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Rehabilitation of skid trails, temporary roads, and log landings is required for many harvested sites in British Columbia; however, more information is needed regarding practical methods to return these access areas to productive forest. Lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) seedlings (1 + 0) were planted into (i) fully rehabilitated landings (burn-pile debris and topsoil incorporated), (ii) tilled landings, and (iii) unprepared portions of the adjacent cutblock. After two seasons of growth in the field, seedlings planted on fully rehabilitated landings were 38% larger, more robust, and exhibited 44% greater absolute growth and 22% greater relative growth rates, than seedlings planted in the adjacent cutblock. Seedlings planted on tilled landings were 33% smaller, and exhibited absolute growth rates 38% less, and relative growth rates 18% less, than seedlings planted in the adjacent cutblock. Seedlings planted in the cutblock exhibited higher ectomycorrhizal colonization rates. Our results indicate that tillage alone was not sufficient to fully rehabilitate these landings, but that incorporation of recovered topsoil and burn-pile debris produced an excellent growth substrate. This method, using materials found on site, can prevent a significant loss of land regenerating to productive second-growth forest. En Colombie-Britannique, les sentiers de débardage, les chemins temporaires et les jetées doivent être réhabilités dans plusieurs stations après une coupe. Cependant, il faudrait plus d’informations sur les méthodes pratiques pour remettre en production ces zones d’accès. Des semis de pin tordu latifolié (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) (1 + 0) ont été plantés sur (i) des jetées complètement réhabilitées (débris provenant d’empilements brûlés et incorporation de sol arable), (ii) des jetées labourées et (iii) des portions adjacentes du bloc de coupe non préparées. Après deux saisons de croissance au champ, les semis plantés sur les jetés complètement réhabilitées étaient 38 % plus gros, plus robustes et avaient une croissance absolue 44 % plus grande et un taux de croissance relative 22 % plus élevé que les semis plantés dans le bloc de coupe adjacent. Les semis plantés sur les jetées labourées étaient 33 % plus petits et avaient un taux de croissance absolue 38 % inférieur et un taux de croissance relative 18 % inférieur aux semis plantés dans le bloc de coupe adjacent. Les semis plantés dans le bloc de coupe adjacent avaient un taux de colonisation ectomycorhizienne plus élevé. Nos résultats indiquent que le travail du sol seul n’est pas suffisant pour complètement réhabiliter ces jetées mais que l’incorporation de sol arable récupéré et de débris provenant d’empilements brûlés a produit un excellent substrat de croissance. Cette méthode, qui a recours à des matériaux trouvés sur place, peut prévenir d’importantes pertes de terrains qui, en se régénérant, supporteront une forêt de seconde venue productive. [ABSTRACT FROM AUTHOR]

A two-year field trial was conducted to determine the growth response, and root emergence pattern of interior lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) seedlings in response to container type and forest floor removal. Seedlings were grown in Styroblocks™, Copperblocks™, or AirBlocks™, and were planted directly into the undisturbed forest floor or into manually prepared planting spots where the forest floor had been scraped away to expose the mineral soil. Seedlings planted into scalped planting spots exhibited marginally but significantly (7%) greater above-ground growth rates (seedling stem volume); whereas seedlings planted into the forest floor produced significantly more (11%) new roots. There were no differences in above- or below-ground biomass. Seedlings grown in Copperblock™ containers produced a higher proportion of roots near the top of the plug when tested at lifting, however this pattern was not observed in the field. Given that scalping is more costly than forest floor planting, and that the increased shoot growth was relatively small, we recommend that forest floor planting be considered as an alternative to manual spot scalping for sites, such as the site tested here: those with cold, but well-drained soils and where competition from other plants is not a serious problem. [ABSTRACT FROM AUTHOR]