Maple Tree with Yellowing Leaves - Ask Extension
I have a volunteer maple which I hope will grow into maturity. It's starting in a good spot and is 2-3 years old. This year, I'm noticing that a ...
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Maple Tree with Yellowing Leaves #871357
Asked June 03, 2024, 3:33 PM EDT
I have a volunteer maple which I hope will grow into maturity. It's starting in a good spot and is 2-3 years old. This year, I'm noticing that a number of leaves closest to the trunk are starting to yellow and wilt. The yellowing patterns seems to be extending up and out. I've attached a picture of the leaves and the tree in its environment. It's growing in a garden with a bunch of sweet woodruff and irises around it. What do you think is wrong with it and what do you recomment for treatment?
Boulder County Colorado
Expert Response
Your maple appears to be suffering from iron chlorosis, which is common in our alkaline Colorado soils. While we have sufficient iron in our soils, it is bound up due to the alkalinity. This can be exacerbated by soil compaction or overwatering, so check the moisture of the area around the tree to be sure it is moist and crumbly but not soggy.
Since it is likely chlorosis, we are including an article on the subject, which also talks about treatment. We would recommend following the suggestion to use chelated iron.
https://planttalk.colostate.edu/topics/weeds-cultural-problems/2121-iron-chlorosis-trees/
https://cmg.extension.colostate.edu/Gardennotes/223.pdf
Since it is likely chlorosis, we are including an article on the subject, which also talks about treatment. We would recommend following the suggestion to use chelated iron.
https://planttalk.colostate.edu/topics/weeds-cultural-problems/2121-iron-chlorosis-trees/
https://cmg.extension.colostate.edu/Gardennotes/223.pdf
Hi and thank you and…
It seems that one of the distinguishing features of iron chlorides is that the veins of the leaf stay green. That is not the case with this tree. The leaves fully yellow and the ones closest to the trunk are infected. I’m wondering about whether it might be a nitrogen problem after reading the info - would a higher nitrogen content fertilizer help as well as clearing some of the plants around the tree out?
Thanks again for your help,
Robin
Hi Robin,
Please bring a sample of the leaves into the Boulder County Extension office in the Boulder County Fairgrounds on Nelson road in Longmont. It is really tough to diagnose the problem without seeing a sample. Could you also please resend the photos to us directly at <personal data hidden>
Molly H and Pat B
Boulder County Master Gardener Diagnostic Team
Please bring a sample of the leaves into the Boulder County Extension office in the Boulder County Fairgrounds on Nelson road in Longmont. It is really tough to diagnose the problem without seeing a sample. Could you also please resend the photos to us directly at <personal data hidden>
Molly H and Pat B
Boulder County Master Gardener Diagnostic Team
