Idaho Panhandle National Forest
Bonners Ferry, Idaho
The demonstration took place in a mixed conifer stand located near Bonners Ferry, Idaho. The stand was treated with conventional harvesting system (fellerbuncher). Scattered logging slash (tops and limbs) was bundled. Bundler was also used to bundle slash from piles. Approximately 40 to 60 tons per acre of slash was bundled. A local wood recycling (chipping) operator used the bundles for producing fuel (hog fuel) for wood to energy plants in the area.
The photos below display stands, slash piles to be treated, and operation of the slash bundler. Slash bundles were generated from both piles and scattered slash on the ground.
Pre-Bundling Operations (thinning & piling)
Scattered slash in a harvested mixed conifer stand.
Equipment piling logging slash.
Slash piles in a thinned mixed conifer stand.
A mixed conifer stand after the logging slash has been piled.
The John Deere 1490D in action, bundling slash.
The John Deere TJ1210 in action, bundling slash.
The John Deere 1490D in action, loading bundles on its bunk for forwarding.
The John Deere 1490D in action, forwarding bundles to the landing area.
The John Deere 1490D loading bundles on to a log truck.
A log truck loaded with bundles weighing in at the log yard scales.
The bundles being shredded for "wood-to-energy," or hog fuel.
Bonners Ferry RD Slash Bundler Test and Demo-Day Notes
June 23 through July 8, 2003
Synopsis of test and demo-day results from Barry Wynsma, the local coordinators' perspective:
Machine Test Issues and Preliminary Results
The following issues are a partial listing of what land managers and industry people need to discover during the slash bundler testing. My perspective on the preliminary results are:
Ground disturbance levels - Ground disturbance levels appear to be at acceptable levels for both the bundler and the forwarding of bundles activities combined. Research plots established by the Southern Research Station for determining disturbance levels before and after the test will disclose the actual disturbance levels at a later date.
Maneuverability in commercial thin treatment areas - After watching the bundler operate in the 40 acre commercially thinned unit for 11 days, the machine proved itself capable of operating in timber stands having residual leave tree spacing of around 20-30 feet with minimal damage to trees. It was noted that unbucked slash (i.e. pieces longer than 10 foot length) starts to create a maneuverability problem when the bundler attachment is turned perpendicular to the trails and the operator needs to move the machine along the trails.
Ability to leave required amounts of down woody material - The operator was skilled at operating the bundler but unfamiliar with the standard slash disposal contract provision that requires a range of large down woody material to be left scattered for nutrient cycling and other resource needs. This requirement was achieved to a level that would not have been acceptable for normal grapple piling contractors, mainly due to more fine material being left rather than larger material that would have been preferred. The machine itself is capable of achieving the desired results, given an operator that is well acquainted with brush piling contract specifications.
Terrain limitations - The bundler operated on slopes up to about 40% with little problem. The operator said that the machine could easily run on steeper ground. Upper limit was not determined at this test site. Side-hill limits were not tested. The machine moved straight up and down slopes with minimal tilting from side-to-side.
Production rates - Fuels treatment personnel who observed the operation thought that the production rate of the bundler was somewhat slower than typical grapple piling machines that can pile about 3-5 acres per day. Southern Research Station researchers conducted time/motion measurements and results will be published at a later date. I think that the production rate of the bundler could be increased if the slash is "prebunched" along skid trails, as is the practice in Finland. In fairness, the test site slash was not prepped with this technology in mind. If the bundler technology is used for future slash disposal on Forest Service timber sales/fuels reduction projects, project planners and operations personnel need to bear in mind that slash needs to be arranged during mechanical harvest operations to help maximize the bundling production rate. Tree spacing in commercially thinned stands affects the production rate to some degree, but I think slash arrangement is the main factor that affects bundling production rates as long as tree spacing is 20 feet or wider.
Biomass size limitations - Slash as large as about 10 inches in diameter (from post-harvest blowdown that was bucked up) were bundled, but the average size of the stems (not including branches) appeared to be around 3-4 inches.
Bundle length limitations - Bundles were cut at lengths ranging from 12 feet up to 16 feet. Bundle length affects maneuverability in commercial thin treatment areas. The longer the bundle, the more difficult it becomes to move the machine along skid trails without damaging residual trees. 14-foot bundles appeared to be the length best suited for this particular test site.
BTU levels in bundles (dry and green bundles) - Unknown until Forest Products Lab completes its research. One fuels purchaser from Avista Utilities cogeneration plant located at Kettle Falls, WA visually inspected a number of bundles at the test site and felt that the btu level would be relatively high and of high quality.
Transporting Bundles - Transporting bundles became a safety problem with the first mule-train log truckload of 29 bundles. The bundled material consisted of 4-year-old slash that I suspect weren't capable of being bundled as tightly as green slash may be. This created a situation where short pieces of loosely bundled material located at the ends fell out on the highway when being transported to the chipping facility approximately 15 miles away. All remaining bundles were transported using a dump truck that could carry 5-6 bundles safely contained in the dump box. Recommended solution to this safety issue would be to use hard-sided trailers for hauling bundles or perhaps forwarding bundles as far as 1-2 miles to sites near logging operations that are feasible to set up portable chippers and that are accessible to chip vans, so bundles are not transported on highways at all.
July 8th, 2003 Demo-Day Attendees
There were about 60-70 attendees during the public and media demonstration day held on July 8th, 2003. Approximately 40 additional people also made informal visits to the test site from the IPNF, Kootenai and Colville National Forests, Northern Region, timber and cogeneration industry people, Kootenai Tribe, local community leaders and curious passers-by during the two-week test period.
Telephone: (208) 267-6751
John Deere 1490D "Slash Bundler"