ENVIRONMENTAL CONSEQUENCES in rocky mountain coniferous ...

Gentle slopes and easy access to cutting units made possible the use of ground
skidding harvesting systems. All units were logged using crawler tractors to accom-
pl ish skidding. On areas designated for intensive uti 1 ization, smaller trees (1 " to
6" in diameter) (2.5 to 15 cm) were bunched by hand prior to skidding, and were
skidded tree-1 ength. Units designated for broadcast burning were burned the season
following harvesting.
The Teton Study Site
The Teton study site is located on the Gros Ventre District, Bridger-Teton
National Forest, southwest of Dubois, Wyo. The site is typical of higher elevation
old-growth lodgepole pine in the central and northern Rocky Mountains. The area is
a gently rolling plateau at about 9,000 feet (2,743 m) elevation, in the Abies
Zasiocarpa/Vaccin~um scopariwn habitat type. The stands are essentially pure, overmature
lodgepole pine, interspersed with natural open meadows. Stand volumes are
heavy for lodgepole pine, averaging in excess of 9,000 ft3 per acre (254 m3) in
stems 3 inches (7.6 cm) d.b.h. and larger. As a result of endemic insect activity,
mistletoe, and other causes of mortality, standing and down dead material makes up
approximately one-third of this volume.
Management objectives for old-growth lodgepole pine sites include
--timely regeneration and development of a new stand;
--avoiding or reducing possible insect and disease impacts,
both on adjacent stands and the new stand;
--protecting or enhancing esthetic and wildlife habitat
val ues ;
--Avoiding adverse biological impacts on site qua1 i ty.
Historically, the lodgepole pine timber type has been considered most important for
wildlife habitat, high elevation watersheds, and other such non-timber uses. More
recently, however, the emphasis has shifted to recovery of available wood to meet a
growing demand for softwood products.
Harvesting activity in old-growth lodgepole pine often results in large volumes
of residue because of the decadent nature of the stands. Consequently, harvesting
alternatives that can achieve more intensive recovery and utilization of the total
fiber resource are particularly important to successful management of the site.
Intensive utilization can solve a difficult residue disposal- problem, reduce adverse
public reaction to harvesting, and facilitate planting and other site-management
activities. The ultimate value of intensive utilization as a management tool,
however, depends upon the aggregate influence upon nutrient availability, microclimate,
beneficial soil microorganisms, soil moisture, and other site quality factors.
Si 1 vicul tural a1 ternati ves in 01 d-growth lodgepole pine are generally 1 imi ted to
clearcutting in some fashion, since a manageable residual stand does not exist.
Treatments applied to the study site specified clearcutting, and included two levels
of utilization and four post-harvest site treatment alternatives (table 3).
The inten-
si ve or "near complete'' uti 1 i zation treatment was intended to eval uate a harvesting
alternative in which virtually all wood fiber on the site is used, either as sawlog
material or as chips for pulp or particleboard. In the absence of a chip market, the
possibility of chipping residue and returning it to the site (in lieu of other dispos-
al methods) still exists. Spreading chips back on the site, one of the specified Post-
harvest treatments, al lows evaluation of the biological consequences of this option.