Crispy maple leaves

muddslinger

Hi All,
I've got a couple of Japanese Maples that should be changing color now. Instead the foliage is turning brown and curling up. We've had one frost so far this season, about 28-30f. I didn't do anything to protect them as I figured it would help trigger dormancy. I have a couple of lace leaf maples that are not showing these symptoms.The browning began shortly after the frost. There hasn't been one since.
I can post pics of the foliage if it will help.
Are my maples dying?
Thanks for any insight.
Best,
Kevin

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Carl_Bergstrom

Hi Kevin,

I wouldn't worry. This happens sometimes, without ill effects. I don't know exactly why. Any ideas would be welcome.

Best regards,
Carl

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In love with trees

muddslinger

Thanks Carl,
That's a relief. These are my first two maples and they've really made a lot of progress this year. I'd hate to loose them. The twigs and next year's bud all look healthy.
Best,
Kevin

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BillStruhar

The proof is in the pudding... er... axils. Take a close look at the buds in the axils of the leaf stems of good leaves and bad leaves. Those of the good leaves are hard, shiny, probably reddish in color, are healthy. Those that are dull brownish are suspect. A good sign is leaves which "die", and fall off on their own. Leaves which get ugly and hang on the tree for a long time are a sign that the leaf has NOT completed its mission and been terminated by the tree, but has died of other causes. Normally, leaves do not die suddenly, they "die" of "starvation" or desiccation when the tree roots stop sending nutriments to the leaf to convert into root food, usually as a result of the leaf failing to process a surplus of food, either because the leaf has reached the end of its useful life "...best if used by... autumn" in the case of normally deciduous trees, or whatever the normal life span is for a given genera, often 12 months to 60 months for many kinds of "evergreen" trees.
Anyway, if the buds look good, DO NOT remove the ugly leaves. Sometimes, the cause of death of a given leaf is not a tree disease or mechanical damage problem, but is a leaf problem. Many kinds of trees do not shed their “dead” leaves until spring, some Oaks and Beeches among others. The “dead” leaves protect buds in the axils and are shed after those buds are mature and/or able to proceed to the next stage of life for them- expanding in spring. If the buds look good, assume the leaves hanging on are useful to the tree.

As an aside, all of the above pertains to leaf reduction via denuding (leaf trimming) too, and is why you cut the leaf at the petiole and leave a generous petiole stub which protects the immature bud in the axil until it’s darn good and ready to expand.

muddslinger

Hi Bill,
Thanks for your very informative answer.


I was concerned that this might be the case and that it might effect the winter hardiness and vitality next spring. I haven't removed any leaves. The buds appear to be healthy. I've given all my trees a shot of 0-10-10 and plan to give them at least one more before they go into winter storage. Will this help? Is there anything else I can do to to ensure their survival?
Best,
Kevin

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BillStruhar

Don't feed trees unless, and until they are ready to grow. Hold your fire until Spring (July in ME).