Root Collar Excavation/ Stem-girdling Root Pruning thread

[Evo]

Oscillating multi tool is my go to for girdling roots. As for narrower tips you can always cut/grind the cutter to meet your needs.

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?

 

[flushcut]

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.

 

[Evo]

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

 

[southsoundtree]

STIHL BR800 RCX

Some roots from an adjacent alder.

 

[southsoundtree]

 

[Bart_]

+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

 

[The Green One]

Anyone have any before and after photos of girdling root removal on large mature trees?

Mature/Veteran Sugar Maple. Late November 2025

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.

 

[The Green One]

Part 2

 

[climbingmonkey24]

Great pics, and nice video @ATH, very helpful.

 

[southsoundtree]

How's the potassium phosphite work?

Is soil temp a factor?

 

[The Green One]

How's the potassium phosphite work?

Is soil temp a factor?

It is a plant health booster, It has fungistatic qualities and when it dissociates, the Potassium Ion is quickly available and helps with Cell Turgor.

Soils above 40F, and the product can still be absorbed for next seasons leaf out period. A good head start.

 

[peoriatreeremovalco]

Jumping in late here with our field experience in central Illinois. On mature maples we do collar excavation and girdling root work in the dormant season whenever possible — frozen ground is a nonstarter and mid-summer heat just adds stress, so late fall through early spring is the real window. For established girdling roots, we remove only the roots actually compressing the flare, favor clean handsaw cuts over power tools when the work needs to be surgical, and never take more than about a quarter of the flare circumference in a single season. The before-and-after photos posted earlier are exactly the kind of documentation that sells the next client on root work. One thing I would add for residential jobs: mulch back over the excavation site and correct the grade while you are there, because piling topsoil against the trunk after all that excavation is how the girdling starts all over again.