I'm no expert but I'd leave it alone. As long as the bark is intact without there being a break all the way around the trunk, they should be fine

If I'm correct, the shallower cracks are a result of the tree trunk growing thicker. The soft wood should harden off and shouldn't compromise the tree. Keep an eye on them until they do. You don't want insect infestation or any weird growths of mold or fungus or something.

I know the first instinct might be to wrap over the cracks to protect them, don't do that. The wraps tend to hold in moisture and provide a fort for insects.

It sounds like normal tree growth as Bob says.

There's a point in there where the bark starts to shift over from the smooth, 'sapling look' to the rugged, tough bark look, which on an ash tree is just all kinds of vertical splits.

Thank you, both. It's a relief to know we don't have this extra springtime thing to worry about.

Robin,

I'm wondering if the split is on the SW side of the trunk. If it is it could be sunscald. I wrap all my newer deciduous trees with tree wrap for the first 2 or 3 years after planting. I wrap around Thanksgiving and remove around Easter. If it's leafing out it may be a minor thing. I agree there's nothing to be done, just see how it goes.

Barb

Hi, Barb. It is leafing out nicely. Split is on the NW side actually. We did wrap it for two years. Nice to hear from all of ou again. Thanks.