Repository logo
 

Pyric herbivory in the northern mixed grass prairie: testing the use of fire as a land and livestock management tool on rangelands in Saskatchewan

Date

2020-11-02

Journal Title

Journal ISSN

Volume Title

Publisher

ORCID

Type

Thesis

Degree Level

Masters

Abstract

The plant communities of the Great Plains of North America evolved with fire and grazing by bison. With the arrival of Europeans settlers, bison herds were hunted to near extinction, fires were suppressed, and the natural disturbance processes occurring on the prairies were altered. Cattle are now the main source of grazing disturbance on native prairie. Cattle and bison cause different impacts on grasslands and grassland community structure, due to differences in management practices, foraging preferences, and social behaviours. Fire is a natural disturbance which creates a landscape that is variable in vegetation structure, composition, and biomass. Both cattle and bison seek out recently burnt areas, leaving other areas on the landscape to recover from previous grazing. The attraction to burnt areas further promotes a heterogeneous landscape that varies in maturity, structure, and composition. Heterogenous landscapes are important to maintaining an environment that provides habitats to many at-risk grassland species. While the use of prescribed fire as a livestock and land management tool has been study extensively in the in the prairie ecosystems of the United States, few studies have examined the interaction of fire and grazing animals (i.e., pyric herbivory) in the northern mixed grass prairies in Canada. In this study, I examined the short-term effects of two spring prescribed fires on plant community structure in native prairie and tame forage pastures in the northern mixed grass prairie region. I also examined the influence of prescribed fire on cattle movement within these pastures by tracking their movements in the grazing season preceding and following the burns. Prescribed fire reduced total plant and litter biomass, however there were strong climatic influences on vegetation with significant season and annual changes in biomass. Burning homogenized vegetation composition in both pastures in the growing season following the prescribed fires. Finally, I saw a significant increase in cattle visitation to the recently burned areas within the pastures. Pyric herbivory in the northern mixed grass prairies of Canada appears to be a worthwhile land and livestock management tool to promote grassland conservation while maintaining a viable livestock operation.

Description

Keywords

pyric herbivory, northern mixed grass prairie

Citation

Degree

Master of Science (M.Sc.)

Department

Plant Sciences

Program

Plant Sciences

Citation

Part Of

item.page.relation.ispartofseries

DOI

item.page.identifier.pmid

item.page.identifier.pmcid