By 4/1/2018 I had 28 apples on M111, 5 on M7, 4 on Geneva, 2 on M27
So far this year I’ve had 5 m111’s die to Cotton Root Rot. 6-8 Jujubees were affected too; they survived, but fruit tasted awful. Blackberries all died
Cotton Root Rot hasn’t yet affected pears, poms, persimmon, ornamentals, figs
CRR supposedly spreads by root tip to tip.
Should I take out all the apple trees to save the other fruits? or switch to geneva rootstocks?
Geneva’s haven’t been tested for cotton root rot, as far as I’ve heard. I might be wrong. It sure went through your trees quickly. Are you sure it’s cotton root rot?
Thanks. Pretty sure its CRR. When the 1st tree died, a Fuji, I posted & asked for opinions; dug up roots, took pictures, etc. I think we ruled out the other suspects.
Wasn’t borers for any of these trees. Tree’s completely die 7-10 days, typical of CRR. Iron Chlorosis appearance is often the 1st symptom of CRR, several trees had that. Dead Leaves all stay on the tree, another CRR sign. I use a moisture meter; wet, but not waterlogged (which would almost be impossible to do in Dallas). Its easy to push the tree over when its dead, another CRR sign; these have been in ground from 2-6 years.
Another symptom of CRR is cinnamon colored roots which are spongy.This root is kind of spongy. I’m not exactly sure what the root should look like, but it could pass for cinnamon colored, below.
In the second picture, the far tree died 3 weeks ago; the near tree died this week; they’re about 12’ apart.
What a nightmare.
I’ve read about CRR but only since I’ve been on this forum. We are not far from you. I read up on the area it affected and it’s east to the Neches River. Our county’s eastern border is the Neches River. That’s about 20 miles east of us. I would just as soon you kept it over there but man that is tragic! I would be shedding tears!
Katy
So I’ve had some geneva trees die from cotton root rot. 
But I’ve got two anti-cotton root rot leads
-Use “Rhyme” fungicide to protect trees from cotton root rot. The active ingredient is flutrifol. Topguard Terra apparently was effective in protecting grapevines and “Rhyme” has the same active ingredient. Problem is, it’s not labeled for this, so I’m not sure if I spray the fungicide for leaf diseases if it will be strong enough to protect the trees from cotton root rot as well. And I have no idea how to convert fluid ounces per acre to fluid ounces per gallon. Also, it wasn’t 100% success with the grapes. There was still crop loss. And they were applying it by drench.
-I was talking with one an TAMU fruit specialist, and he was wondering why no one ever just tried growing apples from seed and doing rootstock tests for resistance to cotton root rot that way. I realize this sounds incredibly naive, but I was thinking a cheaper option would be to just grow a bunch of random apple trees from seed, plant them in the cotton root rot hot spots and see if one takes. On this line, I’d love to get seeds from “Hashabi” crabapple. Aklaine soil tolerance, heck yes tell me more!
Any thoughts? I’ve heard of using actinovate and increasing organic matter, but has that actually worked for anyone on apple trees?
Spraying a fungicide on the leaves isn’t going to protect from CRR. Even if the fungicide were systemic that’s tall order. They were using a drench for a reason. It would take a lot of volume to soak the whole root zone. And it would likely be a temporary fix.
Yeah, I was thinking that too.
