Help for chewed up common beech - Ask Extension
I have a 25 year old beech tree whose leaves were partially chewed up by mossy caterpillars. It was not completely defoliated, but I do not see it rec...
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Help for chewed up common beech #878678
Asked July 25, 2024, 6:51 AM EDT
I have a 25 year old beech tree whose leaves were partially chewed up by mossy caterpillars. It was not completely defoliated, but I do not see it recovering very well. I've soaked it and am considering some kind of granular fertilizer. Do you have any suggestions. Thanks, Dave
Kalamazoo County Michigan
Expert Response
Hi Dave, Thank you for your inquiry. Can you please send pictures of the entire tree and how it sits in your landscape and also close-up images of the chewed leaves…top and underside?
When were the chewing caterpillars on your tree? Do you by chance have a picture of one, can you describe the color, size, smooth or hairy or spiny? I ask because I am not familiar with “mossy” caterpillars.
This is help me understand what’s going on with your beech tree.
When were the chewing caterpillars on your tree? Do you by chance have a picture of one, can you describe the color, size, smooth or hairy or spiny? I ask because I am not familiar with “mossy” caterpillars.
This is help me understand what’s going on with your beech tree.
Hello,
Thanks for your reply. These were Gypsy Moth caterpillars that chewed up our beech tree. Here are some photos. I'll keep watering it.
Hi Dave, Thank you for this additional information.
The tree in the forefront of image #3 doesn’t have much canopy left. If that is the beech, the spongy moths (formerly called gypsy moths) caterpillars really feasted on your canopy. The good news is that at this late in the season the leaves have hopefully supplied most of the nutrients needed for this season.
You are taking the right approach by trying to keep the tree as healthy as possible. Keeping it well watered until the ground freezes is important. The best way is to lay a hose at the base of the trunk and let it trickle for several hours a couple times a week.
If you wish to add fertilizer this year, you should do so very soon. Doing so in August or later will encourage new growth that will not be hardy this winter. I would suggest you use the fertilizer stakes that are meant for trees rather than sprinkling granular food on the ground. The stakes get the nutrients a little deeper in the soil and will last longer. Please see the information in the links below:
https://www.canr.msu.edu/resources/using-bands-to-protect-shade-trees-from-spongy-moth
https://www.canr.msu.edu/resources/dealing-with-spongy-moth-around-your-home-or-property
Here are some tips from the Michigan Invasive Species Program for controlling these caterpillars:
The tree in the forefront of image #3 doesn’t have much canopy left. If that is the beech, the spongy moths (formerly called gypsy moths) caterpillars really feasted on your canopy. The good news is that at this late in the season the leaves have hopefully supplied most of the nutrients needed for this season.
You are taking the right approach by trying to keep the tree as healthy as possible. Keeping it well watered until the ground freezes is important. The best way is to lay a hose at the base of the trunk and let it trickle for several hours a couple times a week.
If you wish to add fertilizer this year, you should do so very soon. Doing so in August or later will encourage new growth that will not be hardy this winter. I would suggest you use the fertilizer stakes that are meant for trees rather than sprinkling granular food on the ground. The stakes get the nutrients a little deeper in the soil and will last longer. Please see the information in the links below:
https://www.canr.msu.edu/resources/using-bands-to-protect-shade-trees-from-spongy-moth
https://www.canr.msu.edu/resources/dealing-with-spongy-moth-around-your-home-or-property
Here are some tips from the Michigan Invasive Species Program for controlling these caterpillars:
- Look for egg masses on tree trunks through the end of April and scrape them into a cup of soapy water using a plastic putty knife or other dull scraping tool. Egg masses are light brown, sponge-like in appearance and about the size of a quarter.
- Wrap a double band of duct tape around tree trunks beginning in late April through late May, making sure the adhesive side is facing out to prevent hatched caterpillars from moving up the tree to the leaves.
- Report spongy moth sightings to the Midwest Invasive Species Information Network online or through its smartphone app.
- Contact a local forester for treatment options through the International Society of Arborculture.
