Shortwood Systems. NSCC-Natural Resources Forestry

Transcription

1 NSCC-Natural Resources Forestry

2 Shortwood harvesting systems produce products at the stump Wood is piled (bunched) in the woods on cutting trails Products include pulpwood, studwood, sawlogs, fence posts etc.

3 Trail cutting or Strip cutting Work strips laid out with center line ribbon or both sides ribboned Always keep sides of trail clean, where wood will be piled Fall trees towards center of strip which places removed limbs and tops on forwarder trail

4 Remove all under brush (suppressed trees, small unmerchantable trees, etc) while you are cutting. Not afterwards Stumps must be kept low (high stumps restrict forwarder travel and also contain a large volume that is lost if stumps are to high. One foot of stump contains the same amount of wood as the last 8 ft length of tree)

5 With small trees, before limbing the tree, throw or roll the butt end close to the piles. This saves steps when bunching As you limb the tree, measure the bolt lengths and mark the cutting points with the saw. Mark both top and bottom Start cutting at the trail center and move towards the sides of the trail

6 BUNCHING WOOD Make bunches along both sides of the trail Leave forwarding road at least 14 ft wide Sort products in separate piles Make bunches big enough for at least a grapple load. (0.15 cords) Small piles eliminates long carrying distances

7 Bunches must be neatly piled at each end. This gives the cutter a better scale which increases pay Keep bunches in straight line along cutting trail Mark each pile with lumber crayon (cutters initials and type of product. WL-S, WL-14, WL-P, etc.)

8 PLANNING Organize your cutting strip Foot trail wood zone slash zone wood zone foot trail 1.5 m 3.0 m 6.0 m 3.0 m 1.5 m Walking Bunching Forwarding Bunching Walking

9 Quality Control Pulpwood usually two grades, premium, grade 1, or greenwood and standard, grade 2, or dry wood. Studwood (usually has a minimum diameter and usually 6 in trim allowance) Sawlogs (lengths vary from buyer to buyer but all need 4-6 inch trim allowance)

10 All roundwood products have delivery dates according to season For example, at Storaenso freshly cut in April-Delivered within 4 weeks May1-Sept 30-Delivered within 3 weeks October-Delivered within 4 weeks Nov 1-March 31-Delivered by April 30 Note: Shipping dates are strict. Failure to meet dates results in lost revenue because of reduced price or total load rejection

11 NR-F Specs Premium Pulpwood (grade 1) Balsam Fir and Spruce only Dimensions: L-1.80 to 2.60 m. Must not exceed 2.60 m. Both ends sawn at right angles to log axis with scarf removed Diameter-minimum 11.5 cm inside bark, no maximum limit

12 Technical specs All bolts must be straight All limbs removed cleanly and all knots trimmed flush with bolt surface Excessive knots are not accepted Sweep must not exceed 5 cm over the length of the bolt

13 Standard Pulpwood (grade 2) Spruce and balsam fir Pine and hemlock must be separated by species Tamarack/larch not accepted Delivery dates: May-October-2 months

14 Standard grade Length: 1.80 m up to 2.60 m with both ends sawn at right angles to log axis with scarf removed Diameter: minimum 9 cm inside bark. Fresh green spruce may have an inside bark diameter of 7 cm

15 Standard grade technical specs All bolts must be reasonably straight without sharp crooks and all limbs trimmed flush with the bolt surface. Sweep must not exceed 30 cm

16 Standard grade quality specs Volume of pine and hemlock controlled by the buyer Maximum of 7% of total Standard grade deliveries Loads containing charred, burnt or hardwood will be rejected No sap rot, stain acceptable if annual rings are clearly visible

17 Standard grade quality specs A load may contain up to 10% bright, dry wood Heart rot and holes: Dia. Less than 13 cm- no rot Dia cm- max. one third dia. Dia. Over 20 cm- max. one half dia Decayed wood in a load will be accepted provided that the cull stick volume plus the actual rot volume does not exceed 3.5% total load

18 Defects-rot deductions will be made to grade specs described Stain will not considered a defect If annual rings are clearly visible on end surface the bolt is considered acceptable and no deduction made

19 Defects-other Buyer retains the right to make deductions for crooks and other deformities which limit the usefulness of the bolt Void is an unnecessary airspace large enough to accommodate the average sized bolt in the stack or load

20 Crooked bolts Sweep must not exceed 5 cm in Premium grade Sweep must not exceed 30 cm in standard grade Faulty wood Includes scars, heavy knots, poor limbing (stubs) and other deformities which hinder the debarker from doing an acceptable job are considered culls

21 Burnt wood: any load containing burnt wood will be completely rejected Hardwood bolts not accepted in a load and when present will be culled and supplier notified Undersized- 1 bolt per 2m 3 (stacked) Poor quality wood will be reported and supplier notified once only. Thereafter wood shall be refused

22 Extraction methods Shortwood system harvesting requires carriers to extract product from the woods and deliver it roadside Machines common to shortwood systems include: Forwarders (tree farmers) Tractors with trailers (some may be powered) Horses with sleds and/or sleighs

23 Longwood Systems Longwood harvesting systems include: Tree length- tree is felled and limbed in the woods and moved roadside or to the mill for processing Full tree- tree is felled and move roadside for processing with branches still on

24 Longwood Systems Tree length Common extraction methods are: Skidders (both grapple and cable) Clam bunks Horses Tractors with winch

25 Longwood Systems Processing: tree length system Roadside processing can include: Slashers Chippers Chainsaw (manual) Note: Tree length harvested products are usually shipped to the mill and processed there. They are scaled by weight.

26 Longwood Systems Full Tree Harvesting System Trees are felled and moved roadside for processing Roadside processing can include: De-limbers Slashers Chippers

27 Longwood Systems Common equipment used in full tree harvesting systems are: Feller bunchers Grapple skidders Cable skidders (small operations usually fuelwood) De-limbers Slashers Processors

28 Longwood Systems Note: Full tree harvesting is not widely used Slash and debris is removed from forest floor. This results in lost nutrients that would otherwise be left in the forest to help build soil structure

29 Mechanized Systems Note: Mechanized forestry has been greatly increased in Canada due to advances in technology Equipment common to mechanized operations include: Feller bunchers Grapple and cable skidders Slashers Processors (single and double grip)

30 Longwood Systems Feller Bunchers- harvest trees in bunches that are then laid down in rows for extraction Grapple skidders- wood must be in bunches that are moved roadside Cable skidders- cables are equipped with chokers that are placed on one or more trees and skidded roadside

31 Longwood Systems Slashers- can be best described as a type of mobile sawmill that cuts trees into common lengths. (sawlogs, studwood, pulpwood, etc.) Chippers- chip whole tree (hogfuel) and tree lengths (chips) either at roadside (common) or at the mill