I was clearing weeds from around my Ashmead instead of looking up at the fruit, and saw eruptions at the lowest 1' of the trunk, with what look like red roots starting to emerge. It's disturbing.



Dunno why the picture isn't posting. Here's the link for the first.

And a closeup:



Which is here.

What is it and if it's as bad as it looks, what do I do about it? The tree produced nicely this year for the first time, and I didn't expect to find skin lesions on it.

mh

Those are burr knots. They are an inherited tendency in some apples. Those are aerial roots growing from them and they aren't harmful to the tree. Some old varieties were grown from cuttings because burr knots made them easy to root.

Phew. Thank you.

Is M111 prone to this? I can't tell where the graft union is any more, but since this only goes a foot up, it looks like just the rootstock. Does it want me to give it some nice dirt to live in?

Most Malling rootstocks have some tendency to burr knots because of their ability to be propagated by stooling (layering). In the NW the knots don't need to have anything done to them.