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Rhizopogon is a large genus mycorrhizal fung of particular importance to the Pinaceae. Rhizopogon species occur in both young and old forests, in diverse habitats and are present on every continent but Antarctica. Ths ecological amplitude was recognized early in the 20th century when Rhizopogon species were observed as dominant ectomycorrhizal fungi in exotic pine plantations. Establishing Rhizopogon in nursery inoculations at international nurseries has greatly benefited the establishment of North American conifer species around the world.

Afforestation and reforestation in Israel are done on marginal lands, which consist of poor and shallow soils, with precipitation ranging from 650 mm in the north down to 200 mm in the south. Therefore, seedling quality is of great concern. All forest seedlings planted in Israel are produced by three forest nurseries which belong to the Forest Authority of Israel. About 3 million seedlings of about 30 species are produced each year (of which are conifers).

The forest economy in Chile is based on products from artificial reforestation efforts on approximately 2 million ha. From these, about 1.5 million ha (75%) are planted with Pinus radiata, 400,000 ha (20%) with species of Eucalyptus, principally E. globulus and E. nitens, and the rest (5%) composed by other species such as Pseudotsuga menziesii, Pinus ponderosa, Pinus contorta, and some hybrids of the genus Populus. Annual planting rates have varied from a maximum of 130,000 ha in 1992 to approximately 28,000 ha in 1999. This year (2000), the planting period is unfinished but is estimated...

Forestry programs in the American-affiliated islands of Micronesia and American Samoa are relatively young, compared to those of mainland states. American Samoa and Guam have been American Flag Territories since 1899, but neither had a forestry program before 1970. American Samoa had no forestry program until 1987. After World War II, the United States was the de facta government in the Northern Marianas, Marshalls, and Eastern and Western Caroline Islands, many of which had been devastated by the battles. The United Nations made these islands "Trust Territories of the United States" under...

Diesel fuel oil was applied to mountain pine beetle (Dendroctonus ponderosae Hopkins) infested bolts of ponderosa pine (Pinus ponderosa Lawson) in early June. Just prior to the fuel oil application and 6 weeks later, 0.5 ft2 bark samples were removed from each bolt and the numbers of live beetles counted. Beetle survival was 8.3% in bolts arranged in a single layer and 4.8% in bolts arranged in 2 layers.

Mistletoes of the families Loranthaceae and Viscaceae are the most important vascular plant parasites of conifers in Canada, the United States, and Mexico. Species of the genera Psittacanthus, Phoradendron, and Arceuthobium cause the greatest economic and ecological impacts. These shrubby, aerial parasites produce either showy or cryptic flowers; they are dispersed by birds or explosive fruits. Mistletoes are obligate parasites, dependent on their host for water, nutrients, and some or most of their carbohydrates. Pathogenic effects on the host include deformation of the infected stem,...

The Forest Vegetation Simulator (FVS) is a computer program that projects the development of forest stands in the United States and British Columbia, Canada. The proceedings of the second FVS conference, held in Fort Collins, CO, includes 34 papers dealing with applications of FVS that range from the stand-level through full-scale landscape analyses. Forecasts ranging from wildlife habitat indicators through economic returns on investments take into account the effects of insects, pathogens, and fire. Also presented are recent advances in computer visualization technology, the analysis of...

Although there are numerous sources for information on the practice of silviculture (Forest Service 2002), special considerations are required for control of dwarf mistletoe (Scharpf and Parmeter 1978). Mistletoe-infested forests, stands, and trees develop and respond to treatment differently than their uninfested counterparts (chapter 5). The spread, intensification, damage, and impacts of dwarf mistletoe can be reduced, maintained, or enhanced by silvicultural treatments alone or in combination with other control techniques (chapter 7).

The opportunity and need for management of mistletoe populations with biological, chemical, and genetic approaches are greatest for application to the dwarf mistletoes. Although much information is available on these management strategies (see reviews by Hawksworth 1972, Knutson 1978), significant research and development are still required for these to become operational tools. In this chapter, we describe the potential for these tools and status of their research and development. Resource managers and practitioners interested in using these approaches can consult with forest pathologists...

Dwarf mistletoe surveys are conducted for a variety of vegetation management objectives. Various survey and sampling techniques are used either at a broad, landscape scale in forest planning or program review, or at an individual, stand, site level for specific project implementation. Standard and special surveys provide data to map mistletoe distributions and quantify disease severity. At a landscape scale, extensive surveys assess regional impacts, estimate mistletoe occurrence, intensity, and effects, and estimate future growth and yield. Intensive surveys evaluate stands, campgrounds,...