What is the safest method for dropping large trees on high degree slopes?
Land the tree uphill -
Pro: less damage to tree
may be the best choice for weight distribution
Con: tree may slide back down hill eliminating a safe
escape path
tree may not fall far enough to seperate from stump
Land the tree accross the slope -
Pro: may be best choice for weight distribution
Con: tree may roll or slide down slope - big problem if escape path is not up slope
Land the tree downhill -
Pro: tree should not roll or slide
may be best choice for weight distribution
Con: more damage to tree from increased fall velocity
streams tend to be at bottom of slope
bole may kick up violently
if tree spans ravine large stresses may develop in bole
and you are faced with a whole new set of problems
Felling (falling) a tree on a slope is dangerous and tricky business but sometimes it must be done. We did not cover this in the Cutter I & II classes I took. ( or if we did my mind was off wandering through the woods ::) )
Advice from the pros?
Usually on cable yarding units the trees are fell across slope. The stumps and retained trees help keep them from rolling, also they are not limbed too clean. The limbs help prevent rolling as well.
Uphill falling is labor intensive and dangerous but needed at times. Straight down hill will put the logs in the bottom of the canyon a little to often and really breaks things.
OWW,
I have often pondered the same question and don't really know a good answer. There are a lot of things that influence which way you fell the tree besides the slope.
Which way is the tree leaning, any good trees in the way, obstacles in the way when pulling the tree out?
In cutter 3 or 4 they teach a couple of bucking techniques that keep the tree top and log from rolling on slopes. They are called the top lock and tongue-groove cuts. I have used them a lot and they work. :)
Falling up hill is not good, I droped a 30" RO up a hill once. It stoped sliding when it got to the bottom of the slope and on a state rd :o. 2nd car by, a statey :'(. I try to drop sideways a little up or down depending on skid options and use the T & G cut.
Ed
OneWithWood, the best thing to do is exactly what you are doing. Analyze the situation and proceed with the safest method given the situation at hand.
hi
falling a tree on a uphill grade is not a real good idea,ive seen and heard a lot uf a lot of accedents that way
tiny
:P excuse me for asking ....But can someone explain the T&G cut . ???
Try this ...
http://www.osha-slc.gov/SLTC/etools/logging/manual/limbingbucking/examples.html#tongue
thanks , never did go to loging school , dont know that they had such a thing back then ,we learned from my dad and my grand-pa, What I did was cut the two sides and left 2inchs in the center but I see where the T&G cut would be much beter and safer ....
BTW nice site I'm going back there and read up (later )
Thanks for posting that link Kevin. Good information.
We are currently clearing a private ski slope on a 45 + degree slope on a hardwood timber harvest area.
There is currently about 8 inches of snow cover on the harvest area. Fallers started cutting from the bottom working their way to the top of the slope. Stumps were cut as low as possible and trees were felled down slope. The tops slowed them down some in the snow. Faller was sure to always work from above.
With caution they were cable skidded tree-length to the bottom where they were bucked up into products. Trees were mostly sawlog sized sugar maple, 16 - 24 inch dbh with included pole size timber.
Ron,
Is this in an area where the trees have been tapped for syrup?
Have not been to your part of the country.........but often hear of the damage by corporate gluttony to the trees.
Been reading a book called "The Dying Of The Trees" by Charles Little
The trees you mention seem small and young to be considered part of the problem he is referring to in his book.
Just was wondering..... if management decisions are being made to develop areas where weakened trees due to commercial syrup production are causing stand failure.
Oh........to get back on topic !
If there is a need to fall a tree uphill make a humboldt cut.
No, this area has not been tapped for maple syrup, but I have worked a number of areas that have been. It sure lowers the grade and value of the sugar maple where it has.
I hate to see it, but "sugar bushes" were quite popular here in the past as some still are where maple syrup is their "value" product.
Many such areas are being fragmented into small parcels and often being liquidated for their possible timber values.
The actions the loggers took on the maple ski slope make sense given they wanted the trees to be bucked and loaded at the bottom of the slope.
Felling on a Slope. Loggers clear slope for private ski slope within harvest area. Fellers started at the bottom and worked upslope. Trees were fallen down hill.
A Timberjack cable skidder then skidded tree lengths down hill to the bottom flat where trees were bucked up into sawlog and pulpwood products. A Valmet forwarder then forwarded the wood products to the landing/decking area about 1/2 mile away. Lee hardwood timber harvest; 1/04.
(https://forestryforum.com/images/04_01_03/felling_on_a_slope.jpg)
Logging on a Slope. Clearing a private ski slope for the landowner. Lee hardwoods timber harvest; 1/04.
(https://forestryforum.com/images/04_01_03/logging_on_a_slope.jpg)