This afternoon I noticed this growth growing on my dapple dandy Pluot on Myro c29 rootstock. Would this be root knot? And is there anything I can or should do?
Thanks Tim
That looks like crown gall. If so there’s nothing you can do that I’m aware of.
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Is Crown Gall related to Black Knot?The growth looks similar. Brady
Not that I know of. Crown gall can attack both roots and stems but is usually like that pictured or below ground.
Will this kill the tree?
It’s not the best on it. I get my share of crown gall here and haven’t noticed much affect from it, except on young trees transplanted, where it can kill the tree. That said, I’ve not had any trees with crown gall as bad as the one pictured. The galls constrict the tree.
Don’t try to cut the galls out (I’ve done that before). The galls come back even faster.
There is no relationship between black knot and crown gall. Black knot is caused by a fungus, whereas crown gall is caused by a bacteria.
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Not anytime soon. It’s not good but my trees lasted with severe infection for 5-8 yrs. Then I removed them for other reasons. Citation is particularly susceptible.
Since there is no cure, the tree should be removed, because it
can spread to other trees and plants.
Removing the tree probably isn’t going to help. For every infection you can see there are probably 100 below ground, or will be down the road. Unless you have a resistant rootstock it’s just going to show up on the next tree. I wasn’t able to find trees on any rootstock that’s really resistant.
Just live with it and recognize that it will get worse if you ever have to replant new trees in that area. Cut off that gall if you like and can without damaging the tree too much.
I’ve lived with severe crown gall about 11 yrs. It didn’t kill any of the original trees on Citation but when dug out at varying ages they were massively infected. Trees replanted in the same area about 3 yrs ago on Citation didn’t do well at all, some died. I won’t plant on that stock again. And I’m not sure there is a rootstock that would stand up to it now.
If an established tree can live with it but a new tree dies, I’m not sure replanting helps much. But our soil is naturally infected. If ones soil were clean and the disease were introduced on a nursery tree then removing the tree might help.
Thanks everyone , for all the input! I have about 40 trees in this area so I can expect to see more of this in the future 
Personally I would remove the tree AND the soil, because the soil is also contaminated. If you don’t remove the soil, anything that you plant in the same spot, will also become contaminated. Just replace the soil from another area, and you should be able to replant in the same spot, will no ill effects.
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If it is caused by a bacteria (or fungus for that matter) then it is everywhere in the yard that your feet have trod, or animals have trod, etc. Keep the trees healthy and their susceptibility decreases.
FWIW I have a pecan that has had a gall like that for over 30 years. It involves less than 1/5 of the circumference of the tree.
It probably has dozens if not hundreds of galls below ground. Around here, in a desert I might add, the native cottonwoods are heavily infected and reach up to 5ft trunk diameter. Pecans are also infected based on what I’ve seen.
There’s a product called Gallex which actually kills/removes the galls, but you have to treat each gall individually. I’ve never used it though.
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I’m looking for a place that sells the Gallex, but haven’t located one yet. I’d like to give it a try.
Sweetdill,
My guess just about any chem supplier who specializes in fruit/vegetable could probably order it. Some chem suppliers will ship chemicals direct via Ups as long as it doesn’t require hazmat shipping. If it requires hazmat, you may be out of luck. I’ve gotten some hazmat items shipped, but it has to be done by motor freight, which would be very expensive for just a small quantity of material.
Some of the chem suppliers I have used are Midwest Grower Supply (Stanberry MO), Deerfield Supplies (Elgin KY), Crop Production Services (i.e. CPS). CPS has offices/warehouses all over the U.S. but their main office is in CO. You can call their main office and they can tell you if any of their warehouses stock the item you are looking for. You should be able to Google all these numbers.
Alternatively, you might try calling AgBioChem and tell them you want to buy their product and would like to know the name of a dealer/distributor who carries it.
Thanks so much Olpea. Will do!