Long-term understory vegetation surveys under fluctuating deer densities from the Kinzua Quality Deer Cooperative, Pennsylvania

The Kinzua Quality Deer Cooperative (KQDC) was established in 2000 to test new approaches to stewardship of white-tailed deer and forest habitat throughout a 30,000-hectare landscape in northwestern Pennsylvania. Within this landscape, a coalition of land-management partners leveraged multiple tools offered by the Pennsylvania Game Commission to court hunters and intensify white-tailed deer harvest within the region. Understory vegetation plant community responses were tracked over a 20-year period to assess any changes in vegetation diversity and dynamics in response to fluctuations in deer herds. Data summarized in this data publication represent vegetation surveys across a 18-year period (2003, 2011, 2016, and 2021) tracking i) changes in richness and abundance of the entire understory vascular plant community; ii) changes in stem densities of woody regeneration; and iii) changes in abundance, size, and population structure of three liliaceous plants known to be sensitive to deer impact: Trillium spp., Maianthemum canadense, and Medeola virginiana.
Over the period we surveyed vegetation, deer densities dropped by 50% and remained low for over a decade. Then, as deer harvest allocations decreased and hunting seasons shifted, hunting pressure dropped and deer densities rebounded. Thus, the data contained herein allow us to both assess whether understory plant communities show any positive responses in terms of richness, abundance and composition during the era of diminished browse pressure and, subsequently, whether any observed gains are eroded following the increase in deer population densities.
For more information about this study and these data, see Slaughter et al. (in review), Royo et al. (2010), or Rowan et al. (2024).