Knowledgebase
2 issues with Norwegian Maple #873805
Asked June 19, 2024, 3:02 PM EDT
Hello and thank you for your time!
We have a Norwegian Maple in our backyard here in Fort Collins. It was planted 2 summers ago, in 2022. It was maybe 3-5 years old then. It was stressed when we planted it but recovered quickly it seemed and has seemed to do well since then.
But last night I was just out watering some of the rest of our garden when I noticed one main branch of the maple that seems to be withering. There is the main trunk, and then two main branches shooting off from about the same point in the tree. It is one of those two that seems to be in trouble.
From the house side the tree had appeared fine and I hadn’t given it a close inspection for a long while.
Going closer now though, it’s almost as if the bark of the main trunk has a deepish split in it (that's potential issue 1) and then the one side’s leaves are withering (issue 2).
Maybe with the trunk, that's just how deciduous trees grow? (Pics attached.)
Second, on the withering branch, I couldn't see a break in the offshooting branch, such as if something mostly or partly broke it.
Any thoughts? Happy to pay for your expert advice, of course!
Larimer County Colorado
Expert Response
This is a frost crack and it's pretty significant. My suspicion is that it's directly affecting the wilting branches, which are no longer getting resources from the tree's roots or through the cambial tissues.
Maples and other thin-barked trees are very susceptible to frost cracks and sunscald during the winter. These are both temperature ailments. We get freeze and thaw during winter - especially on the south and west side of the trunk. The warm winter days cause the water in the trunks to thaw and start to move. At night, when the temperature drops, the cells freeze and burst (and then you see cracks or bursting bark).
Unfortunately, the tree is unlikely to seal off a wound of this magnitude. It looks like it's fairly deep and essentially split the trunk in half.
You can continue to monitor the tree and see how it does over the next few months - keep up with good cultural practices (regular water) and try to prevent additional stress.
If you do need to replace, wrap thin-barked trees from November to mid-April with the crepe-paper wrap for the first few years the tree is in the ground.
