Chinese Elm Red Scale ID and Treatment

HENDO

Shohin
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Hi All,

I recently noticed what looks like a red scale on my Chinese Elms. Here are some pictures from the largest Elm which appears to be the most affected. It runs off quite easily and is powdery, but there is a lot of it on the trunk and primary branches. This particular tree gets 4+ hours of full sun a day, outside of course.

Is this for sure some sort of scale insect?

If so, how do you treat this on Chinese Elms? I've read a lot of material saying that CE do not like most insecticides/fungicides?

Yesterday I gave this big elm a pretty heavy pruning so am hesitant to do anything that would weaken it right now...

Any risk to junipers, azaleas, maples, boxwoods, all on the same benches?

Any help would be much appreciated, thanks in advance!

20200427_162607.jpg

20200427_161540.jpg
 

MHBonsai

Chumono
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Doesn't look like scale to me really...can you scrape them off and squish them?
 

HENDO

Shohin
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Doesn't look like scale to me really...can you scrape them off and squish them?
They kind of just scrape/rub off and leave a lighter bump underneath, kind of dry-ish.

Here is a section with them scraped off:

20200427_163607.jpg
 

LanceMac10

Imperial Masterpiece
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And don't be surprised if the bark flakes off in those areas....it's normal.
 

sorce

Nonsense Rascal
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I found one Red scale on my Winged elm.

1. On a winged elm.

What a pain in the ass!

Scale is just a bit more glossy than surrounding areas. A bit less porous.
It's easier to identify the texture than the look.

Sorce
 
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