| From West by Northwest.org Bummers & Gummers Horses Re-Create Habitat for Cutthroat Profit By Matthew Hall, illustrations by Lokiko Hall Jun 6, 2003
The BLM, which manages forest and land and a campsite along the Alsea River, had been persuaded to perform this contract using a team of horses as the pulling force rather than a large machine equipped with a winch. The contract was awarded to Howard Pazdral of Seahorse Stagecoach, who subsequently hired me as the climber to set the rigging up in the trees. Now, Howard has yarded many logs and pulled many wagons with his horses, but never had he yanked trees over by the roots. (Oops! I tell a lie. We did it once, but that was a mistake - a near accident when we were decking logs with horses, cable, and a pulley hung in a tree. Luckily, no one was hurt.) So the challenge was for Howard to invent a system whereby two horses, with a maximum combined pull of 4,500 lbs, could exert up to 24,000 lbs of pull by way of mechanical advantage. The following article includes details of the system and variations that he found to be most efficient for this work. .
At the time it was first logged, sometime in 1940s, the banks and floodplain of the Alsea River were dominated by large mature firs and cedars broken up by swampy scrub areas. The initial logging was done using springboards, crosscut saw, and axe and removed the finest trees. This left standing a scattering of large forked and cull trees. During this logging session they most likely removed all salvageable logs already lying in the river course. The remaining uncut trees were blown down during the Columbus Day Storm of October 14th 1962, a storm that did far more damage than the storm on February 7th 2002. In many cases these blown down trees fell across the river and side streams and were cut and yarded out during a salvage operation. The net result of removing all these big logs from the river was that the streambed was eroded down to the bedrock. Like many rivers, creeks, and streams in the Pacific Northwest, the Alsea river is now confined to a trench and its former floodplain is no longer regularly inundated by the river. Such previously normal events now only occur during "100-year storms," and are more catastrophic than beneficial. We must always keep in mind that the river was in the times previous to heavy commercial logging more like a large swamp with water flowing through it than a channelized river. In fact I saw evidence of drainage ditches through the floodplain. These were probably put there to dry out the land to make it more suitable for Fir. At some point after the Columbus Day Storm, beavers moved back into this stretch of the river. Our entire work area contained much evidence of their past activities and projects. Chewed off alder and fir stumps were still visible where they had felled trees into the river. A surprisingly large amount of big firs had been girdled (had the bark chewed off around the base) or partially girdled, and some of these had snapped off at the root collar, falling across tributary streams. All beaver activity along the project area was brought to a halt by the floods of 1996, which blew out all the wood, logs, and dams that they depended on for habitat. Interestingly, the girdling work that the beaver had done was amazingly similar to what we were doing. When they girdled the larger trees, the trees would later rot at the base and of course would snap off in high winds and crash down into the river. The trees they selected for this treatment were exactly the same size as the trees that the BLM had selected for us to pull down. As I initially mentioned, this project was intended to restore fish habitat. Fish require large amounts of large fallen trees and logs ("coarse woody debris") in their stream/river system to provide structure and habitat. It's quite simple: no coarse woody debris, no fish. At this point in time salmon cannot swim up over the falls (although they've been observed trying), so our project area is the domain of the native cutthroat trout. Because there was hardly any coarse woody debris in the main channel, the river was empty of trout. The tributary streams however contain fallen logs and these were the last habitats of the cutthroat in that part of the river. The aim of the project was to put coarse woody debris back into the main river channel by uprooting existing bankside trees rather than by trucking in from elsewhere large logs with or without rootwads and installing them in the river. It was hoped that by leaving them attached by some of their roots to the ground and by weaving them together and amongst the existing riverbank alders they would not be washed out by storm/flood events as in 1996. The project was to be undertaken by horses to reduce the damage to ground conditions as well as the visible damage to the landscape that machinery would have produced. About two thirds of the project was within the park area of the Alsea Falls Campground. Along a three-mile stretch of the river 75 trees were selected. Their diameter at breast height (dbh) ranged from 18" to 34" and the average height was around 100 feet, with 120 feet being the tallest. With the aid of a cable rigged high up, these trees were to be pulled diagonally across the stream. Sometimes it was necessary to buck them and reposition them for optimum placement. My job was to climb each tree and rig it with a 60-foot choker at some point between 40 feet and 70 feet up the tree, depending on the individual tree's characteristics. The bankside roots of each tree were dug out with shovels and exposed. Howard discovered a handy tool for this called the "Nate." It is a roundpoint shovel bent over at 90 degrees with the point cut off and the edge sharpened. The head is attached to an axe handle. Next, the visible roots were cut with a chainsaw fitted out with a solid-nosed bar and triple-chromed chain. This chain will cut more soil than a