Silvicultural treatments

Silvicultural Treatments. Preventive silviculture should be practiced (16) to promote individual tree resistance to bark beetle attack by (1) favoring the most resistant species ... 

An IPM program undertaken around Dillon, Colorado, in 1982, exemplifies the combination of treatments used to manage a mountain pine beetle outbreak in lodgepole pine. Direct suppression and preventive spraying were important to the Dillon project because of the high recreational values. But these activities were only intended to limit immediate tree losses and allow time to implement cultural or silvicultural treatments. 

Sutton (1984) emphasises two general silvicultural principles that no aspect of silviculture can be considered in isolation , and that for any silvicultural practice both yield and tree quality are largely predictable . To which he added that tree quality is very largely determined by the early silvicultural treatments , e.g. late pruning is a waste of time as the pruned envelope will be too narrow to provide much clearwood. The principal practices controlling wood properties are summarised in Table 5.5. 

Wilkins, A.P. Stamp, C.M. Relationship Between Wood Color, Silvicultural Treatment and Rate of Growth in Eucalyptus Grandis Hill (Maiden). Wood Science and Technology 24 1990, pp. 297-304. 

Natural regeneration of western larch can be successful provided a reliable seed source, a suitable seedbed, and adequate bght are available. Western larch seed disperses up to 240 m from seed trees at the forest margin into open areas (Shearer, 1959). If bare soil is exposed near a seed source, overstocking can result. Dispersal is less uniform in clearcuts than in seed tree and shelterwood silvicultural treatments (Schmidt and Shearer, 1990). Rodent and bird predation reduce seed germination significantly (Stoehr, 2000). 

A review of silvicultural systems for Picea sitchensis in the UK (Macdonald and Hubert, 2002) provides further examples of product push with low valued pallets, packaging and fencing absorbing two-thirds of production - and Sitka spmee is classified as non-durable and resistant to treatment. 

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