We investigated the joint and separate effects of partial defoliation and pollination on components of reproduction and rhizome carbohydrate reserves in Trillium grandiflorum, a perennial spring ephemeral frequently abundant in the herbaceous understory of deciduous forests in eastern North America. To disrupt annual net production maximally, defoliation treatments were applied during flowering just as the year's flush of leaves matured.Natural pollination limited seed set in one year but not another at our study site near Montreal, Quebec; it is likely that year-to-year variation in pollinator availability is the norm. Removal of leaf or floral bract tissues did not affect mean seed set, but leaf removal did reduce allocation of biomass and nonstructural carbohydrates to rhizomes. As the level of defoliation increased, the correlation between reproduction and storage within plants beca~e increasingly negative. Although the mean seasonal leaf conductance of partially defoliated plants was greater than that of intact plants, any compensatory increases in photosynthesis that may have occurred were apparently insufficient to prevent the reduced allocation to belowground storage. The allocation of resources to current reproduction at the expense of survival and future reproduction possibly reflects the selective effects of unpredictable availability of pollinators for this spring ephemeral.

American ginseng (Panax quinquefolius L.) is an uncommon to rare understory plant of the eastern deciduous forest. Harvesting to supply the Asian traditional medicine market made ginseng North America's most harvested wild plant for two centuries, eventually prompting a listing on CITES Appendix II. The prominence of this representative understory plant has led to its use as a phytometer to better understand how environmental changes are affecting many lesser-known species that constitute the diverse temperate flora of eastern North America. We review recent scientific findings concerning this remarkable phytometer species, identifying factors through its history of direct and indirect interactions with humans that have led to the current condition of the species. Harvest, deer browse, and climate change effects have been studied in detail, and all represent unique interacting threats to ginseng's long-term persistence. Finally, we synthesize our current understanding by portraying ginseng's existence in thousands of small populations, precariously poised to either escape or be drawn further toward extinction by the actions of our own species.

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