Collaborative research: the adapt project: tree seedling adaptation, physiological drivers, and trophic interactions across a latitudinal gradient

The National Science Foundation Division of Environmental Biology awarded Connecticut Agricultural Experimental Station $129,125 on August 1, 2026, for collaborative research on tree seedling adaptation across environmental gradients in the northeastern United States.

The research, conducted under the Biological Sciences program (CFDA 47.074), assesses survival, growth, and seasonal characteristics of over 6,000 seedlings of white oak and chestnut oak species planted across a 430 km transect spanning six provenances from Massachusetts to Tennessee. Seedlings are established in canopy gap plots within forests across four northeastern coastal regions to determine whether early survival and growth respond to differing environmental conditions or remain consistent with their original home environment. The work addresses vulnerability of U.S. forest tree species to generational environmental changes and informs whether transplantation across broad environmental and geographic gradients may be necessary under future management scenarios.

The project includes knowledge transfer between practitioners and researchers, public education and outreach, and training of postdoctoral, graduate, and undergraduate researchers in artificial intelligence and biotechnology. Work is performed in New Haven, Connecticut, with a period of performance through July 31, 2029. The research is conducted in collaboration with the Urban Silviculture Network and the White Oak Genetics and Tree Improvement Program.

Abstract

The goals of this research are to assess tree seedling survival, growth, and seasonal characteristics across environmental gradients and to understand potential ecological consequences of current and future U.S. Forest management practices. Trees in U.S. Forests may be vulnerable to generational changes in environmental conditions. If they do not acclimate to these changes, then transplantation of trees across broad environmental and geographic gradients may be necessary. In collaboration with the urban silviculture network and the white OAK genetics and tree improvement program, over 6,000 seedlings of two OAK species were planted across a 430 KM transect in the northeastern U.S. The trees were planted from acorns that spanned the broad range of white oaks and the narrower range of chestnut oaks in the eastern U.S. They were planted in canopy GAP plots in forests located in four northeast U.S. Coastal regions, and were sourced from six locations spanning massachusetts (northernmost) and tennessee (southernmost). This research will determine whether early survival, growth, and seasonal characteristics change in response to differing environmental conditions, or whether the trees maintain properties consistent with their original home environment. The project will also include: 1) CO-transfer of knowledge between practitioners and researchers; 2) public education and outreach; and 3) education and training of postdoctoral, graduate student and undergraduate researchers in the national priority areas of artificial intelligence (AI) and biotechnology. Nature-based environmental adaptation and mitigation play a significant role in management of U.S. Forests. However, tree species that characterize these ecosystems may be vulnerable to rapid niche shifts. A fundamental question is whether tree species or provenances can adapt to, or migrate with, rapidly changing environmental conditions. If tree species do not acclimate to these changes through adaptive plasticity or natural migration, then conservation interventions, such as assisted migration, may be necessary. The research from this proposal focuses on the adaptive capacity, physiological drivers, and trophic interactions of tree seedlings across multiple latitudes. Collaboratively developed with the urban silviculture network and the white OAK genetics and tree improvement program, a successfully established (97% survival) experiment of >6,000 white and chestnut oaks planted across a latitudinal gradient spanning 430 KM will be utilized for this research. Acorn provenance sourcing spans a greater latitudinal gradient (TN to MA) taking advantage of the native range of white (broad) and chestnut (narrow) OAK. A reciprocal study design was established in 2023 that allows US to decipher whether tree seedlings demonstrate phenotypic plasticity, local adaptation, or environment-adaptive growth and phenological responses across a latitudinal gradient. Our research addresses two vital ecological questions: what is the adaptive capacity of tree seedlings across a latitudinal gradient, and what are the ecological consequences of assisted population migration? Our research objectives are to: 1) assess tree seedling survival, growth, and phenology across the gradient, and 2) explore physiological/chemical mechanisms and trophic interactions/feedbacks with tree seedling growth, phenology, and survival. Broader impacts will include: 1) workforce training and outreach educational programs at the research sites in partnership with the urban silviculture network, 2) CO-transfer of knowledge between practitioners and researchers through this network, and 3) education and training the next generation of scientists. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.- subawards are not planned for this award.