stem girdling roots, branch cankers, verticillium wilt, and armillaria root rot cause the tree to decline.
A certified arborist should inspect the tree. The dead branches should be removed.
The white splotches are called lichens. Lichens are a symbiotic combination of a fungus with an algae or bacterium. Lichens are commonly found on the bark of tree and shrubs in Minnesota. In some cases trunks and branches may be completely covered by lichens. This colorful coating however does no harm to the plants. http://www.extension.umn.edu/garden/diagnose/plant/deciduous/maple/branchespatches.html