Most southern pine timber is harvested b y independent logging contractors. Lesser amounts are harvested by logging crews employed directly by larger corporate wood-using organizations and by landowners themselves. Although the chances are that you will not harvest timber yourself, an understanding of what is involved in harvesting will better enable you to deal with prospective timber purchasers and work with the successful bidder for your timber. The logging methods used and the logger's ability to carry out your plans are critical to the overall success of forest management. Well planned harvests ultimately determine the financial success of the venture. The cash return immediately available from the harvest is dependent upon the logger producing the most valuable timber products possible. Site preparation and establishment costs of the succeeding stand are, to a large degree, dependent upon the completeness of harvesting. Future productivity of the site will depend on how well or how poorly the harvesting operations are carried out. Finally, harvesting operations will influence both the landowner's and the public's impression of the desirability of producing timber for profit. Harvesting includes as operations necessary to remove timber from the forest and deliver it to the mill. These operations are felling, limbing and bucking, skidding, loading, and hauling. Alternate methods for accomplishing each of these operations are available. The correct combination of methods to use on a given site depends on tract size, timber type, volume per acre, individual tree volume and see, type of cut (clearcut, thinning, etc.), terrain, weather, soils, road system, equipment availability, and landowner's desires. Before cutting begins, a harvesting plan should be developed for the entire tract. This plan will include: - the landowner's management objectives; - map of the area; - legal property boundaries; - description of trees to be removed; - method of marking trees to be removed; - method of harvesting; - the placement of haul roads, skid trails and log landings; - placement and types of stream crossings; - road and trail drainage structures; 1 - soil conservation measures, including Best Management Practices, to be used to protect water quality; - maximum height of stumps; - slash d isposal methods; - penalties for damaged fences, other man-made structures and residual trees. In addition, any other landowner or legal requirements should be incorporated into the plan. Next, a timber sale agreement or contract that incorporates the essential elements of the logging plan should be developed. It must be comprehensible, performable, and enforceable by both the landowners and logger: For example, if site preparation is to be the responsibility of the logging contractor, this should be a part of the contract and should stipulate the stocking level expected at termination of the contract. A landowner shod realize that each additional requirement is an expense to the contractor and will rest in a reduction of the stumpage price received. The following abbreviated descriptions of the harvesting operations normally used for southern pines will help the landowner understand the harvesting . process and assist when negotiating with a contractor. Felling Felling is the act of severing standing trees from their stumps. Felling is normally accomplished with a chain saw or a hydraulic-powered felling head mounted on a self-propelled machine. The chain saw is used for felling both sawtimber and pulpwood, and is the primary tool used for cutting higher-value products such as poles and sawlogs. (Figure 1) There are several types of felling heads available. Mainly used in cutting pulpwood, they have either one or two blades and shear the tree from the stump. They can cause damage to the butt log, thus limiting their use to pulpwood. Other heads use various methods to saw the tree, thereby reducing log damage. The felling head is mounted on a crawler tractor (Figure 2), rubber-tired crier (Figure 3), excavator (Figure 41, or specialized machine. Delimbing and Bucking This operation entails removing limbs from the trunk of the tree up to a minimum top diameter and cutting it into logs or bolts of predetermined lengths. Delimbing and bucking may take place where the tree is felled, or the entire tree may be skidded to a cleared area called a log landing for delimbing and bucking. Equipment used 2 includes chain saws or a variety of mechanized methods. In pulpwood operations, the entire tree (minus limbs) is often transported to the mill or concentration yard. In other pulpwood operations, the entire tree (limbs and all) may be reduced to chips at the log deck, with the chips blown into trailers for transport to the mill. Skidding In the South, most movement of wood from the stump to the landing is done with wheeled or tracked machines. Skidding, or dragging logs, is accomplished with rubber-tired skidders (Figures 5-6), crawler tractors (Figure 7), or even horses or mules. Skidders and crawlers can be equipped with wire nooses called chockers or grapples to secure the stems for transport. Forwarding or prehauling involves carrying the wood on a vehicle, from stump to landing. Skidder type machines, equipped with bunks or trailers (Figure 8) are commonly used. In mountainous areas, cable logging syste ms (Figure 9) are sometimes used. These have a tower, yarder, and cables to move the logs. Generally, there is less ground disturbance on steep slopes with cable yarding. Depending on sod properties, terrain slope and rainfall patterns, ground skidding can sometimes cause unacceptable levels of soil disturbance of forestland, resulting in reduced tree growth and lower water quality through erosion. These impacts can be reduced by a combination of minimizing the area in skid trails and logging in dry weather: The location of skid tab should be determined in the logging plan. They shod be located in the field before logging begins. Loading Loading is the ink between logging and hauling operations. Loading is performed from log deck located at the landing. Several landings are often used on larger tracts so that skidding distances are minimized. Loading is done with a variety of machinery, rarely by hand. The most common machines are hydraulic knuckleboom loader (Figure 10), front-end loader (Figure 11), and big-stick loader. If the end-product is wood chips, chippers are often located at the landing, and the chips are blown into special trailers. Hauling The final harvesting operation is the movement of belts, logs, trees, or chips from the deck to a local concentration yard or mull (Figure 12). All log decks should be located beside a haul road system developed for the tract. This transportation network, including deck and skid trail locations, shod be specified in the harvesting plan to minimize skidding distances, haul-road construction, maintenance costs, and soil and site disturbances. 3 4 These publications developed jointly by. Cooperative Extension Service USDA Forest Service Southern Region 5
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