regular chain before it gets dull. The 60-foot chokers were made of 1/2" wire rope (20,000 lbs breaking strength) with a keyhole on the end. The keyhole choker is very secure and won't come undone even if it is jiggled a lot. Then the tree was rigged with a choker that came down to the ground or to within 15 feet of the ground on the highest setting for the biggest trees. Another cable could be attached to this leading to the pulling equipment and the horses. (See diagrams.) The whole project was a series of steps to figure out and refine the equipment and methods so that it all worked smoothly. Howard had 30 days to accomplish this project. If we didn't do it within that timeframe the BLM would be free to deduct who-knows-what kind of penalties from the amount they initially agreed to pay. The pulling equipment that Howard came up with, after numerous discussions with old timers who had done similar work before, was christened "the Power Puller." It consisted of two plates carrying a total of five 4-inch snatch blocks. (A snatch block is a pulley that opens up to make it possible to position the cable on the pulley wheel rather than having to thread the cable through it - which would be impossible when you have any sort of device, such as a hook or an eye, on the end of your cable. For the rest of this article I will call these snatch blocks "pulleys.") Two hundred feet of 5/16ths -inch cable ran between them. In this set-up (see drawing of Power Puller), three of the pulleys are traveling and this gives a mechanical advantage of 6:1 (2:1 for each pulley). When the horses are exerting 2,000 lbs of direct pull this translates to 12,000 lbs of pull through the Power Puller. For the 10 largest trees a larger snatch block (rated at seven tons and made by Skookum, an outfit that makes forestry equipment) was hung on the end of the choker. The mainline going through it was then anchored to a tree for a tailhold. This gives you a 2:1 mechanical advantage over the Power Puller. Thus if, say, the horses were to pull at an all-out foot-slipping maximum of 4,500 lbs, you would get through the Power Puller 6:1 for 27,000 lbs of pull and then 2:1 through the Skookum for a total of 54,000 lbs of pull. (It should be noted that the horses never had to pull full out with the Skookum, if we had, we would have exceeded the breaking strength of the choker cable by more than a factor of two. Howard estimates that the horses were pulling a fairly easy 2,000 lbs when he used the Skookum.) Howard only used the Skookum on the biggest trees that he thought the horses would have trouble pulling. Using the Skookum Variation involved carrying extra cable - which is damn heavy, mind you - back and forth across the river and was much more time consuming to set up.
Mechanical advantage from moving pulleys is paid for by extra travel. The Power Puller contains 200 feet cable, which gives a take-up of 40 feet. In other words the horses pull the cable 200 feet and that gives 40 feet of pull (take-up). Although the work area was quite flat, there were enough obstacles, such as downed logs and clumps of big trees, that most of the horse trails were 120 feet long or less. Now remember that cables have to go in straight lines, every bend requires another pulley anchored to the base of a tree. (The trees all had nice broad bands of nylon around them so their bark didn't get damaged by the pulleys.) The horses' route had to be straight, as well. So we were often reduced to a 20-foot to 25-foot take-up requiring 100 feet to 125 feet of straight run for the horses. Of the 75 trees that were pulled over, about half came easily with about 500 lbs of horse pull. A few of the trees took three or four pulls to pull over. Through experience the method of setting up the pull was refined to this: First pull all of the slack out of the mainline by hand through the Power Puller and tie it off with a rope to hold tension. Then re-extend the Power Puller and clamp it to the mainline with a cable clamp. Untie the tensioning rope. Hitch up the horses, and away. Shortly after Howard was awarded the contract we met at the site and viewed the situation. We agreed that it was a lovely to place to work. The river was low (at early September levels), flowing over bedrock with alders and vine maple overhanging in graceful arches. The riversides were natural coast range regrowth forest with walking trails handily situated. Doug Maxwell was the manager of the trails and the campgrounds and had been for 27 years, helped by a crew of BLM seasonal workers. The results of his efforts were nice trails and campsites that blended wonderfully with the surrounding vegetation. While I could see that the river did need large woody debris, I couldn't help thinking that we were going to trash the place in the process, at least in the short term. Doug Maxwell certainly thought so, too. Of all the BLM people involved in setting up this project he was not in favor of it. He viewed it as a useless project that was going to needlessly tear up the park, creating hazards for people using the area, and what's more he figured it would all wash out in the next flood anyway. As Maxwell had worked at the site for nearly three decades, I thought he probably knew what the Alsea River is capable of doing in flood. We started work upstream from the campground, gradually progressing downstream into the campgrounds after they were closed to the public at the end of September. I was working my way up the fourth tree when Howard pulled over the first one, proving that his technique worked. After Howard pulled over a few trees, we started using them as bridges to cross the river. As such they were ideal, spanning from bank to bank, often in clusters of three to five. Great fun for kids to play on as soon as they discovered them. And dangerous. Well, mildly dangerous - what kid wouldn't joyfully risk falling off, possibly breaking a limb, cracking a skull or