Clear cutting with Natural Reproduction A species' silvical characteristics are decisive in the choice of this method. If open situations are favored or re- quired for successful establishment of a species in nature, as exemplified by stand histories, then clearcutting may warrant consideration. The extreme open ituations created by clearcutting rarely occur in nature. The closest approxima is a fire-killed stand. But here, although root competition is removed, the tion dead trees cast considerable shade and erosion hazards are less. Assuming regen eration is favored by clearcutting, the width of the cut area depends on the dis semination characteristics of the seed that comes from the edge trees. Where species such as jack and lodge pole pine have serotinous cones which remain closed on the trees for many years, the slash after harvesting contains abundant seed which is released after ground temperature or light fire opens the cones In this case, the width of the cut has no limit from the standpoint of ensuring regeneration. Tree seed that may be stored in the litter for more than a year by a few species is too unreliable to depend on for regeneration. On the contrary, very large numbers of seed from brush species such as Ceanothus and Ribes in the West remain viable for up to 100 years in the forest litter layer. The presence of long-lived seed of brush species can therefore strongly influence the rate of invasion and competition for seedlings and may deter the choice of clearcutting and prescribed burning
Clear cutting with Natural Reproduction A species' silvical characteristics are decisive in the choice of this method. If open situations are favored or re- quired for successful establishment of a species in nature, as exemplified by stand histories, then clearcutting may warrant consideration. The extreme open ituations created by clearcutting rarely occur in nature. The closest approxima is a fire-killed stand. But here, although root competition is removed, the tion dead trees cast considerable shade and erosion hazards are less. Assuming regen eration is favored by clearcutting, the width of the cut area depends on the dis semination characteristics of the seed that comes from the edge trees. Where species such as jack and lodge pole pine have serotinous cones which remain closed on the trees for many years, the slash after harvesting contains abundant seed which is released after ground temperature or light fire opens the cones In this case, the width of the cut has no limit from the standpoint of ensuring regeneration. Tree seed that may be stored in the litter for more than a year by a few species is too unreliable to depend on for regeneration. On the contrary, very large numbers of seed from brush species such as Ceanothus and Ribes in the West remain viable for up to 100 years in the forest litter layer. The presence of long-lived seed of brush species can therefore strongly influence the rate of invasion and competition for seedlings and may deter the choice of clearcutting and prescribed burning
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