I have some Dunstan Chestnut trees in my yard. The leaves are dying on one of them, except for the last few on the branch. But they may die too. Wha...
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Chestnut Tree Leaf Problem #769109
Asked August 25, 2021, 1:35 PM EDT
I have some Dunstan Chestnut trees in my yard. The leaves are dying on one of them, except for the last few on the branch. But they may die too. What is wrong with it? What do I do to keep it from totally dying?
Ottawa CountyMichigan
Expert Response
David, thanks for the question.
This is unusual. This could be pathogenic but it may be abiotic (nutrient, water, heat, etc.). What is your soil like (sand, clay, loam)? Have you recently fertilized near the tree? When was the tree transplanted? Has the tree been watered? If so, how much? Do you know the pH of the soil? When did this start?
I should tell you a couple years ago I had two other Dunstan Chestnut trees die in my yard, near this one, with the same problem. I never figured out what the cause was for the other two, but this tree has been healthy until this year. It started doing this around early July and has been gradually getting worse since All three were planted at the same time about 5 or 6 years ago. I did buy another tree a couple of years ago because they need at least two to pollinate. That tree is still fine.
I thought of this a couple of days ago. I water both trees from time to time with a pretty good soaking of water from the lake behind my house. Could there be something in the water? I plan in the future to use my city water instead. I don't think I over water them because it drains pretty well with the sandy gravel soil.
I have a little tester for PH and it comes up at high 6/ low 7. A few days ago I brought a soil sample to a local coop and they sent it to Lansing for analysis. I should be getting that back early next week.
I did plant 4 of these at a farm I own 3 years ago, but one of them is starting to look a little like it too. I just remembered I bring them water weekly that I draw out of the same lake behind my house, but they don't get as much water as the ones in my yard do. I am thinking there may be something in my lake, but I do sprinkle my lawn and garden with the same water and I have not seen a problem otherwise. It has been treated the last couple years, but I think the first 2 died before our association started treating it.
I do not fertilize around this tree other than using what is recommended, Espoma Holly-Tone, in the Spring. Also, I think I spread a little ironite around this tree a couple months ago.
David, if that pH is correct you could be high for this tree but would not be necessarily a problem. Some information suggests that this tree is intolerant to salt (need to verify). This is a big problem for street trees. Bacterial scorch is another possibility. Please forward your soil test results when received. I will also make some inquiries at MSU.
The high pH is great concern. From the literature available this is well beyond the tolerance level for this tree (5.5 to 6.5). With high pH nutrient availability can be compromised. This could explain why you are having problems with these trees. High pH can come from water, concrete work, or lawn liming. bring pH down can be difficult depending on the contributing factors.
