Plant Ecology and Climate Change Lab
RESEARCH
Video presentation prepared for 2022 Botanical Society of America national meeting describing some results from our work with phenological escape
Trout lily (Erythronium americanum) are true spring ephemerals that emerge from dormancy several weeks before the canopy closes and they retreat to dormancy belowground.
Projected change in spring light window duration for spring-active wildflower species in a) eastern Asian, b) Europe, and c) eastern North America (Lee et al, 2022)
Dioecious plant species, such as the northern spicebush (Lindera benzoin) shown above, have male and female flowers on separate individual plants, necessitating outcrossing for successful reproduction.
Jack Hatajik counting the number of flowers, buds, and fruits for an individual Alliaria petiolata at Pymatuning State Forest.
Shifts in phenological escape in response to climate change​
Spring-active understory plants in temperate deciduous forests assimilate 50-100% of their annual carbon budget within the first few weeks of the growing season, prior to canopy closure, a strategy known as phenological escape. Climate change, specifically spring warming, is shifting canopy tree phenology earlier, meaning that understory spring light windows could also shift depending on the sensitivity of understory plants. In order to maintain access to this ephemeral resource, spring-active wildflowers and woody plants like tree seedlings must shift their phenology at the same or greater rate as the canopy.
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We recently wrote a primer on the topic of phenological escape and are working to fill in some of the remaining knowledge gaps on the subject that we identified. We currently employ field observations and experiments, analyses of existing herbarium and community science datasets, and growth chamber twig experiments to answer these questions with a focus on native species in southern Appalachia.
Phenological mismatch between plants and other organisms
Phenological mismatch occurs when species pairs have different sensitivity to the environmental cues that trigger repeated life history events like flowering, pollinator activity, and migration. It can result in reduced or weakened interactions between species that historically interacted or it can manifest as increasing interactions between species that were previously did not interact. Either way, phenological mismatch often causes disruptions to biotic interactions that shape competition for resources and organismal fitness. These changes are becoming increasingly common in response to climate change.
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Phenological escape, described above, is a type of plant-plant competition mismatch. In the PEACCH Lab we also study plant-pollinator mismatch, plant-herbivore mismatch, and flowering mismatch in dioecious plant species. Further, beyond just quantifying whether the mismatch occurs, we work to directly and mechanistically link mismatch to plant fitness and demography.
Invasion dynamics of Alliaria petiolata and effects on AMF communities
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Garlic mustard (Alliaria petiolata) is an invasive plant originating from Eurasia that is now common across much of the contiguous United States. Previous work found that garlic mustard is allelopathic and produces glucosinolates, which acts to restrict AMF sporulation and can therefore impact AMF interactions with native plant species. However, it is currently a matter of debate as to how much of an effect this has on native plant communities and whether these effects are consistent across time and space. For example, work from Lankau et al. (2009) suggests that allelopathic effects of garlic mustard disappear as a function of time since invasion.
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We are investigating the invasion history of garlic mustard across Pennsylvania and to determine if time since invasion is a good predictor of garlic mustard abundance and performance, biodiversity of native plant communities, or composition of belowground mycorrhizal communities.