Effect of Forest Canopy Density on the Distribution of Five Rubus Species in Central Pennsylvania
Open Access
Author:
Showalter, Levi
Area of Honors:
Forest Ecosystems Management
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Eric Paul Burkhart, Thesis Supervisor Margot Wilkinson Kaye, Thesis Honors Advisor
Keywords:
Rubus Rubus phoenicolasius Rubus allegheniensis Rubus occidentalis Wineberry Raspberry Blackberry Forest Canopy Invasive Species Wine Raspberry
Abstract:
The genus Rubus, comprising the raspberries, blackberries and other brambles, includes many familiar plants in Pennsylvania’s forests. These species have important effects on the dynamics of the broader ecosystem, and their distribution is impacted by light availability to the understory. In this research, I examined the distribution of five different Rubus species at three sites in central Pennsylvania and compared the levels of canopy density present over each species. By comparing the results of t-tests between samples of flowering and non-flowering Rubus plants, I determined that the invasive R. phoenicolasius (wineberry) competes most directly with the native R. allegheniensis (Allegheny blackberry), a key early-successional species that is important for forest regeneration. These are then followed by R. occidentalis (black raspberry) and the low-growing dewberries as the forest develops and the canopy becomes more shaded. Understanding these patterns of Rubus succession can help foresters to develop more effective management plans for encouraging native plant regeneration for both economic and wildlife value, while combating the proliferation of invasive species.
