Abstract Changing environmental factors can influence the reproductive phenology of understory herbaceous plants. The article authors investigated the interactions of light (canopy or gap location), deer (exclosure or not), and competition (invasive plants present or removed) on Jack-in-the-pulpit (Arisaema triphyllum), mayapple (Podophyllum peltatum), Solomon’s seal (Polygonatum spp.), and false Solomon’s seal (Maianthemum racemosum) demographics. The authors counted each species’ annual abundance, measured Jack-in-the-pulpit flowering rates and sex ratios, and measured mayapple flowering rates and growth parameters. The presence of deer and invasive species detrimentally affected abundance except for unpalatable Jack-in-the-pulpits. Mayapple growth metrics were highest in the absence of deer. Light and deer exclusion increased flowering rates for both species and shifted Jack-in-the-pulpit sex ratios toward females. Abundance was related positively to reproductive success for Mayapple but negatively for Jack-in-the-pulpit. Overall, deer were the strongest demographic driver, but significant interactions among all variables were prevalent, confirming the necessity to consider interactions among environmental stressors.
Becker et al. (Sun,) studied this question.