. Natural reforestation on a mile-square clearcut in southeast Alaska / by Harris. Forest regeneration Alaska; Cutover lands Alaska. CEDAR 3 ^ 5 3 6 SPRUCE 25 21 27 \ 41 / 74 \ HEMLOCK 72 70 \ 53 1955 1958 1960 1962 Figure 12.—Species composition in percent—seedlings at least I year old. Mile-square cutting unit, Maybeso Experimental Forest. Hemlock seedlings were not only more num- erous than spruce or cedar, but also tended to be larger. In 1962, a hemlock was the largest seedling present on 57 percent of 4-milacre plots examined, a spruce on 40 percent, and a cedar on 3 percent. Domina
. Natural reforestation on a mile-square clearcut in southeast Alaska / by Harris. Forest regeneration Alaska; Cutover lands Alaska. CEDAR 3 ^ 5 3 6 SPRUCE 25 21 27 \ 41 / 74 \ HEMLOCK 72 70 \ 53 1955 1958 1960 1962 Figure 12.—Species composition in percent—seedlings at least I year old. Mile-square cutting unit, Maybeso Experimental Forest. Hemlock seedlings were not only more num- erous than spruce or cedar, but also tended to be larger. In 1962, a hemlock was the largest seedling present on 57 percent of 4-milacre plots examined, a spruce on 40 percent, and a cedar on 3 percent. Dominant hemlock seed- lings averaged 5 feet in height with a maximum of 11 feet, dominant spruce seedlings averaged 2 feet in height with a maximum of 5 feet, and dominant cedar averaged 2 feet in height with a maximum of 3 feet. Hemlock seedlings were larger because more were advanced seedlings, well established before logging, that survived to become the dominant early stand compo- nent. How far the present trend in species com- position toward more spruce will continue is uncertain now. Taylor (1934) found that sec- ond-growth stands in southeast Alaska usually contained from 10 to 75 percent spruce by basal area, depending on soil type and stand age, and estimated that, on the average, the proportion of spruce in second-growth stands at the end of a rotation period of 75 to 100 years will be about 50 percent. DESCRIPTION OF NONSTOCKED PLOTS In 1962, ninety-nine 1-milacre plots, or 31 percent of the total examined were not stocked with coniferous seedlings (fig. 13). Disturbed soil was the most common surface condition on nonstocked plots. Soil movement on all but one plot was the result of landslides. Figure 13.—One-milacre nonstocked plots by percentage ot ground cover or surface condition, 1962. Mile-square cutting unit, May- beso Experimental Forest. or debris flows occurring after 1958. Slides are common on steep, forested slopes throughout southeast Alaska, but their
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