The canopies of living sagebrush plants can protect new seedlings from extreme temperatures, grazing, and drought, and are often selected as planting sites for restoration after wildfires. However, in some situations these established sagebrush plants—referred to as nurse shrubs-- can also compete with seedlings for space and resources. Researchers investigated the effects of distance from sagebrush canopy on survival of four understory species: Munro’s globemallow, common yarrow, bluebunch wheatgrass, and bottlebrush squirreltail. The authors hypothesized that the highest survival would be just outside the sagebrush canopy, where seedlings could partially avoid competition with established sagebrush while still benefitting from nurse shrub effects. The results for the globemallow and yarrow plants supported this hypothesis: survival was greatest in the intermediate zone, not too close and not too far from the canopy. The survival of the grass species was not related to distance from sagebrush. These results show that the effect of nurse shrubs on seedling survival can vary with species, and that the space between sagebrush canopies may be the best planting site for some.   

Koutzoukis, S., Pyke, D.A., Brunson, M.W., Baggio, J.A., Calzado-Martinez, C., and Veblen, K.E., 2022, Goldilocks forbs- survival is highest outside – but not too far outside – of Wyoming big sagebrush canopies: Restoration Ecology, Online. https://doi.org/10.1111/rec.13919