Three conifer species were planted and compared on a large clearcut in central Idaho. Three scalp sizes were also compared. The study site is harsh and has a history of plantation failures due at least in part to a heavy coverage of elk sedge (Carex geyeri F. Boott).Fifth-year results indicate that lodgepole pine (Pinus contorta var. latifolia Engelm.) had the best survival and height growth. Ponderosa pine (Pinus ponderosa Dougl. ex Laws.) was intermediate, while Douglas-fir {Pseudotsuga menziesii var. glauca [Beissn.] Franco)showed the poorest performance. On 2-ft (0.6-m) handmade scalps, tree survival was lower and total height was less than on 4-ft (2.4-m) wide dozer strips. This was especially true for the pines.It appears that on hot and dry sites where elk sedge or other grasses are extremely competitive, 4-ft scalps are the minimum site preparation required. Adequate site preparation along with matching of proper species to the site conditions as well as adequate control of livestock and gophers can help ensure success in reforesting these sites.

fiud break tests were conducted at Lucky Peak Nursery following six different lift dates from September to April. On the average, lodgepole pine seedlings consistently broke bud before ponderosa pine seedlings. For both species, bud break began sooner, accelerated faster, and was more complete with each successive lift. Fertilizer treatments did not affect time to bud break. Seedling moisture regime and soil texture, however, affected bud break differently for the two species. Daily temperatures and bud burst data were used to determine optimum lifting times.Conifers of temperate climates are exposed to cool temperatures in the fall, which causes them to undergo physiological changes. These internal changes allow the trees to withstand the low temperatures of winter and to break dormancy and resume growth when environmental conditions become more favorable. The chilling requirements of several conifers have been studied: Abies procera Rehd. (Tung and others 1986); Picea abies (L.) Karst. (Dormling and others 1968; Worrall and Mergen 1967); Pinus contorta Dougl. (Ritchie and others 1985); Pinus monticola (Dougl. ex D. Don.) (Steinhoff and Hoff 1972); Pseudotsuga menziesii (Mirb.) Franco (Campbell and Sugano 1975; Ritchie and others 1985) and that dormancy is composed of three main parts. The first and third are periods of quiescence when seedlings can be induced to grow in a favorable environment. Kramer and Kozlowski (1979) also refer to these reversible periods of inactivity (quiescence) as predormancy and postdormancy. In

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Eight fertilizer treatments combined with three irrigation regimes were used when growing lodgepole and ponderosa pine seedlings on two soil types at Lucky Peak Nursery near Boise, ID. Seedlings of both species were larger on the sandy loam than the clay loam soil. Milorganite, an organic fertilizer derived from sewage sludge, reduced initial seedbed densities but had no further effects. Ammonium nitrate increased seedling size on the clay loam, but not on the sandy loam soil. Increased irrigation was more effective in increasing seedling size on the sandy loam than on the clay loam soil. However, ponderosa pine receiving the least irrigation in the nursery grew the fastest for 3 years after being transplanted in the field, possibly because of drought conditioning.

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