drowning, for a happy scramble over a slippery moss-covered log. But this is America, land of free-wheeling insurance companies, and that's not good. Indeed, someone from the BLM head office came out and stated that the logs were "an attractive nuisance," which is insurance talk for anything that would naturally attract attention to itself by being fun, charming, and not terribly safe. This includes everything from a donkey pulling a fruit and vegetable cart in town to a log across a river in a forest, possibly even to a tumbling-down old barn seemingly minding its own business on private property. Doug Maxwell is required to put a handrail on any structure that is over four feet above the ground. The larger trees that we uprooted spanned from one bank to the other and were often 15 to 20 feet above the riverbed in the middle. From this the question arises: Do fish habitat logs, being man-made structures, need handrails if they are located in a public campground? By the time we were through we transformed the riverbanks from a tidy, peaceful and shady place into a mess of uprooted fir trees and smashed alders, with broken branches and treetops strewn every which way. Of course, this was our goal: to imitate a "periodic disturbance." Wind and ice storms are natural events that create periodic disturbances wherein large trees are uprooted and other trees are broken and damaged in the process. I have witnessed two catastrophic windstorms and one catastrophic ice storm since I moved to this area in 1991, and I've been impressed by the amount of damage caused by these events. Now here we were working and thinking hard to imitate these natural events in a specific area. Much to the dismay of Doug Maxwell, after all, who in their right mind would invite a periodic disturbance into their work area? Having said that, though, Doug was careful that his feelings didn't impact those of us doing the work, a thing for which we were all grateful. About halfway through the project I took the fall interns from the Aprovecho Research Center out there for a site visit. (I work part time teaching sustainable forestry at Aprovecho.) When we arrived, Howard and the horses, Ruby and Roma, were all set up to pull the last tree that I had chokered. The interns were introduced to Howard and the horses, given a brief description of the rigging, and told where to safely stand for the coming pull. It was hoped that the tree would fall diagonally across the stream in a downstream direction. We were standing directly across the river and should have been safe. Just in case, I reminded everyone to pay attention and not to remove their hard hats. As the horses began to pull and the rigging tightened up, the tree began to move in the desired direction. But then it appeared to stop moving - which meant it was coming right for us! We ran. By the time its top crashed down onto the nearby concrete picnic table (showering a hard-hatted BLM official who was standing next to it with bits of branches), we were all at least 30 feet away. After lunch the interns watched Howard and the horses reposition the same tree. With the help of a pulley hung about 15 feet up a tree, the horses pulled the top of this tree about 20 feet downstream.
During the month this operation took place the BLM did a similar project on the Siuslaw River using a helicopter to position 60-foot Douglas Fir logs in the river. The logs were flown in from off site as there was nothing suitable on the riverbanks. The cost of the helicopter in monetary terms was $700 per tree. The cost of the horse operation was $450 per tree. In addition we heard it was difficult to impossible for the helicopters to accurately position the logs in the river. Furthermore, the helicopter caused a great deal more damage to the forest canopy than the horses could ever do as it lifted up to reposition the logs. We had never done this type of operation before, and for much of the job it seemed unlikely that we would finish on time. But as it turned out we finished the project two days early. It is going to be interesting to see how this all develops. Will the beavers re-colonize the area? Will they build onto the structures we've installed? And will these trees remain in place despite future storm and flood events? I am hoping I can find the time to see what develops over at Alsea. I would also like to compare it to how the logs without rootwads do over in the Siuslaw River. One final note: Are you starting to get ideas about pulling over that tumbling-down barn you're suddenly worried about or making a natural bridge across your creek? Bear in mind that apart from the off-the-shelf hardware (the pulleys, etc.), much of the equipment mentioned (such as the plate and the rings that attached everything to the plate) was specially made by a company in Junction City that also advised Howard along the way. Copyright 2003 by Matthew Hall and Bummer & Gummers To subscribe to "Bummers & Gummers" (the full zine in print) send your name and address plus $10 as carefully concealed cash or a check to: Bummers and Gummers Box 66 Yoncalla, OR 97499 Visit eco-forester Matthew Hall's A Forester Looks at the Healthy Forest Initiative Matthew Hall is an eco-forester using horses for logging when possible. He also is a teacher of ecological forestry at the Aprovecho Research Institute. Ms. Hall is the founder of the famous journal of country life, Bummers & Gummers. Lokiko Hall also writes fiction and poerty. Together, they often collaborate on projects, in the forest or writing about the forests. Also visit Lokiko Hall's stories at West By Northwest.org (and now "Bummers and Gummers" online at West By Northwest.org.) Let There Be Peace: An Interview with Two Teen Peacemakers Conversations with an Artist: Susan Applegate The Lay Of King Henry The Gypsy's Boy You may write to either Matthew or Lokiko Hall c/o publisher@westbynorthwest.org © Copyright 2000-2004 by West by Northwest.org |
