Pictures

bugs have a way of finding stressed plants ....

and a tree that caught fire is probably stressed ....

3 years isnt much time in tree time.. which is counted in decades ...

probably one of the wooly aphid type creatures .. but i cant tell from the pix ...

but it looks awful close to the house...

it might be worth your while to have a certified arborist give you an onsite inspection of the trees overall health ... add your big city name to the link below

ken

https://duckduckgo.com/?t=ffab&q=isa+certified+arborist&ia=web

Not great images of the problem, but I'm thinking that it's a giant infestation of one of the cotton scale insects. I'll attempt to attach a link to a fact sheet for you to read and begin your investigation.

European Elm Scale

Oh you are right! How do you get rid of them?

Most references say that they generally don't cause significant harm and therefore pesticides are usually not warranted, but this webpage includes a couple chemical control options for heavy infestations.

some more recent pictures

@arbordave (SE MI) if this is easier to identify?

Sure looks like woolly alder aphid to me, with the associated sooty mold that grows on the honeydew produced by the aphids.

Thank you again!!