There is a good chance this damage is caused by the Maple Petiole Borer (Caulocampus acericaulis).
Adult sawflies (non-stinging wasps) lay their eggs in the leaf petiole (stem) of the maple leaves. They most frequently target Sugar (Acer saccharum) and Norway (Acer platanoides) maples. After hatching, the 1/3"-long, cream-colored larva, tunnel through the petiole for 20-30 days. They disrupt connective tissues, which causes the leaf to suddenly drop. Shriveled, dark-colored petioles connected to the green leaf are easily identifiable.
Don't worry. Maple Petiole Borers normally damage about 10% of the leaves. They rarely affect more than 25% of the canopy. Healthy trees can easily recover from an infestation of this magnitude. Feeding damage subsides in a few weeks.
Don't spray. Using insecticides is not recommended due to the high cost. It is also difficult to cover the entire canopy, and necessary equipment isn't available to the average property owner.
Don't bother. Raking up the leaves for aesthetic reason is an option; however, raking will not reduce infestations (the borers are in the petiole still attached to the tree). Removing petioles after they fall (approximately 10 days after leaf fall) is tedious and not guaranteed to be effective. Adult sawflies may fly in from adjacent areas to lay eggs next spring.
Keep the tree healthy. Preventative care is the best choice. Keep the tree properly pruned, watered, and protected from physical damage. Fertilize if nutrient deficiencies are detected in a soil test.
2007-06-01 17:21:54
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answer #1
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answered by Christy 4
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Do you see maple leaves unexplainably dropping in late May or June? Although this may be the result of drought, squirrels, or aphid infestations, there is a good chance this damage is caused by the Maple Petiole Borer (Caulocampus acericaulis).
Identification and biology:
Adult sawflies (non-stinging wasps) lay their eggs in the leaf petiole (stem) of the maple leaves. They most frequently target Sugar (Acer saccharum) and Norway (Acer platanoides) maples. After hatching, the 1/3"-long, cream-colored larva, tunnel through the petiole for 20-30 days. They disrupt connective tissues, which causes the leaf to suddenly drop. Shriveled, dark-colored petioles connected to the green leaf are easily identifiable.
What can you do?:
Don't worry. Maple Petiole Borers normally damage about 10% of the leaves. They rarely affect more than 25% of the canopy. Healthy trees can easily recover from an infestation of this magnitude. Feeding damage subsides in a few weeks.
Don't spray. Using insecticides is not recommended due to the high cost. It is also difficult to cover the entire canopy, and necessary equipment isn't available to the average property owner.
Don't bother. Raking up the leaves for aesthetic reason is an option; however, raking will not reduce infestations (the borers are in the petiole still attached to the tree). Removing petioles after they fall (approximately 10 days after leaf fall) is tedious and not guaranteed to be effective. Adult sawflies may fly in from adjacent areas to lay eggs next spring.
Keep the tree healthy. Preventative care is the best choice. Keep the tree properly pruned, watered, and protected from physical damage. Fertilize if nutrient deficiencies are detected in a soil test.
For more info check the site below.
2007-06-02 01:53:05
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answer #2
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answered by JoJoely 3
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if you have whole branches that have all green leaves, you've waited too long.... you stand to lose the shape of the tree if you remove all of a branch.... I have a Butterfly variegated maple that has , here and there, tufts of all green leaves... those I don't mind removing as I see them as their loss doesn't change the overall look of my tree... not as much as removing a whole branch would.... if I were you, I'd try to find an expert in Japanese Maples and consult with that person on what to do with your particular kind of tree to do right by it......
2016-04-01 10:37:42
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answer #3
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answered by Anonymous
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You can only stop it (maybe) if you know why it's happening. Get a certified arborist out to have a look at it. Then, hopefully, you'll know what you're dealing with and if there are options to treat it.
2007-06-01 16:46:20
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answer #4
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answered by Anonymous
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water them
2007-06-01 15:58:17
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answer #5
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answered by glenn t 7
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WATER and lots of it
2007-06-01 17:14:06
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answer #6
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answered by hey1yall 1
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staple them back on ... or duct tape
2007-06-01 15:57:14
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answer #7
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answered by WilljClinton 4
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