After the long winter and wet spring that we have been getting, my huge Japanese maple has leaves coming up. However part of the trunk of the tree has develop white spots. There are also no leaves on certain branches …. Is this something I should worry…do i need to do anything? Please advise.
Thank you for contacting Master Gardeners and sending a photo of your Japanese Maple. It is difficult to determine if there is a serious problem with your Japanese Maple or not–if there is an injury to the bark or if the whitish patches could possibly be lichens and no harm to the tree. You can check What Causes those White Splotches on Tree Bark? . This is an excellent article.
Damage from freezing appears as shrivelling or browning of foliage, and can also include branch die back. To find out whether your bare branches are viable, gently scrape the bark of these bare branches with your fingernail, starting at the tip and working back towards the base of the tree: you are hoping to find green, healthy wood below the bark. If you do find any green wood, prune the tree back to that point.
You may also want to check with an arborist to look into the state of the branches that have no leaves and the state of the bark. To find a certified professional arborist to help you with a tree problem, visit the Ontario branch of the International Society of Arboriculture here. It may be possible that the bark has a fungus of some sort such as powdery mildew, after the wet spring and may need a fungicide which can be purchased at Garden Centres .
I wish you the best of luck with your Japanese Maple.