Big Sagebrush Seedling Competition with Variable Densities of Cheatgrass

Big Sagebrush (Artemisia tridentata) is a foundation species that provides important habitat for many native wildlife of the Intermountain West. The seedling stage of sagebrush has not been studied extensively, however the seedling stage seems to be a high mortality period of sagebrush. For Big Sagebrush to germinate there needs to be specific conditions. Cheatgrass (Bromus tectorum) is an invasive species which has spread throughout the western U.S. Cheatgrass causes problems for wildlife and livestock foraging on the sagebrush steppe due to the plant not being edible for most of the year and crowding out other vegetation. Cheatgrass can lead to more frequent and hot fires due to how quickly it dries out leaving very flammable material throughout the landscape. In my experiment I am comparing sagebrush growth in the seedling stage with different densities of cheatgrass. This experiment will be done in a greenhouse setting to limit the environmental variation including water and potential disturbances. First to get germinated seeds I will be using a cold treatment then putting them in a growth chamber to simulate the springtime to germinate. I will be using two subspecies of big sagebrush A. tridentata ssp. tridentata and A. tridentata ssp. wyomingensis using 45 seedlings from each subspecies. To limit variability among cheatgrass individuals, I will be using cheatgrass seeds from one maternal line. From the results of this experiment, we could find management applications if it is found that sagebrush seedlings grow better at higher or lower cheatgrass densities or if one subspecies competes better at the seedling stage. This kind of information could help restoration efforts of sagebrush in cheatgrass infested areas to know which areas to target and which subspecies to target