ID Strange Growth on Apple

Any idea what this is? Think I’ve seen it before on other trees and ignored it but this tree also has some blight going on.



I’m going with burr knots.


Fabulous- thanks. No surgery on that spot.

Lots of blight cankers showing up this winter.

I have had this happen on the trunks of trees that I left the spiral wrap on. It is in several places in a spiral around the trunk. Why would that occur?

It’s not because of what you do. It’s mainly because of what rootstock your tree is on.

Kuffle Creek Nursery says to plant M111 deeper than normal to minimize burr knots (but still keep graft union 2 inches above the soil).

Do you think the rootstock influences the formation of burr knots on the grafted variety on top of it? Or do you think that certain rootstocks are more prone to develop burr knots on their own portion of the stem? Could the tendency to develop these be inherent to each variety - independently of the rootstock it is on, or is it that varieties can develop more burr knots on different rootstocks?

Look like trunk wraps provide shade which encourage burr knot on rootstocks proned to have it.

Here’s the answer for you.


Thanks!! Now it makes sense. The only apples that have burrs in my small orchard are the ones with the spiral wraps. Not only that, but the burrs follow the spiral in the same direction. I have removed them now. They are ugly as all get out. I might add some solid neem to the scars. It may not help but it makes me feel like I’m doing something. Thanks for solving the mystery!

What about the last part? Should I try to smooth them out or remove them best I can?

The article above stated that you can use a knife to cut those root initials out or file them.

I will put that on my list of to-dos. Thanks again for the information!

1 Like

Thank you mamuang! That article has all the answers I need!

1 Like