| Abstract Detail
Ecological Section Antlfinger, Ann [1], Garabrandt, Marjorie [1]. Stage-structured demography of a Nebraska population of Panax quinquefolius (1987-2007).. In 1987, we discovered an undisturbed population of Panax quinquefolius in Omaha, NE, which is on the western edge of its range. Our objective was to describe the status of this population (called Neale Woods) by estimating annual growth rate, stage structure, and recruitment of seedlings. Individuals are scattered over a large area in groups of 1-45 each. A total of 264 plants have been permanently numbered since 1987. Each May, a census was made, plant height measured, prongs and leaflets counted and the presence of an inflorescence noted. Fruit production was determined in July or August. The size of the Neale Woods population has varied from 78 marked plants in 2006 to 140 in 2001 (113.8 ± 3.4, N = 20). Most years, the majority of plants had 3- or 4-prongs, suggesting the population has persisted for a long time. Over half of the 3- (57.5%) and 4- (54.5%) prong plants, marked in 1987, are still alive. The mean annual growth rate (Nt+1/Nt) for the Neale Woods site was 0.99 ± 0.03 over 19 transitions (range: 0.7-1.2). Thus, the population is stable in size. Flowering and fruit production is concentrated in the 3- and 4-prong classes. Annual seed production ranged from 16 to 634 for the population. The number of new seedlings recruited was low (range: 0-22; mean: 5.4 ± 1.2, N = 20). Seedling survival decreased rapidly in the first five years, losing 20-60% of the cohort. Our results suggest that the Neale Woods population would maintain itself, if left undisturbed. A minimum viable size of 170 has been reported for American ginseng. The Nebraska population is smaller than this, and therefore, harvesting is not advised.
Log in to add this item to your schedule
1 - University of Nebraska Omaha, Department of Biology, 114 Allwine Hall, Omaha, Nebraska, 68182-0040, USA
Keywords:
Panax
ginseng
demography
seedling recruitment.
Presentation Type: Oral Paper:Papers for Sections
Session: CP55
Location: Boulevard A/Hilton
Date: Wednesday, July 11th, 2007
Time: 1:15 PM
Number: CP55002
Abstract ID:1509 |
