Schwinning Lab

Pastures dominated by invasive grasses such as old world bluestems and Bermudagrass are frequent sights in the Texas Hill Country.

Creosotebush (front) and burroweed (back) transplants in a common garden near Joshua Tree National Park

Oil and gas exploration produces innumerable islands of bare, compacted and depaupered soil.

Our most recent project is a prairie restoration experiment conducted at the Dowell Ranch in Austin, a property of the Native Prairie Association of Texas, who sponsors this research. The research is led by graduate student Owen Moorhead, with Dr. Kelly Lyons of Trinity University in San Antonio serving as a collaborator. The experiment will determine best management practices to restore an invasive-species dominated pasture to diverse native prairie using a variety of restoration techniques, uncluding herbicide and fire, seed drilling and plug planting.

We are also engaged in the Ecological Restoration of arid lands, with our collaborative partners Dr. Lesley DeFalco and Dr. Todd Esque of USGS, Henderson, Nevada. Graduate student Nathan Custer conducted his thesis research on an ongoing multiple common garden experiment in the Mojave Desert. Nathan identified ecotypic variation within species of creosotebush, burroweed and desert globemallow in populations collected across the Mojave Desert. Information about population differences in winter drought resilience and capacity for summer resource use helps to establish which ecotypes are best adapted to tolerate future climate patterns at restoration sites.

Graduate student Logan Maxwell worked with USGS to determine the costs and benefits of blackbrush (Coleogyne ramosissima) and sagebrush (Artemesia tridentata wyomingensis) restoration on abandoned oil and gas exploration sites on the Colordao Plateau. The focus here is on determining the main barriers to seedling establishment, including soil compaction, loss of top soil, loss of nurse plant cover and lower soil moisture. A set of experiments repeated at several drill sites examined the effectiveness of several restoration methods to weigh the efficiency of these methods against their costs. Our goal is determine which combination of methods results in the optimal outcome in terms of the amount of land area restored, the length of time it took and the total cost of restoration.

Earlier, graduate student Lisa Jones conducted a blackbrush restoration experiment with USGS along an elevation gradient near Primm, Nevada. The work highlighted how the major restoration barriers shift from herbivory at the more productive higher elevations to drought mortality at the harsher lower elevations. This suggests that restoration methods should be carefully calibrated to local site conditions.

Ruckman, E., Schwinning, S., Lyons, K. 2011. Rainfall - burn time interactions in the recovery of an invasive grass after prescribed burn. Restoration Ecology 20: 756 - 763. pdf

Havill, S. Schwinning, S., Lyons, K.G. 2015. Fire effects on invasive and native warm-season grass species in a North American grassland at a time of extreme drought. Applied Vegetation Science 18:637-649 pdf

Jones, L.C., Schwinning, S., Esque,T.C. 2014. Seedling ecology and restoration of blackbrush (Coleogyne ramosossima) in the Mojave Desert, United States. Restoration Ecology 22: 692-700 pdf