Additional Funding Sources
The project described was supported by NSF Award No. OIA-1757324 from the NSF Idaho EPSCoR Program and the National Science Foundation. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NSF.
Abstract
Artemisia tridentate, big sagebrush, is a vital shrub to ecosystems of the western United States. Multiple species rely upon it for habitat and food throughout the seasons including the greater sage grouse, pronghorn antelope, and jack rabbits. Sagebrush habitat has been threatened by expanding rangeland and more significantly, by fire. Sagebrush is easily destroyed by fires which can be exacerbated by quick burning weeds such as cheatgrass. Bromus tectorum, or cheatgrass, is an exotic weed that has expanded throughout the sagebrush steppe and other parts of the western U.S. After fire, dispersed seeds harbored within the soil seedbank contribute to the regrowth of the vegetation community. Bromus tectorum germinates and establishes quickly after fire, outpacing some native species. In the competition for resources, cheatgrass competes for resources with its neighbors. My graduate mentor, Carson Kantack, is exploring this observation. My question is, does the growth of a cheatgrass seedling affect sagebrush seedling growth differently depending on when that cheatgrass germinates and emerges? My prediction is that, while there will be a competition effect where the cheatgrass pulls resources from the sagebrush inhibiting growth regardless of germination time, the cheatgrass that germinates earlier in the sagebrush seedling development will inhibit growth the most. I will investigate this by planting cheatgrass seeds alongside sagebrush seedlings at three different intervals. I will plant two cheatgrass seeds per single sagebrush seedling at the time of seedling transplant from the germination dish, one week after transplanting, and two weeks after transplanting. In order to ensure that the results are not population specific, I will use Artemisia tridentata tridentate seeds collected from multiple locations. I will use cheatgrass seeds from one population. Results will be determined by analyzing weekly height measurements and biomass data collected at the end of the experiment.
Effects of Emergence Timing on Competition Between Artemisia tridentata subsp. tridentata and Bromus tectorum
Artemisia tridentate, big sagebrush, is a vital shrub to ecosystems of the western United States. Multiple species rely upon it for habitat and food throughout the seasons including the greater sage grouse, pronghorn antelope, and jack rabbits. Sagebrush habitat has been threatened by expanding rangeland and more significantly, by fire. Sagebrush is easily destroyed by fires which can be exacerbated by quick burning weeds such as cheatgrass. Bromus tectorum, or cheatgrass, is an exotic weed that has expanded throughout the sagebrush steppe and other parts of the western U.S. After fire, dispersed seeds harbored within the soil seedbank contribute to the regrowth of the vegetation community. Bromus tectorum germinates and establishes quickly after fire, outpacing some native species. In the competition for resources, cheatgrass competes for resources with its neighbors. My graduate mentor, Carson Kantack, is exploring this observation. My question is, does the growth of a cheatgrass seedling affect sagebrush seedling growth differently depending on when that cheatgrass germinates and emerges? My prediction is that, while there will be a competition effect where the cheatgrass pulls resources from the sagebrush inhibiting growth regardless of germination time, the cheatgrass that germinates earlier in the sagebrush seedling development will inhibit growth the most. I will investigate this by planting cheatgrass seeds alongside sagebrush seedlings at three different intervals. I will plant two cheatgrass seeds per single sagebrush seedling at the time of seedling transplant from the germination dish, one week after transplanting, and two weeks after transplanting. In order to ensure that the results are not population specific, I will use Artemisia tridentata tridentate seeds collected from multiple locations. I will use cheatgrass seeds from one population. Results will be determined by analyzing weekly height measurements and biomass data collected at the end of the experiment.