My Snowsweet apple tree has a lot of yellow leaves with spots? I’m not sure if it is because of the drought here or if it is a disease. My other trees look fine. We soaked the tree today. Should I spray it with a fungicide? Will drought cause that? The leaves were not wilting. Sorry I can’t send pix.
I don’t think so, a search draws up nothing about BLS on apples but you can look up shothole diseases on apples. I did and came up with nothing. If serious water deficits occur, the trees will certainly begin shedding leaves.
Thanks. Hopefully the water will help.
Pictures?
Maybe apple scab or cedar apple rust? Scab is common on apples in places like WI.
It doesn’t look like pictures of scab. We’ve had some CAR in the past, but I don’t think that is it, either.
My apples always have a few leaves that yellow with a spot or two. It hasn’t ever been enough for me to worry about.
I would say this is about half the leaves on the tree that are yellow with dark spots.
My guess without seeing pics, Marssonina leaf spot.
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I was about to suggest that … either Marssonina leaf spot or scab, more likely the former since it seems to cause more yellowing of the whole leaf.
Because he suggested BLS I was thinking shotholes, but he didn’t say anything about that. Here are some good apple leaf pictures of MSB. It is rampant in low sprayed trees in our region now. I had to develop my own spray program for it because Cornell doesn’t really deal with non-commercial, low-spray production.
Two sprays a month apart with either Rally (myclobutanal) or Indar mixed with Captan at highest rates, starting early July have worked for me. I also use Topsin M now, which is quite affordable and systemic. I wonder if it wouldn’t work alone. I’m afraid not to use myclo or indar in the mix because they have some kickback and I use so much less sprays than suggested by Cornell. Check the link.
I am trying Immunox alone and will report results. I read up on Captan and just don’t want to personally deal with it. I hope someone is trying organic fungicides on this beast.
I did the first spray at the beginning of July. Immunox + Captan. No sign of burn on apples.
We have a drought. I think it might help lessen severity of any fungal and bacterial diseases this year.
I wouldn’t wish this on an enemy- 10-12 sprays! “Recent research from Germany (Bohr et al. 2018) shows that for organic orchards 10-12 sprays per year of each product: acid-clay Myco-Sin, or Funguran (copper hydroxide), or Curatio (lime sulfur), or sulfur, provide good control if first spray application is started around 10-12 June.”
That’s from the link I provided- and he is referring only to MLB for all those sprays. The man who wrote it was excited by the sample I brought to Cornell several years ago, no one at Cornell had seen MLB on apples before- it likely had been here for a while when I brought it in, but it doesn’t show up in commercial orchards where they routinely do 10-12 synthetic sprays in a season and tend to keep captan on the leaves throughout.
Hambone, what did you read about Captan? I tend to think that folks are way to nervous about synthetic pesticides given how the farmers that use the most of it live such longer and healthier lives than the rest of us. Small farmers are especially likely to have lived lives of exceptionally high exposure.
Most smaller farmers use airblast mist sprayers that create a fog that lingers on still days as they drive back and forth in their fields in open tractors. Labels only call for long pants, boots, hats and gloves, but do you think the older farmers bothered with that on hot days much back before people worried much about it? Even if they did, they were still wearing it on their faces and breathing it into their lungs. It is the older farmers that would have the most impact on mortality rates, I think, although I’m no expert on statistics.
I forget the details that I read about Captan but it spooked me. What protective gear do you wear when spraying Captan? Trying to protect my eyes that have glaucoma but goggles get fogged up.
Use a face shield if that worries you and only spray when it’s still. Captan – toxicity, side effects, diseases and environmental impacts
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withdrawn.