I haven’t had the best luck with those, certainly see the potential but I think I’m using the wrong blades. They get gummed up and quickly stop cutting any advice on the best blade?
Personally I like the carbide ones. The hardened steel ones you can take a cutoff disc and make gullets. But yes they do gum up but are easy to unclog.
One of the best root pruning tools I use for imbedded roots is a folding silky handsaw that I snapped the tip of the blade off, essentially having a tooth on the very tip
+1 broken tip handsaw. Oscillating tool can work Fein too I've re-pointed HSS blade teeth with a dremel cutoff disc. Thinner disc = finer teeth pitch to match small oscillation motion size, somewhat unlike jigsaw or such.
I Fein buzz cutted old pressure treat deck framing that was getting carried up and indenting an oak trunk. The moisture content makes the fiber chewy and can almost stop blade progress. A knot near stopped me dead. Heat, steam and binding. "deck girdled"
edit - apologies Flushcut if I presumed/misunderstood cutoff wheel to mean 4 1/2" on a grinder when possibly you meant dremel size and I'm just re-stating your post
Canopy branch loss, Wetwood, Decay and Collar Rot at base.
Investigated SGR when soil temps around 45F, Excavate and explore by hand only, remove smaller than 2" diameter as to not affect root anchoring. Drench with Potassium Phosphite at compleation.
No further issues presented in the 2026 season, And it's been super wet this year.