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Harvesting. Introduction, Components, Work Elements, Planning January 10, 2002 James B. Hart. Why Harvest?. To satisfy public craving for wood products (demand side)--yearly harvest of roundwood in the U.S.
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Harvesting Introduction, Components, Work Elements, Planning January 10, 2002 James B. Hart
Why Harvest? • To satisfy public craving for wood products (demand side)--yearly harvest of roundwood in the U.S. • So land owners (sellers), loggers, milling and equipment manufacturing enterprises and their employees can make a buck (supply side) • To accomplish silvicultural & other objectives(ecological, hydrological, recreational, fish & game habitat) • To salvage timber killed or damaged by natural agents (fire, wind, disease, old age, ice damage, etc) • Clear land for development (agricultural, industrial, or residential-urban)
The Forester’s Perspective & Objectives of Harvesting • Forester’s perspective • The territory of the logging contractor or the logging engineer, but a forester must have significant knowledge of it to do his • Objectives of timber harvesting • production, from standing or naturally downed timber, of round logs or other useable elements • their transportation to the mill site • in such a way that • value of logged material is maximized • costs are minimized, • with due consideration given to environmental, legal and other constraints.
“HARVESTING --All work elements leading to the total preparation of a primary product” Secondary Products Primary Products Wood Elements Harvesting Wood Products Processing Trees, stump, logs, branches, tops, foliage, etc e.g. furniture e.g.lumber
Volumes of roundwood products harvested by region in US, 1991 (total of 17.9 billion cubic feet)
Distribution of hardwood and softwood product volume harvested in US, 1991 (percent of 17.9 billion cubic feet)
Distribution of roundwood product volume harvested in Michigan by species group, 1992 (percent of 391.1 million cubic feet)
“CLASSIC” LOGGING SYSTEM WORK ELEMENTS • FELLING • LIMBING • MEASURING & BUCKING • SKIDDING, YARDING • LOADING • TRANSPORTING • UNLOADING LIMBING LOADING
“EXPANDED” ELEMENTS(approximately chronological) • Planning--"Failing to plan is planning to fail”, or “6P’s - Proper Prior Planning Prevents Poor Performance” • Road design & construction--always a part of system, earlier or current • Felling, bunching?, bucking, limbing, --hand or completely mechanical (some may be done @ the landing) • Primary Transport -- (skidding or yarding or Forwarding)--move material to a landing • Transport--from the woods to the mill site (or may be an intermediate wood yard); road, rail or water • Unloading--in the wood and/or mill yard; highly mechanized • Storage--awaiting processing; most of the time
Choice of a Logging System and Equipment determined by many things: • Management and capital considerations • Volume per stem and per acre • Forwarding distance • Limbiness & defect • Underbrush • Terrain • Soils • Weather • Silvicultural considerations • Systems can be as simple as a single person with a chain saw, a tractor, and an old truck... to a highly mechanized (computerized) system
TYPES OF LOGGING SYSTEMS • Based on the piece length forwarded & equipment used • Short-wood (pulpwood) --trees delimbed & bucked into 4 ft. or 100 in logs • Long-log (veneer & saw logs) --trees delimbed and bucked into 8, 16, or 32 ft lengths (or any length in between) • Tree-length--trees limbed and topped at min. diameter limit • Whole-tree--limbing and bucking () done at landing • Total system components do not vary but the expression of them has many variations... • e.g. tree-length logs can be bucked into length at the landing or transported directly to the mill for merchandizing into the highest-value log package
Operation Planning and Scheduling • System components, whatever they may be, must be properly matched for effective performance in reaching objectives -- e.g. if the feller gets way ahead of the skidder, or if the loader cannot keep up with the skidder, etc., then the whole system is not optimized. • Planning is the first and most critical function performed in a logging business--it provides the discipline that weld together all parts of the harvesting system. • What is a plan? "A projected course of action which defines a necessary sequence of activities, identifies the techniques to be applied, and determines the timing requirements." • Planning must be done in the context of interfacing components and other system externalities.
AREA LAYOUT HAUL ROAD & CROSSING ANALYSIS SKIDROAD DESIGN & LAYOUT TURN-OUTS TURN-AROUNDS TRUCK SCHEDULING BOUNDARY MARKING HAUL ROAD PERMITTING CROSS ROAD PERMITING WETLAND, STREAM CROSSING PERMITS ROAD CONSTRUCTION CONTRACTING SAFETY TRAINING HARVEST HARVEST PLANNING ADMINISTRATION
Skid Trail and Roads Overview • Road location, layout, and construction concerns significantly influence the logging system & equipment used. • Most Michigan commercial forest areas already have a good network of secondary transport roads. building permanent truck haul roads is usually not a forester or logger responsibility weight and season restrictions may require permits • Woods road systems (primary transport) are often inadequate Forester frequently locate and may lay out skid roads and skid trails operation in wetlands and riparian areas may require permits steep slopes require special consideration • Culverts and bridges may require engineer design, lay out and construction. • Many roads on public lands are being closed—current rule-of-thumb the fewer roads the better (not always popular).
A Forester’s Harvesting Plan should include: • Management objectives—independent contractor (large or small) vs. company crew • Silvicultural factors—impose constraints and limitations • What treatment (e.g. a thinning vs. small clearcut vs. large clearcut)? • Are there seed bed requirements? Will site preparation treatments be used? • How about insects and diseases? • Physical site characteristics - including topography, soils, hydrology • mostly affects equipment limitations, erosion, timing, and safety • also pertains to road issues • Environmental, wildlife & aesthetic limitations • eg. Threatened & Endangered species, wetlands, old growth • more and more stringent, whether set by law or landowner / publics • “There is less and less place for careless harvesting.”
PRIMARY TRANSPORT SKIDDING YARDING
PRIMARY TRANSPORT (CONTINUED) FORWARDING
