Summary:
Published in Forest Ecology and Management 94: 219-231
A study comparing two scarification intensities (single and double passes) was established 3 years after harvesting a black spruce-mosses stand using the group seed-tree method. The effects on black spruce (Picea mariana (Mill.) B.S.P.) advance growth, natural seedling establishment and competing vegetation were examined in relation to seedbed changes over a 5-year period. Scarification was effective in controlling ericaceous shrubs and it greatly changed seedbed types. It removed 50-75% of the feather moss coverage, the effect being related to intensity of treatment. The F horizon was the dominant seedbed produced by scarification which also exposed underlying layers more favorable for seed germination. After 5 years, the two scarification intensities improved black spruce stocking from natural seeding (40-47%) compared with clearcut only (32%). Stocking decreased linearly with distance from seed-tree groups which appeared to be efficient up to 50 m only. Scarification greatly increased paper birch (Betula papyrifera (March.)) regeneration proportionally to intensity; the number of seedlings was doubled by the single pass (6333 ha-1) and more than tripled by the double pass (11 625 ha-1) compared with the controI (3417 ha-1). The treatment also removed between 50 and 60% of the black spruce advance growth of layer origin, which resulted in a 20% decrease in stocking (absolute value). However, when layers and seedlings of black spruce were taken together the stocking reached 60% in both scarification intensities. ln terms of total number of stems, scarification caused a 40% decrease in density coupled with a strong reduction of the layer: seedling ratio (2.7 to 1.6). The general trend shows a significant increase in the growth of layers 6 years after logging. Growth patterns of individual stems suggest that layers with a good growing potential started their height growth increase 3-4 years after logging.
Sector(s):
Forests
Catégorie(s):
Scientific Article
Theme(s):
Forestry Research, Forests, Silviculture
Departmental author(s):
Author(s):
PRÉVOST, Marcel
Year of publication:
1997
Format:
Paper
How to get the publication:
Keyword(s):
silvicultural regime, scarification, site preparation, seedling establishment, layering, boreal forest, seedbed coverage, statistical analysis, growth, black spruce, paper birch, silviculture of plantations, Picea mariana, Betula papyrifera, sylviculture des plantations, plantations, épinette noire, bouleau à papier, régime sylvicole, scarifiage, préparation de site, établissement de semis, marcottage, forêt boréale, recouvrement des lits de germination, analyse statistique, croissance, silviculture and yield of plantations