EP was kind enough to include a photo of a pair of blowdowns that he and his wife encountered on their recent hike from Wahclella Falls parking lot to Wauna Viewpoint [1]. With a few hours free this afternoon, I packed up my tools again and went to have a look.
1) EP's photo from 12/30
2) A and B obstruct the trail, which can bee seen in the lower right corner. A lays on top of B which lays at right angles across humongous C at about X. C itself fell downhill diagonally a few years ago. C's bark is still intact though the impact of B has crushed and separated it near the contact point. Since C is sloped downhill, it is likely that AB would have slid downhill along C after impact were they not stopped by upright tree D, which is living but in a decayingly unhealthy point in its life. From the scraped and gouged side of D, it appears that as AB fell, one or both struck the side of D. D is missing bark starting about 4 feet above where AB currently contact it. Anyway, D now keeps AB from sliding down along C. E and various saplings 's' are not engaged.
3) The crowns of AB extend to out of the frame to the left. They do not touch the ground, meaning their entire weight is cantilevered beginning at X. It is the weight of A and B's lower trunks and (possible) remnant tethering of their rootballs that keep the crown ends suspended (10-20 feet) above the slope. Indeed, when I shimmied out along them clearing branches to disengage the two and so I could better assess the lay, they eventually started bouncing, at which point I did not soil my pants as I should have, but retreated nonetheless. What all this means is that there is a huge amount of energy stored in the trunks at fulcrum C. Neither A nor B contact F, meaning that D alone feebly prevents A and B from sliding downhill along C. If/when D topples, E and F will likely stop A and B from sliding too far. But maybe not, and that is the true catch.
4) Dangling branches 1, 2, and 3, perhaps from A and B can be seen high up in D and E, along with others. While D and E are not immediately trailside, if either D or E are disturbed, the dangling branches could easily be flung anywhere within a radius that includes the treadway and potential work areas.
5) root ends of A and B. Old stump O.
6) A and B upon arrival. The gap between A and B is about 16 inches.
7) Branches along A and B obscure sighting up their lengths.
8) Crown ends, branches trimmed; A does not contact F.
9) View from the trail. Note the straight lay of A.
10) Detail of A and B resting against D
11) start of first cut on A
12) 1st cut finished, root end did not drop through.
13) 2nd cut nearly finished, snow, with camera flash
14) Root end drops, crown end remains balanced (on B at D)
15) 18 incher.
Gorge 400, Site #1, 12/31 & 1/31 (trailwork final)
Gorge 400, Site #1, 12/31 & 1/31 (trailwork final)
Last edited by mcds on February 8th, 2013, 4:53 pm, edited 4 times in total.
- retired jerry
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Re: Gorge 400 12/31 (trail work)
Those are huge. Amazing you can get them with that saw. Nice sequence of pictures.
"What all this means is that there is a huge amount of energy stored in the trunks at fulcrum C"
I know what you mean, sometimes when you make the last cut, it releases that energy quickly and you better not be in the way.
My stomach is getting queasy.
Possible headline in newspaper: "trail maintainer in hospital after tree whips around and smashes into him"
"What all this means is that there is a huge amount of energy stored in the trunks at fulcrum C"
I know what you mean, sometimes when you make the last cut, it releases that energy quickly and you better not be in the way.
My stomach is getting queasy.
Possible headline in newspaper: "trail maintainer in hospital after tree whips around and smashes into him"
- BrianEdwards
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Re: Gorge 400 near 777 Tanner Creek 12/31 (trail work)
That's some serious calorie-incinerating work.
Clackamas River Waterfall Project - 95 Documented, 18 to go.
- Eric Peterson
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Re: Gorge 400 near 777 Tanner Creek 12/31 (trailwork)
It's still waiting for the final cut. Loose branches still hanging in the trees above.
Re: Gorge 400 near 777 Tanner Creek 12/31 (trailwork)
Amazing work mcds! Thank you very much (I crawled under there twice this month in the dark - even the "Lower" Tanner Butte is a long way!).
