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Goldenseal ( Hydrastis canadensis ) is a North American perennial clonal herb highly prized for its medicinal value. It is threatened at the northern range limit with only 20 populations known in Canada. To assist recovery planning, 13 populations were sampled to model dynamics. The fate of all ramets in one square-meter was monitored from 1998 to 2001. Transition matrices were built for 2000–2001, using three stage classes based on size and reproductive status. A six-stage pooled matrix, separating established ramets from newly produced ramets, was also constructed. Recruitment by seed was not observed and therefore excluded. The average population growth rate ( λ ) was 1.062 ± 0.053, which did not significantly differ from the equilibrium value (1.0) suggesting that the northern population is stationary. However, growth rates among population samples varied largely and had wide confidence intervals. Populations with λ -values less than or close to 1.0 require environmental change to increase. Recovery of goldenseal, and possibly other woodland perennials at risk, requires intervention aimed at population size augmentation, habitat optimization, and targeted dispersal.

The prevalence of secondary forests is increasing across tropical landscapes, but the effects of these environments on the population dynamics of understory species and on their capacity to regenerate after harvest remains poorly documented. We compare the population dynamics of the understory bromeliad, Aechmea magdalenae, between old-growth and secondary rainforests in Southeast Mexico. A. magdalenae is a non-timber forest product (NTFP), the ramets of which are harvested from wild populations to make forest plantations. The fates of 600 rosettes in the two forest types were monitored over 3 years to build annual transition matrices. Population projections using the matrices show that secondary forest populations have finite rates of growth significantly higher than those of old-growth populations under both ramet-harvest and no-harvest conditions. Life table response experiments indicate that differences in the capacity for re-growth after harvest was due to greater vegetative reproduction of the largest secondary forest rosettes and faster growth of their ramets. For understory NTFP such as A. magdalenae, secondary forests may offer more economic incentive and greater potential for forest conservation than old-growth forests.

On the west coast of Newfoundland (Canada) about 40% of the provincially rare plant species are not protected within the system of three national parks and two ecological reserves existing in the region. This study examines how heuristic algorithms can be used for selecting areas filling this gap while minimizing potential land use conflicts. One algorithm selected 78 areas of 1 km 2 each, representing the minimum set of areas that includes all species at least once. Only 13 out of these 78 areas were selected from existing protected areas; therefore, 65 would have to be added to this system to achieve full representation. A second algorithm reduced this number to 55 by seeking, from the beginning, only species not included in existing protected areas. A third algorithm constrained the choice of complementary areas to those that would have the lowest potential for conflicting land use (CLU). With this algorithm, however, full representation of rare plants within protected areas would need 79 areas instead of 55, i.e. trying to minimize the number of potentially conflicting areas entails selecting a significantly larger number of areas to achieve the same conservation goal. An index such as the CLU proposed here adds to the value of heuristic selection algorithms as indicative tools for planning a network of protected areas.