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MarcP2
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Infested Tree?

Here's a photo of a tree I took this summer and am just getting around to organize. It looks infested with something, but what? Does anyone know what kind of tree it is? If I find that out, maybe I can research what might be causing those strange coccoon-like bumps.

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applestar
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Re: Infested Tree?

Oh, oh, oh! :-()
My first question to helpfulgardener community was to ID a volunteer tree seedling in a flower bed that turned out to be an elm. ...this looked like elm to me and I know round bumps on my oak tree leaves made by insects are called "galls" even though these are not hemispherical...

Search for "elm gall" turned up this page:

:arrow: https://www.extension.umn.edu/garden/dia ... tions.html
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imafan26
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Re: Infested Tree?

I think they are gall wasps. The galls are an immune response by the plant in response to the insects interfering with the plant's normal cell growth. Light infestations are tolerable but heavy ones can severely distort the leaves and/or twigs and impact the health of the tree.

https://ento.psu.edu/extension/factsheets/galls-oak
Happy gardening in Hawaii. Gardens are where people grow.

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MarcP2
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Re: Infested Tree?

applestar wrote:Oh, oh, oh! :-()
My first question to helpfulgardener community was to ID a volunteer tree seedling in a flower bed that turned out to be an elm. ...this looked like elm to me and I know round bumps on my oak tree leaves made by insects are called "galls" even though these are not hemispherical...

Search for "elm gall" turned up this page:

:arrow: https://www.extension.umn.edu/garden/dia ... tions.html

Great link! I think you are right about it being an elm. I've seen a lot of galls but have never seen them clump up like that first photo. Nevertheless, that's clearly what is going on. The shape seems to be more like Elm cockscomb gall but the color and growth pattern in the last two photos looks more like finger galls. I'm still reading to figure out which one is on this tree. Thank you.

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MarcP2
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Re: Infested Tree?

imafan26 wrote:I think they are gall wasps. The galls are an immune response by the plant in response to the insects interfering with the plant's normal cell growth. Light infestations are tolerable but heavy ones can severely distort the leaves and/or twigs and impact the health of the tree.

https://ento.psu.edu/extension/factsheets/galls-oak

Yeap, this tree has a lot of gall. I had no idea they developed in such clusters.

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