The 1948 seed crop was responsible for nearly all of the pine regeneration during 

 the 5-year study period at Bluesky, Warland, and Jackson. First-year results published 

 by Roe and Squillace (1950) showed that the number of pine seedlings was about eight 

 times greater on mineral soil (heavily scarified by bulldozer or on skid roads) than on 

 duff when other conditions were similar. These data were derived from 700 of the 730 

 milacre plots plus an additional 241 temporary plots located on cutover areas at Bristow 

 with larger numbers of seed trees. The number of pine seedlings per acre on mineral 

 soil increased from 830 to 6,000 as the basal area of the residual stands went from 17 

 to 87 square feet per acre. Also, the distribution of pine became more uniform as the 

 stand basal area increased. First-year stocking was satisfactory on mineral soil only 

 in stands with over 40 square feet of basal area per acre. If rodents were controlled, 

 stocking likely would have been adequate in stands with less basal area. Stands under 

 40 square feet of basal area ranged from 13 to 39 inches mean diameter and averaged 16 

 inches d.b.h. Stands over 40 square feet ranged from 16 to 33 inches mean diameter and 

 averaged 23 inches d.b.h. 



Initial survival of seedlings was far greater on heavily scarified seedbeds than 

 on any other surfaces and this approximate percent of difference existed throughout 

 the study period (fig. 4). By late June of 1949 more than five times as many pine 

 seedlings were growing on heavily scarified seedbeds (primarily skid roads) as on duff 

 at Bluesky, Jackson, and Warland (fig. 4); this is in contrast to nearly three times 

 more than on burned seedbeds and almost six times more than on lightly scarified sur- 

 faces. It is not known whether these differences resulted from greater germination 

 or less seedling mortality, or both, on the heavily scarified seedbeds. Mortality from 

 late June through mid-October 1949 was low on all seedbeds because of above average 

 rainfall from July through September. By early May of 1950 about half of the survivors 

 died on seedbeds prepared by light scarification or burning and about one-fourth died 

 on seedbeds prepared by heavy scarification or on duff. Frost heaving caused most of 

 the pine seedling losses on burned and scarified surfaces in the early spring of 1950. 



Five years after treatment, pine regeneration was still most abundant on the 

 heavily scarified seedbeds (fig. 4). These surfaces maintained nearly four times more 

 pine seedlings and three times greater stocking than on the other seedbeds. The numbers 

 of seedlings counted in July 1953, stated as percents of the 1949 seedling count are as 

 follows: 39 percent on burned seedbeds; 51 percent on untreated seedbeds; 55 percent on 

 heavily scarified (skid road) seedbeds; and 60 percent on lightly scarified seedbeds. 

 Most of the seedlings counted in July 1953 had germinated in May and June 1949. 



At Bluesky, Jackson, and Warland, most of the Douglas-fir seedlings were estab- 

 lished on all seedbeds prior to the beginning of the study. However, the only large in- 

 crease occurred on heavily scarified seedbeds in 1953 following the heavy 1952 seed crop. 

 All other seedbed treatments failed to enhance the initial survival of Douglas-fir. 



Seedling establishment of ponderosa pine at Dunn and Butler from 1952 to 1961 was 

 generally low, probably because of the lack of a receptive seedbed when seed was avail- 

 able. In addition, these plots were apparently established on the driest sites studied. 

 Although from 200 to 7,000 pine seedlings per acre were established by 1961 on the seed- 

 beds of both areas, poor seedling distribution resulted in an average of only 25 percent 

 stocking 10 years after treatment. More pine seedlings became established on bulldozer 

 scarified plots than on areas lightly scarified with an Athens disc or on duff. Addi- 

 tional pine seedlings became established at Dunn in 1954 and 1955 when the seed trees 

 were banded with aluminum strips to prevent squirrels from climbing the trees and when 

 the entire area was poisoned to decrease depredation by rodents. 



12 



