Sudden Leaf Yellowing on Fruit Trees - Ask Extension
Hello! I am a small organic orchard of about 60 trees. Overnight this week, my tart cherry tree started yellowing and dropping leaves. Seeing a few...
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Sudden Leaf Yellowing on Fruit Trees #802453
Asked July 22, 2022, 11:30 AM EDT
Hello! I am a small organic orchard of about 60 trees. Overnight this week, my tart cherry tree started yellowing and dropping leaves. Seeing a few apples trees and also peach trees doing the same thing, much less extreme (detailed leaf photo shows 2 apples on left, cherry on right). No sign of insects or diseases I am used to seeing. I've had about 4" of rain in the last ten days...in my clay soil thinking this is over watering? TY! Susan
Washtenaw County Michigan
Expert Response
Susan, Sorry this took so long. Someone was too busy to answer or reassign. I just received this at lunchtime.
My first thought when I read your email was Cherry leaf spot on the tart and apple scab on the apples. I close look at the pictures changed my mind.
The yellow leaves on the apples is Necrotic leaf blotch
Necrotic leaf blotch - Integrated Pest Management (msu.edu)
I have seen this many times when we have a hot dry spell followed by heavy rain. There are wide variety differences between varieties, Yellow Delicious and Macintosh and their offspring are the most susceptible varieties. I attach one of my photos since the ones in the link do not really resemble yours that closely.
I assume that the tree in the photo is one of your tart cherries. What variety is it? The trunk does not look like any tart cherry I am familiar with. The leaves look right, but lack the nectar glands at the base of the leaf blade at the leaf petiole that are fair common on all cherry trees. The bark of the twigs and the buds on the twigs look right. Cherry leaf spot cause small black spots on the leaves and then the leaves turn yellow and fall off the tree. Bacterial canker causes larger black spots on the leaves which often fall out of the leaf later in the season many of the leaves will turn yellow and fall of the tree. This link is to a search page at MSU set for bacterial canker. It is a disease of cool wet springs, which we certainly had this year. A copper spray in the early spring would be a good organic control.
Search - Integrated Pest Management (msu.edu)
My first thought when I read your email was Cherry leaf spot on the tart and apple scab on the apples. I close look at the pictures changed my mind.
The yellow leaves on the apples is Necrotic leaf blotch
Necrotic leaf blotch - Integrated Pest Management (msu.edu)
I have seen this many times when we have a hot dry spell followed by heavy rain. There are wide variety differences between varieties, Yellow Delicious and Macintosh and their offspring are the most susceptible varieties. I attach one of my photos since the ones in the link do not really resemble yours that closely.
I assume that the tree in the photo is one of your tart cherries. What variety is it? The trunk does not look like any tart cherry I am familiar with. The leaves look right, but lack the nectar glands at the base of the leaf blade at the leaf petiole that are fair common on all cherry trees. The bark of the twigs and the buds on the twigs look right. Cherry leaf spot cause small black spots on the leaves and then the leaves turn yellow and fall off the tree. Bacterial canker causes larger black spots on the leaves which often fall out of the leaf later in the season many of the leaves will turn yellow and fall of the tree. This link is to a search page at MSU set for bacterial canker. It is a disease of cool wet springs, which we certainly had this year. A copper spray in the early spring would be a good organic control.
Search - Integrated Pest Management (msu.edu)
Mark,
Thanks so much for getting back to me, I had no idea if writing would even work but am glad for this information. I was having endless arguments with myself about what was happening with the apple especially, I was wondering about necrotic leaf blotch but also wondered about scab and alternaria. Other than rust, peach scab I just don't usually deal with a lot of disease here. This season has been unprecedentedly bad; my quince trees got Nectria, they are super infected (have removed 1/3 of the trees, if they keep showing up with new infested material I might just yank them, am organic and am not confident any organic spray program can combat disease this bad), and a few pears had a few fireblight strikes, I have never had fireblight here in 15 years of growing.
The cherry is "North Star".
Thanks again for the info. I will work with the copper for cherry and see if I can find some organic zinc for the apples next year, seems the ship has said for 2022 on any kind of control. Kind regards, Susan
Mark,
Hello. I'm back at it with this question. Other trees also defoliating, an obscure variety called douglas wormless, Delicious and Hooples are is the worst but also seeing similar leaves in winecrisp, priscilla, liberty and haralson. Here's a couple of images. Do we think this is all necrotic blotch? Not sure of the parentage of some of these trees. Wondering if any could be the new disease Marsonnina, the blotches are a bit different on these other trees.
Any thoughts would be appreciated, thanks. Susan
On Monday, August 1, 2022 at 04:04:08 PM EDT, Susan Fancy <<personal data hidden>> wrote:
Thanks so much for getting back to me, I had no idea if writing would even work but am glad for this information. I was having endless arguments with myself about what was happening with the apple especially, I was wondering about necrotic leaf blotch but also wondered about scab and alternaria. Other than rust, peach scab I just don't usually deal with a lot of disease here. This season has been unprecedentedly bad; my quince trees got Nectria, they are super infected (have removed 1/3 of the trees, if they keep showing up with new infested material I might just yank them, am organic and am not confident any organic spray program can combat disease this bad), and a few pears had a few fireblight strikes, I have never had fireblight here in 15 years of growing.
The cherry is "North Star".
Thanks again for the info. I will work with the copper for cherry and see if I can find some organic zinc for the apples next year, seems the ship has said for 2022 on any kind of control. Kind regards, Susan
