D. Fir Stump question

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ArtB

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renton wa
Home backyard had about 20 old D Fir stumps when I bought the property in 1971. There apparently was a really nice big grove here back then. It was originally logged in 1917. Also have 32 acres near St. Helens logged in 1895 and again in 1969. Also a few hemlock stumps.

The question is the relative rot rates of D. Fir stumps.
Ihave one stump that is still about 8 ft dia, a number near that size, and a few just in the 4 ft dia (est orig tree minimum at 6ft DBH)

In 1971, a D2 cat against event he smallest stump at ground level would not budge, had to dig them out with that smal lmachine (10,000or so #).
When I got a Ford 4500 backhoe a few years back, I tried it out on some stumps. The hemlock could pretty much be chewed apart with the hoe, and a few of the D.Fir.

However, even some of the smaller 4 ft D Fir were still solid, Sawed a couple off abut 3 ft above ground (all had springboard notches still visible at about 5-6 ft high) and counted 440 rings on one till I hit the outer foot or so of rot moving inwards.
Dug up a couple of 18" dia roots about 2 ft down and they were still solid - zero rot.

Had 2 of the solid stumps about 8 ft apart, so tried the constant pull technique - 6 ton 3 sheave roller cahin come along on 8" block with 3/4" choker. Heard this would pull stumps over a period of tightening the comealong over a period of a few months. ---never even able to take up any more on the come along after the first few days..

So the question - what is the rot time for D.Fir stumps? do we in America even have sufficient time on the continent to measure it?

Extrapolating the root and my biggest 8 ft stump, which was cut about 10 ft up, it will be another 4-500 years to rot naturally?

The hemlock stumps from 1890 are pretty much all gone, it does not appear that there were many DFir over 6 ft dia down on the St. Helens property, so hard to tell from those as have not dug any up and are mostly 5 ft high moss mounds (only have an old JD440 there for thinning, no backhoe for 'chewing').
 
A D2 against a 1' dbh stump would not budge it. We had a D2 on the ranch growing up, I loved the little dozer. Anyway we don't get the rain WA does but Douglas-fir (and redwood) stumps that big are still pretty solid. (No fir stumps bigger than about 4' dbh here.) When I find one I like to harvest some fatwood for tinder. The big fir stumps can also make a good tailhold.

So in conclusion... I have no idea. But you could use a stump splitter, a D8 or bigger with a BIG spitting wedge in place of rippers. I've never seen one in person but the few pics I have seen show a pretty cool looking machine. A 50,000 lb excavator should dig out the stump in air conditioned style.
 
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Explosives. If we're in a hurry to clear a piece of ground we've found it to be very effective. Noisy, but effective.

A lot of blasting companies don't advertise much to the general public but your local sheriff's office will have a list of them.
 
yup, defanitly, back in 83 when i was in the N.G we were putting a trail head in for the blm on the east side of mt jefferson, had tree real big doug's we dropped then tryed to take the stumps out with two D7e's , wouldn't budge them. ended up blowing holes around the rootballs with shape charges then dropped in bundels of c4 . some cleanup with the cats no more problem.
 
If you're waiting for them to rot, you'll be rotten before they will.
You could try char pitting them. That's what the setttlers did and they cleared a lot of fir stumps that way. As far as I know it only works on fir.
How?
Dig out a good hole underneath the stump and get a fire going when it is burning good and into the stump, cover it over with dirt. When ever you see smoke shovel more dirt over it. Don't let it smoke or it will go out. It will smolder and works its way out the roots and after several months all that will be left is the part above ground.
 
On the west coast we'd hang our skyline on old fir stumps that were logged in the early 20's-50's. 6-10 dia ...we tied them back for regulation but it was not even close to being necessary. Pretty good force on the stump with 1,600m of skyline and a down hill yard (shotgun) (15,000lb turns). Bark would still be on them and as soon as you put a saw to them to notch you'd get nice clean chips. ....solid and hard like nails. Big bastard tap roots on those which you won't budge with anything less than a D8 or explosives....or dig and rip with a 30 ton+ excavator (Cat 325).

That said the only place I see fir stumps break down fast is inland where it is dry. This area you can't count on a fir stump lasting 10yrs or more at least for use as tailholds for cable logging. Ants and root disease do away with them fast.
 
Since I work in Renton I can pretty much guess there'll be no blastin or burnin:msp_sad: Stump grinder will be much the route you'll have to take. Now down around St Helens you may be able to blast!
 
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