Date of Award

Spring 5-2020

Document Type

Thesis

College

College of Arts and Sciences

Degree Program

Biology

Degree Name

Master of Science

Thesis Advisor

Dr. Jennifer Schafer

Committee Member

Dr. Cynthia Tant

Committee Member

Dr. Kunsiri Grubbs

Abstract

Longleaf pine (Pinus palustris) savannas have been reduced to a small percentage of their original range in the southeastern United States. These savannas are fire-reliant and require frequent, low-intensity fires to maintain understory plant diversity. Currently, many landowners rake pine litter off the forest floor of longleaf pine savannas for subsequent sale in horticulture. Though raking is a common practice, little is known about the effects of raking on the understory plant community, the soil seed bank, or fire intensity. I conducted my research in two longleaf pine savanna sites where raking has occurred. At the McCain Forest Management Area in Hoke County, North Carolina, I investigated the effect of raking on the understory plant community and soil seed banks. I hypothesized that raked areas would have lower species richness and percent cover of understory species than unraked areas. I also hypothesized that raked areas would have a less dense soil seed bank than unraked areas. I worked in five sites (in two study areas) at the McCain Forest Management Area with various raking and burning management histories. Ten plots were established in each study site to estimate understory cover and community composition. Soil samples were taken from each plot twice, four months apart, and soil samples were spread across pots, placed under lights, and monitored for germinants. No differences in species richness or total understory cover were found between raked and unraked sites. The cover of wiregrass (Aristida stricta) was higher in the raked site than the unraked site in one study area. Moderate differences in the cover of wiregrass and dwarf huckleberry (Gaylussacia dumosa) were found in the other study area. A total of 24 germinants were recorded from both seed bank studies. iii At the Sand Hills State Forest located across Chesterfield and Darlington Counties, South Carolina, I aimed to determine if pine litter raking affects understory plant cover, plant size, and fire temperature. I hypothesized that raked stands would have a lower maximum fire temperature than unraked stands. I placed temperature-indicating pyrometers in a raked and unraked stand and measured litter depth and size of longleaf pines, wiregrass, and turkey oaks (Quercus laevis) in each stand. The unraked stand had a deeper litter depth and larger wiregrass and turkey oak individuals than the raked stand. Due to extensive pyrometer damage, differences in fire temperature could not be analyzed. This study found minimal long-term effects of pine litter raking on the composition of the understory community and soil seed bank in longleaf pine savannas. Differences in understory cover found at the Sand Hills State Forest may be due to differences in fire history between sites rather than raking. This study contributes further evidence that longleaf pine savannas do not have a dense long-lasting seedbank.

Available for download on Tuesday, January 12, 2021

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