FERIC compared three harvesting systems (full-tree, tree-length, and cut-to length) on a clay site in northwestern Québec. None of the systems limited rutting to below the acceptable target level; however, cut-to-length harvesting (using a three-machine system) showed slightly better results than the other two systems.
In stands with small stems (<0.10 m³/stem), the two-machine cut-to-length harvesting system (a single-grip harvester paired with a forwarder) generally has low productivity. In this situation, a multi-stem head should be used to improve the system’s productivity. However, at high densities (>1800 stem/ha), even multi-stem heads may not be enough to make the two-machine system viable. This report identifies the conditions under which a three-machine system (a feller-buncher teamed with an at-the-stump processor and a forwarder) would be viable based on the results of four recent studies as well as on data from past FERIC studies. The report also discusses the productivity of processor operators as a function of their number of years of experience.
Cut-to-length systems based on a single-grip harvester and a forwarder are generally well suited to the protection of advance regeneration. However, regeneration levels may still sometimes fall below what is desired. In the first part of this study, FERIC investigated the factors that affect the survival of fir seedlings. Seedlings beneath piled wood sustained approximately twice as much damage as those located in the felling zone, whereas all seedlings located in extraction trails or under slash piles were deemed to be of unsatisfactory quality. In the second part of this study, FERIC proposed two variations on the usual work methods and studies the results in terms of protection of the regeneration. The method that concentrated slash and wood piles increased the level of protection afforded to the regeneration, without any major effect on harvesting costs. Dispersal of slash over the cutover did not provide satisfactory protection of regeneration, but might nonetheless improve a site's plantability.
Since July 2000, a contractor has been performing cut-to-length harvesting using a single machine: a modified shortwood forwarder that lets the operator switch rapidly between the forwarder's grapple and a single-grip harvester head. FERIC studied this combination machine working as a single-grip harvester and as a forwarder during the same week. The productivity was acceptable and the wood cost at roadside was comparable to that in a traditional system with two machines. The best use of this combination machine would be to complement the work of a conventional single-grip harvester.
Due to the scarcity of quality logs, the hardwood lumber manufacturing industry has been compelled to rely more and more heavily on lower grade or size logs, with a significant impact on the profitability of existing operations.
Tests conducted in a conventional sawmill equipped with a carriage and a resaw show that the conversion of 6 and 7-foot short logs entails losses of $85/Mbf for hard maple and $103/Mbf for white birch. An additional sample of below grade hard maple logs, 8 feet and over in lengths, selected from previous studies, led to even more severe losses of $121/Mbf. Only the better quality below grade logs and those in diameter classes over 30 cm generated profits; unfortunately, such diameters represent only a very small percentage of the available resource.
According to our simulations, a conventional mill cutting about 500 sawlogs per shift could include up to 70% hard maple short logs in its regular production before getting into a loss situation. If the same mill used short or below grade logs exclusively, it would have to process over 900 short logs or 725 below grade logs to reach the breakeven point. To generate a 10% profit, it would have to process some 1100 short logs or 900 below grade logs.
Such productivity levels are only achievable with more linear manufacturing processes. Our simulations showed that the addition of a second production line equipped with an end-dogging carriage system to process 1300 hard maple short logs per shift would barely cover costs, profits being in the order of $9/Mbf, i.e. $181,000/year. The drastic escalation of production costs due to the second line limits the effect of greater productivity on the expected profitability of the mill. The second line would need to process 1800 maple short logs per shift for the mill to achieve 10% profits, i.e. $71/Mbf or $1.8 million/year. This level of productivity can be obtained with twin saws fed with a sharp chain rather then an end-dogging carriage system.
Hardwood lumber producers should consider producing lumber that meets specific client requirements rather than simply meeting NHLA rules. Just by grading our lower grade boards on their better face to recover a certain percentage of clear cuttings instead of applying NHLA rules, we increased the value of our maple and birch products by $26/Mbf and $18/Mbf respectively with negligible impact on volume.
Significantly greater gains are achievable. If the whole production was graded to NHLA rules on its better face, it would be possible to generate 31% more #1 Common & Better maple and 46% more #1 Common & Better birch. In addition, the percentage of sapwood boards would increase by 5% with both species.
FERIC studied fully mechanized cut-to-length systems during commercial thinning treatments in white spruce plantations and natural black spruce stands. The equipment's performance was assessed to better understand the effects of various organizational factors on productivity. The productivity of single-grip harvesters was little affected by variations in the trail layout and removal intensity, and by different sorting strategies. Shortwood forwarders benefited from situations in which large volumes were available for extraction on each trail. As well, it appears that precleaning treatments are not economically justifiable.
In the fall of 1992, FERIC conducted a survey of the forest industry in British Columbia and Alberta to determine future trends in log-hauling practices. This report summarizes and interprets the results of the survey, reviews new developments in log transportation technology, and develops load centre of gravity positions for different tractor/trailer configurations.
Transport of dry mountain pine beetle–killed wood may result in hauling inefficiencies because the lower weight density of this wood may not allow maximum truck axle weights to be achieved. The Forest Engineering Research Institute of Canada (FERIC) conducted a project to determine if seven- and eight-axle cut-to-length log hauling configurations are able to reach maximum axle weights when hauling dry beetle-killed wood. FERIC calculated the increase in per-tonne-hour hauling costs to the mill and to the log hauling contractor as a result of hauling underweight loads, and investigated options to increase the load carrying envelope with the use of wider bunks and higher loads. FERIC also conducted a loading trial to determine if a fourth bundle of 5.0 m logs can be added onto B-train configurations.
The Forest Engineering Research Institute of Canada (FERIC) studied mechanized processing in cable yarding operations in summer conditions in northern British Columbia. Two danglehead processors were monitored in seven cutblocks to determine processing productivity and costs, the amount and cost of loader support required, and the effects of slope and other factors on productivity.