Why did our Japanese Maple die?

Asked June 18, 2019, 10:29 PM EDT

We have had this beautiful tree for 5 years, and it has grown and filled out each year. It now appears to be dead. I'm hoping there is some chance we can still save it. IA couple of people told me they had trees (other varieties) die, as well, and were told it was some kind of insect. My husband thinks he saw buds before we left town in May, but when we returned last week, nothing was growing. Some of the branches still bend without breaking, so it seems that whatever killed the tree didn't do so until this Spring. I see no sign of bugs or fungus, nor of the bark having been eaten by an animal. There is a small hole in the dirt near the trunk (visible in the third photo attached, which makes me wonder if some animal could have dug under the tree.) We have another Japanese Maple in another part of the yard that has no buds or leaves on existing branches, but leaves are growing on the lower part of the trunk

Hennepin County Minnesota

1 Response

The extreme cold that Minnesota experienced in late January has taken a toll on many plants. Evidence of this is widespread and many species have been affected including native plants that are considered reliably hardy here.

Japanese maples are marginally hardy in Minnesota so they are especially susceptible to damage from severe cold. Others in the Twin Cities area have lost Japanese maples this spring.

University of Minnesota plant specialist Emily Hoover explains what may have happened to the maples this way:

"Healthy new growth in spring suddenly shrivels and dies. The tree has enough stored carbohydrates in the wood to get the buds growing in the spring. But the underlying vascular tissue that conducts water has died or been significantly injured. When the first warmish days arrive, and water is needed, the buds or new leaves wilt and die due to a lack of water from the root system."

Cold damage effects vary. Some plants are killed outright. Others decline and die in a year or two and still others recover. The outcome may be apparent later in this growing season or it may take a year or two to find out how the maples will fare.