Walnut bunch disease showed up in my orchard a while back. After searching the internet the only solution is to prune the affected material.
I found an obscure article from Red Fern Farm that stated using Zinc Sulfate to treat it. Had my doubts after all the collegiate articles read, but I bought it and spread a couple pounds around on the ground. So far the results are really promising. This year all diseased material I could not reach to cut is dead and I see no signs of more showing up. We will see as the year progresses.
Although this is not conclusive, I do find it very promising and worth sharing.
When I get a chance will take some pics, but I’m calling this a success. My trees have been fully restored without a trace of Bunch disease. What I need now is to find someone else with the same problem to confirm my results.
Zinc sulphate is used on pecans to supply zinc to the tree. It is an essential micronutrient. Nickel is another that pecans require. Look up Mouse Ear and Rosette for pecans to find relevant information. Why zinc sulphate? It tends to acidify the soil over time which makes zinc more easily absorbed by the tree. Caution that in soils that are already acidic, this may force use of liming agents to increase pH. Given the close relationship between pecans and walnuts, both likely need the added nutrients.
The scientist claim there is no cure for WBD. If that is true my results are astounding. I’m not growing pecan, but have plenty of walnut. Two of my trees were affected and one was almost entirely witches brooms. Now they are back to beautiful again.
As side note the persimmon next to them seems to be growing faster.