Some people are really fit at eighty; thankfully I still have many years to get into shape…
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Re: Gorge 400 near 777 Tanner Creek 12/31 (trailwork)
For those interested in what trail work has been done in the past year and want to know what the PCTA Mt. Hood Chapter does on its 211 miles from Brittenbush to Mt. Adams, plus other trails in the Gorge, we have our annual meeting Saturday Feb. 2nd at the Gifford Pinchot NF HQ 10600 NE 51st Circle in Vancouver from 1-3pm. 2011 thru-hiker, "Wired" recounts her experiences along our section of the trail and how the 2,650 mile PCT inspired her to become a trail maintenance crew member and the experiences she's had on those crews. We have coffee and cookies and hope to see you there.
Re: Gorge 400 near 777 Tanner Creek 12/31 (trailwork)
Thanks Peder!
Ron - Sounds like a good time. To get more views, maybe post it in its own thread somewhere. Or maybe the mods will move it for you.
1) cleared
1
2) Once upon a time, A and B obstructed the trail, which is in the lower right corner. Their rootwads entangled, A rested on top of B. In turn B rested at right angles across humongous log C at position X. Years ago, C had fallen downhill diagonally. C's bark was still intact, though the impact of B had crushed and separated C's bark near the contact point. Since C sloped downhill, it was likely that after the initial impact, A-B would have slid downhill along C were they not stopped by upright tree D. D is living but in a decayingly unhealthy point in its life. D is missing bark starting about 4 feet above where A-B currently press against it. From the scraped and gouged side of D, it appears that as A-B fell, one or both struck the side of D. Anyway, D kept A-B from sliding down along C. Tree E and various saplings 's' are not engaged.
A month ago, on 12/31, I cleared A. Yesterday, on 1/31, I cleared B. Given how close X was to the trail, it was nearly certain that B would see-saw once cut: the crown end would fall the ~20 feet to the ground, while the trunk end would rise above the trail, hopefully above head height. Log A added to this fortuitously uneven distribution of weight, because A rested on B not at X, but farther out towards the crown end, at a point near D. At the start of the work yesterday, the main question was whether the see-sawing would be the only movement. The distribution of weights on either side of D relative to the friction of B on C was less clear. Once B was cut at the trail, it was possible that 1) A and/or B would pivot around tree D, with the trunks sliding down along C and 2) the crown ends would swing uphill before they had a chance to fall to the ground. It was also possible that the released energy would cause D to topple. I thought both of these scenarios unlikely, but couldn't argue that either or both wouldn't occur.
3) To push the odds farther in my favor, I cut off branch K from B. K pointed downwards at an angle. K could delay/prevent the crown end from reach the forest floor, and also induce the unwanted pivoting.
3
4) I cleared the bark on the top and sides with a 3.5lb axe, and chopped into the sides of the log (which would measure out as 28" in diameter at the cut) to narrow the length of the kerf to about 24", which would help clear the sawdust during sawing with my 42" commontooth blade. Uncleared sawdust creates a huge amount of friction. The best orientation for a crosscut is vertical. If the log is horizontal, that works well. Given the pitch of the log, I opted for a compound angle in order to reduce the likely hood of the ends binding up in a jam once the cut was completed.. This was a trade off, an acceptance of more friction, less efficiency, and a longer cut. As I worked away, I was soon relieved to hear crackling after my kerf was a mere 4-5" deep into the 28". I read the early crackling to indicate a huge imbalance in weight about the fulcrum.
4
5) progress
6) the kerf opened as I work my way through the log
5
6
7) With about 6" remaining to cut, the log gave a loud crack. Both ends raised as the split progressed. At a height of about 5 feet, the rootwad end fell back down, and the crown end continued up to a resting height of 7 feet 4 inches. I kind of watched this play out, but truthfully I was focused on pulling my saw clear, backing up, then turning to headed uptrail out of the way.
7
8) Still a bit of work left. This was the only point at which I needed a wedge, seen on the far right
8
9) From clearing the maple treee down trail, V' served as a bearing to slide the 12' long, 200lb slab downslope, then as a lever to swing the thin end off to the side.
9
10) By tooth count, it scales to 28".
9
11) work worth doing
11
12) On the short hike out. More fish scales from the Bower Collection
12
Ron - Sounds like a good time. To get more views, maybe post it in its own thread somewhere. Or maybe the mods will move it for you.
