Treesearch

A planning model in which social, economic, and environmental constraints are specified--especially in mathematical form--can be helpful in decisionmaking. The general structure of a land-use decision model approached through systems analysis is described. The proposed procedures emphasize the quantification of interrelationships between uses and the specification of preferences and goals. The complexity of land-use planning is illustrated by an account of how the model might be applied on a Forest Service Ranger District of a National Forest in Colorado.

Thousands of acres of ohia lehua (Metrosidems collina) forests on the island of Hawaii have died, and tree death is progressing rapidly into healthy forests. Most of the losses are on State-owned lands. All of the "ohia decline" cannot be attributed to the same agent. Some of the earlier decline was attributed to frost and sulphur dioxide. But other factors, including possibly the shoestring root-rot (Armillaria mellea), are responsible for the current losses. Federal and State agencies are seeking to determine the causes of the decline and what control measures are feasible.

A case study on the Challenge Experimental Forest, California, demonstrated that logging along roadsides need not despoil roadside stands. Nearly every tree was "viewed" before marking. Because of the "special-care" procedures followed, combined logging and slash-disposal cost was about twice that of a single-tree selection cut.

Many tree species have been introduced into Hawaii from around the world (Bryan and Walker i962, Hillebrand 1965, St. John 1973). Trial introductions of new species for various forestry purposes began in the 19th century and are still continuing. Walker (1887), Judd (1915); Lyon (1929), Zschokke (1930), Bryan (1947), and Whitesell (1971, 1974), among others, have reported on some of the tree adaptability trials of government agencies and private organizations. But generally, adequate followup appraisals of the adaptability of species to the planting sites have not been performed, or at...

Enzymes in forest tree materials can be resolved by starch gel electrophoresis. A gel slab is prepared in a mold assembled from glass and plastic. Wicks containing an aqueous extract of macerated plant material are inserted in the gel and processed. The gel is sliced, stained, examined, and photographed. Isozyme bands produced by differential migration of enzymes indicate genetic segregation and recombination. This technique is familiar in other uses, but the procedure described here is specifically adapted to conifers.

Foresters in California were surveyed in 1970 to determine the extent of artificial regeneration and tree improvement efforts in the State. Seeding of Douglas-fir was the prevailing practice in the North Coast. Inland areas were being planted with conifers, including ponderosa, Jeffrey, Monterey, and sugar pines, Douglas-fir, and red and white firs. Manpower devoted to tree improvement programs amounted to 8.7 man-years. It was being used chiefly to select superior trees and to establish seed orchards of Douglas-fir and ponderosa and sugar pines. These tree improvement efforts fall far...

A low-cost projection-viewer has been developed to enlarge portions of microscale aerial photographs. These pictures can be used for interpretation or mapping, or for comparison with existing photographs, maps, and overlays to monitor environmental changes. The projection-viewer can enlarge from 2.5 to 20 times, and can be calibrated so that maps may be drawn with a minimum of distortion.

California black oak (Quercus kelloggii Newb.) is a potentially valuable species of wide distribution in California and southern Oregon. Site index curves related to slope aspect and to the site index of a close associate-ponderosa pine have been developed, and are reported for the first time in this Note. The curves should be useful in estimating the growth potential of California black oak in even-aged unmanaged stands of the Sierra Nevada and southern Cascade Range between 39' and 41' north latitude.

Four sets of standard site index curves based on statewide or regionwide averages were compared with data on natural growth from nine young stands of ponderosa pine in northern California. The curves tested were by Meyer; Dunning; Dunning and Reineke; and Arvanitis, Lindquist, and Palley. The effects of soils on height growth were also studied. Among the curves tested, those by Dunning and Reineke seem superior in describing height growth trends of dominant trees in the first 50 to 60 years of stand development. Forest managers can estimate site index more accurately by applying a set of...