Seed germination and seedling survival of balsam fir, heart-leafed paper birch, yellow birch, and red spruce along an elevational gradient on Mt. Moosilauke, NH

O'Donoghue, Brigitte
Peter Palmiotto, PhD
Department of Environmental Studies
Balsam fir, red spruce, heart-leafed paper birch and yellow birch seed fall, seed germination, and seedling survival during the first growing season were studied along an elevational gradient on Mt. Moosilauke, NH in 2003. Data on elevation, slope, substrate, and light availability were collected to determine if they affected seed germination or seedling survival. In 2002-2003, birch seeds decreased in number from 64,575 per m² at 833m to 2,720 per m² at 1136m. In the same year, fir seeds increased from 26 seeds per m² at 833m to 1,317 per m² at 1136m. Fewer spruce seeds fell in 2002-2003 than did birch or fir: they ranged approximately 17 per m² at 833m to approximately 73 per m² at 1136m. Few of the seeds from each species germinated and survived to the end of the first growing season; depending on elevation, birch seedling survival ranged from 0.02% to 0.15%, fir survival ranged from 0.1% to 0.33%, and spruce ranged from 0% to 0.15%. Statistical results indicated that increased elevation and canopy cover negatively influenced birch survival, while slope positively influenced survival. Elevation, canopy cover, and slope did not affect fir survival; analysis was not possible for spruce due to its limited number of seeds and seedlings. Overall, birch occurred most frequently on conifer litter. The results from this study will hopefully contribute to a greater understanding of forest dynamics in the northeastern United States, and will provide baseline information from which to study future changes in the forest structure.

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