agree Alan.
my guess is you are more likely to get resistance if you dump them all togetherā¦why not knock the fungus out with one product and wait a bit for it to act fullyā¦maybe to the point the application is just about to lose its potencyā¦and then finish the fungus off with anotherā¦Iāve committed to using only organic (copper and sulphur).and if I have to go another route Iāll decline to grow that variety.
lack of eastern exposure meaning it dries out later in the morning ?
Yes. In my region dew tends to be heavy and the added hours of wetness created by eastern shade seems to compound all fungus problems. Because I manage so many sites I get lots of anecdotal comparison between western and eastern shade.
Eastern shade also encourages cracking in plums, nectarines and cherries and the brown rot that follows the cracking. There is more brown rot pressure in this shade with or without cracks.
If you are stuck with a site shaded from the east you can partially compensate by pruning the trees to an especially open state and keep them that way with several rounds of summer pruning along with the judicious selection of varieties less prone to these problems.
All that said, sometimes sites with especially high black knot pressure have excellent eastern exposure and no obvious explanation for he issue.
Incidentally, I reread the link from Cornell I posted, and it is really just an anecdotal observation by the writer as far as the pile of removed galls near the trees escalating pressure- a logical leap. In a home orchard near woodlands there is always plenty of innoculum blowing around. Itās possible that not much benefit is achieved by removing the cut galls from the orchard carefully. Iāve not noticed a great reduction in pressure when Iāve done so over just letting pieces stay on the ground- but I usually am careful to remove them anyway.
I have a plum, might be Bruce, that gets black knot. I had it all cut out and was free all summer. Early this fall I cut all the branches off and left them laying in a leaf pile. Late this fall when cleaning up I found galls all over them. The moist leaves made the perfect conditions and even though the branches had been cut they were still alive. Morale of the story: Burn or get rid of all the wood of susceptible varieties. Those galls will keep on growing.
Of course galls contain living tissue. Where I live there are usually nearby trees in the woods with galls- native cherries are common here and when understory they more often than not have lots of galls. What you do with what you remove from your own trees may not necessarily make much difference. Commonly Cornell calls for eliminating native cherry trees in the vicinity to reduce disease pressure, but this is often not possible in home orchard situations.
Alan,
I canāt argue with what you are saying. In my case I donāt know of any wild plum or cherry. My issue is wild cedar trees. I get cedar apple rust and quince rust. I am surrounded by them.
The miracle of myclobutanil.
I tried my best to cut it out last year. But I am sure I missed infection. I assume I should start cutting now and paint the wounds with kocide and Chlorothalonil or should I switch to myclobutanil?
This is the only spot i found expressing gum
You might try blowtorching that, I can see new knots at the edges in spots. Either that or cut back further in as there is more coming back there than should.
Donāt look for gum, look for knots on the edges of the cuts.
Unless the variety is special I would cut the tree below the graft and start over with a different variety. I used to have a methley with black knot. It had great fruit but was a carrier and would infect my other plums. Once I got rid of it my other plums are free of it.
Should you cut it you will have strong roots that will make rapid growth up top.
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That will probably be a never ending battle. Better to cut your losses. Re-graft low.
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Blacknot can be fought and will be fought. These trees are around on there 3rd or 4th leaf in the ground. 3 plums between 16 grafts. This will be the year and the no blacknot is going to stop that.
Same here, I cut out my Methley 2 years ago.
Iām not sure if this retired Cornell professor is mentioned in this thread,but I was looking for some information on Blossom Blight and found this article.In the last paragraph,he mentions Chlorothalonil as the best product to prevent Black Knot.bb
http://blogs.cornell.edu/plantpathhvl/2014/05/08/preventing-brown-rot-blossom-blight/
I have a delema with one of my multi-grafted trees. Black knot is coming out on it and I donāt think it will be practical cutting it out. One problem is the scaffold of the tree I believe is Morris. Whatever it is it is Black knot prone. To make things worse I have had late Frostās the last two years so I havenāt had a chance to taste the plums on it. One Iām especially curious of is Howard Miracle but it also has Satsuma, Toka, emerald beauty, Sprite, delight, burgandy and more. I would like to eat the fruit before removing the tree if the galls wouldnāt spread spores before then. Iām including some pictures to help determine if the galls will spread spores this season.
As you know I am cutting back all the suspected blacknot now and spraying it with kocide and Chlorothalonil. I have had blacknot on likely most of 16 graft and I only tasted 3 plums so far. I will be stepping up my dormant spraying and next winter for sure.
Iām going to re ask the question hoping someone knows the answer. Will the galls in the above pictures release spores this summer? The ones on the trunk I could cut out. The small branches are gonners in my book. I wonder if I could wrap the small ones in electrical tape to buy time. I would like to get scions wood off them to make a new tree next year. The black or is on the scaffold not the grafted branches.
Getting scion wood off a known plum that is prone to black knot is probably asking for more black knot in the future.
Itās only the scaffold that is prone. The varieties are fine as well as the rootstock. Thatās why I will cut it down. I just want to delay cutting it to get some fruit and scions providing the galls donāt spew spores. That is the reason for the original question; Will these galls release spores this year?
Still thanks for replying.