Treesearch

A climatic description of the Glacier-Waterton Lakes Park area; mainly covers Glacier. Contains numerous tables, graphs, and maps showing the year-round pattern of climatic elements and 10-day details during fire season. Data analysis includes frequency distributions in addition to average values. Examines relationship of averages to topography, weather correlations between stations, persistence of weather, and climatic trends during this century.

Differences between Prognosis Model versions 4.0 and 5.0 are described. Additions to version 5.0 include an event monitor that schedules activities contingent on stand characteristics, a regeneration establishment model that predicts the structure of the regeneration stand following treatment, and a COVER model that predicts shrub development and total canopy cover. Program performance has been enhanced by modifications to several of the submodels that predict tree increments.

Four treatments, all combinations of leaving or removing residual trees and shrubs or scarifying or not scarifying seedbeds, were evaluated for species differences in growth, vigor, and expression of dominance. Western larch was the dominant species in regeneration and growth but had begun to lose some of its advantage by age 25, particularly on scarified areas where overstocking commonly occurred. Douglas-fir was less sensitive to the treatments and, although significantly slower in absolute growth than larch, began to accelerate after 15 years of age. This study confirms that early...

Keys, brief descriptions, habitat data, and pertinent synonomy are provided for the vascular flora of the Desert Experimental Range to assist in range, wildlife, ecological, and other studies conducted on the area.

A vegetation classification based on concepts and methods developed by Daubenmire and refined by others were used to identify 16 forest habitat types on the Medicine Bow National Forest. Included were two habitat types in the Pinus flexilis series; three each in the Pinus ponderosa, Populus tremuloides, and Abies lasiocarpa series; and five in the Pinus contorta series. A key to identify the habitat types and the management implications associated with each are provided.

Engelmann spruce seed production and dispersal, and seedling establishment in the central Rocky Mountains indicate that in the Abies Iasiocarpa/Vaccinium scoparium habitat type, shaded, mechanically scarified, mineral soil seedbeds on north aspects can be adequately restocked naturally within a 5-year period in clearcut openings 300 to 450 feet wide. With shade or scarification alone, size of opening that will restock is reduced to 200 to 350 feet. The effective seeding distance is so limited on unshaded natural seedbeds on north aspects and on south aspects regardless of the seedbed...

Third in a series of proceedings of sYmposia on wildland shrubs, this publication brings together current knowledge of plants belonging to two important genera. Topics addressed by the 54 papers include distribution, systematics, genetics, revegetation and control, animal relationships, ecological relationships, entomology, pathology, and physiology.

This paper reviews the literature on factors affecting the yield and nutritional value of crested wheatgrass (Agropyron cristatum, A. desertorum or A. fragile). The Agropyrons are cool-season perennial bunch grasses that are grown in the western United States and Canada where annual precipitation ranges from 9 to 18 inches (230 to 460 mm) and forage yield ranges from 400 to 3000 pounds of dry matter per acre (450 to 3360 kg/ha). Forage production in the northern Great Plains is best correlated with April to June precipitation whereas in the area west of the Rocky Mountains production is...

Guidelines are provided to help the forest manager and silviculturist develop even- and/or uneven-aged cutting practices needed to convert old-growth spruce-fir forests into managed stands for a variety of resource needs. Guidelines consider stand conditions, succession, windfall risk, and insect and disease susceptibility. Cutting practices are designed to integrate timber production with increased water yield, maintained water quality, improved wildlife habitat, and enhanced opportunities for recreation and scenic viewing.

Two good, three heavy, and two bumper spruce seed crops were produced during a 15-year period. There was considerable variability in seed crops, however. Not all locations produced good to bumper seed crops when overall yearly ratings averaged good or better; conversely, some locations produced bumper seed crops in 3 or more years. Mathematical relationships, that should be useful in estimating potential sound seed production, were estimated between periodic annual15-year sound seed production and (1) periodic annual15-year total seed production and (2) selected stand parameters of...