Treesearch

Examines the d.b.h.-age and stockability relationships in aspen stands of varying ages and densities. Accounts for the curvilinear trend in the self-thinning relationship in young aspen stands.

Presents equations for estimating biomass of food available to beavers on five species of shrubs common to northeastern Minnesota.

The fifth Minnesota forest inventory found 16.7 million acres of forest land in 1990, of which 14.7 million acres is timberland. Growing-stock volume on timberland increased from 12.4 to 15.1 billion cubic feet between 1977 and 1990, a gain of 22%. Analysis and statistics on forest area, timber volume, growth, removals, mortality, and projections are presented.

This report includes the most commonly used Forest Inventory and Analysis statistics.

Proposes a framework for classifying and mapping aquatic systems at various scales using ecologically significant physical and biological criteria. Classification and mapping concepts follow tenets of hierarchical theory, pattern recognition, and driving variables. Criteria are provided for the hierarchical classification and mapping of aquatic ecological units of riverine, lacustrine, and ground-water systems within their geoclimatic and watershed settings. Some hydrogeomorphic criteria for classifying wetlands are also proposed.

Provides a summary of recommendations relating to the evaluation of the socioeconomic impacts of ecosystem management.

Presents the biology and ecology of the yellowheaded spruce sawfly, and provides survey techniques and management strategies. In addition, it provides information on identification, classification, host range, and the historical records of outbreaks in the Lake States.

Reports that low rates of sulfometuron, 70 grams per hactare (1 ounce product or 0.75 ounces active ingredient per acre), applied when hybrid poplars are completely dormant, can provide season-long weed control and increase hybrid poplar growth. If plantation access is not possible before growth activity begins in the spring, late fall application of this herbicide may be best.

Pulpwood production in the Lake States increased from 8.8 million cords in 1992 to 9.4 million cords in 1993. Michigan, Minnesota, and Wisconsin pulpwood production is shown by county and species group.

The latest Michigan forest inventory was completed in 1993 by the North Central Forest Experiment Station and the Michigan DNR, Forest Management Division. In total, 18,484 sample points were examined on aerial photographs to identify ground sample plots. Of these, 10,849 forest plots were visited and measured on the ground by field crews. These plot measurements included 357 thousand trees across the whole State, of which 226 were black walnut.