Off-campus South Dakota State University users: To download campus access theses, please use the following link to log into our proxy server with your South Dakota State University ID and password.

Non-South Dakota State University users: Please talk to your librarian about requesting this thesis through interlibrary loan.


Mary C. Gibbs

Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Wildlife and Fisheries Science

First Advisor

Jonathan A. Jenks

Second Advisor

Charles G. Scalet


big game, habitat, ponderosa pine, custer state park, south dakota, thinning


During the 1980’s , noncommercial thinning of ponderosa pine (Pinus ponderosa) was used to improve big game habitat in Custer State Park, South Dakota. Thinning densely stocked ponderosa pine created more diverse and productive foraging areas for big game species. This study evaluated utilization of forages in thinned pine stands by elk (Cervus elaphus), mule deer (Odocoileus hemionus), and white-tailed deer (Odocoileus yirginianus). The study was conducted in the northwest corner of the park during June, July, and August of 1991 and 1992. The study area included approximately one-third thinned pine, one-third unthinned pine, and one-third recently logged pine. Our treatments consisted of moderately thinned, heavily thinned, and unthinned pine stands. Over 200 plots were clipped in each treatment to measure standing crop each year. Approximately 7,000 individual plants were marked along permanent transects each year and percent utilization by weight was ocularly estimated. Two methods were used to determine utilization. First, the average percent-weight-removed from all marked plants was used, and second, the percent-of-plants grazed was used. Road surveys and pellet group counts were used to determined summer habitat us patterns. Standing crop in thinned pine stands was five times greater in graminoids, three times greater in shrubs, and nine times greater in forbs than standing crop in unthinned pine stands. Utilization of graminoids averaged less than 1% and was not different across treatments. Shrub utilization was higher in thinned stands than unthinned stands when measured as percent-of-plants grazed (2%) (P<0.05). Forbs received higher levels of use in unthinned stands than thinned stands when measured as both percent-weight-removed (8%, 4%, respectively) (P<0.008) and percent-of-plants grazed (18%, 14%, respectively) (P<0.05). Pellet group density was highest in meadows for both elk (600 groups/ha) and deer (275 groups/ha). There was no difference between density of pellet groups in unthinned compared to thinned treatments for either elk or deer. The big game species in this region of the park did not seem to utilize the increased standing crop produced in thinned pine stands.

Library of Congress Subject Headings

Big game animals -- South Dakota -- Custer State Park -- Habitat
Ponderose pine -- South Dakota -- Custer State Park -- Thinning


Includes bibliographical references (page 30-40)



Number of Pages



South Dakota State University


Copyright © 1993 Mary C. Gibbs. All rights reserved.