1) cleared
1
2) Once upon a time, A and B obstructed the trail, which is in the lower right corner. Their rootwads entangled, A rested on top of B. In turn B rested at right angles across humongous log C at position X. Years ago, C had fallen downhill diagonally. C's bark was still intact, though the impact of B had crushed and separated C's bark near the contact point. Since C sloped downhill, it was likely that after the initial impact, A-B would have slid downhill along C were they not stopped by upright tree D. D is living but in a decayingly unhealthy point in its life. D is missing bark starting about 4 feet above where A-B currently press against it. From the scraped and gouged side of D, it appears that as A-B fell, one or both struck the side of D. Anyway, D kept A-B from sliding down along C. Tree E and various saplings 's' are not engaged.
A month ago, on 12/31, I cleared A. Yesterday, on 1/31, I cleared B. Given how close X was to the trail, it was nearly certain that B would see-saw once cut: the crown end would fall the ~20 feet to the ground, while the trunk end would rise above the trail, hopefully above head height. Log A added to this fortuitously uneven distribution of weight, because A rested on B not at X, but farther out towards the crown end, at a point near D. At the start of the work yesterday, the main question was whether the see-sawing would be the only movement. The distribution of weights on either side of D relative to the friction of B on C was less clear. Once B was cut at the trail, it was possible that 1) A and/or B would pivot around tree D, with the trunks sliding down along C and 2) the crown ends would swing uphill before they had a chance to fall to the ground. It was also possible that the released energy would cause D to topple. I thought both of these scenarios unlikely, but couldn't argue that either or both wouldn't occur.
3) To push the odds farther in my favor, I cut off branch K from B. K pointed downwards at an angle. K could delay/prevent the crown end from reach the forest floor, and also induce the unwanted pivoting.
3
4) I cleared the bark on the top and sides with a 3.5lb axe, and chopped into the sides of the log (which would measure out as 28" in diameter at the cut) to narrow the length of the kerf to about 24", which would help clear the sawdust during sawing with my 42" commontooth blade. Uncleared sawdust creates a huge amount of friction. The best orientation for a crosscut is vertical. If the log is horizontal, that works well. Given the pitch of the log, I opted for a compound angle in order to reduce the likely hood of the ends binding up in a jam once the cut was completed.. This was a trade off, an acceptance of more friction, less efficiency, and a longer cut. As I worked away, I was soon relieved to hear crackling after my kerf was a mere 4-5" deep into the 28". I read the early crackling to indicate a huge imbalance in weight about the fulcrum.
4
5) progress
6) the kerf opened as I work my way through the log
5
6
7) With about 6" remaining to cut, the log gave a loud crack. Both ends raised as the split progressed. At a height of about 5 feet, the rootwad end fell back down, and the crown end continued up to a resting height of 7 feet 4 inches. I kind of watched this play out, but truthfully I was focused on pulling my saw clear, backing up, then turning to headed uptrail out of the way.
7
8) Still a bit of work left. This was the only point at which I needed a wedge, seen on the far right
8
9) From clearing the maple treee down trail, V' served as a bearing to slide the 12' long, 200lb slab downslope, then as a lever to swing the thin end off to the side.
9
10) By tooth count, it scales to 28".
9
11) work worth doing
11
12) On the short hike out. More fish scales from the Bower Collection
12
- Eric Peterson
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Re: Gorge 400 near 777/Wahclella 12/31 & 1/31 (trailwork fi
7' 4'', not sure Crusak can fit under that!
Nice work sir!
Love how the trunks are just jutting out like that too, modern art at it's finest I'd say
Nice work sir!
Love how the trunks are just jutting out like that too, modern art at it's finest I'd say
- acorn woodpecker
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Re: Gorge 400 near 777/Wahclella 12/31 & 1/31 (trailwork fi
Just saw the final work on this today on my way up to Wauna Point. There is another large treefall on #400 about a quarter mile before the first power line clearing where two trees have fallen across relatively flat terrain. The larger one laid to rest about 4-5 ft. above the trail and the smaller one directly below it halfway between the trail and the other tree. I had to take my pack off to crawl through! If one had even a folding saw with them, they could cut the smaller one with moderate effort and then one would be able to duck through until the heavier machinery could come at a later time for the big tree. Sorry I didn't take a picture.
Just saw this thread tonight compiling some trip reports for today and last Friday and wanted to thank you for a job well done on a difficult cut, mcds.
Just saw this thread tonight compiling some trip reports for today and last Friday and wanted to thank you for a job well done on a difficult cut, mcds.