Land-use legacies and recovery from dry farming in sagebrush ecosystems of the Great Basin, USA

Authors: MORRIS, LESLEY - Utah State University; Monaco, Thomas; Sheley, Roger

Submitted to: Ecological Applications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/10/2011
Publication Date: 7/22/2011
Citation: Morris, L.R., Monaco, T.A., Sheley, R.L. 2011. Land-use legacies and recovery from dry farming in sagebrush ecosystems of the Great Basin, USA. Ecological Applications. DOI: 10.2111/REM-D-10-00147.1.

Interpretive Summary: Agricultural land-use is known to alter landscapes and ecological processes for long periods of time. Recovery following cultivation in sagebrush ecosystems of the Great Basin remains largely unexamined. We hypothesized that this historic land-use has changed the vegetation at these sites. We found that recovery from cultivation is variable by growth form, species, and by ecological site. Shrub recovery was different among Artemisia species. This study demonstrates that land-use legacies of dry farming have striking consequences on vegetation recovery for nearly a century after cultivation has ceased. Land-use legacies in sagebrush ecosystems have direct implications for describing ecological site conditions and predictions about how ecosystems respond to restoration and re-vegetation efforts.

Technical Abstract: Agricultural land-use is known to alter landscapes and ecological processes for long periods of time. In particular, native plant communities can take decades to centuries to recover from the disturbance of cultivation. Recovery following cultivation in sagebrush ecosystems of the Great Basin remains largely unexamined even through millions of acres of land were cultivated and then abandoned after the dry farming boom from 1910-1920. Some old dry-farmed fields can still be identified in aerial photos approximately 90 years after cultivation ceased in the northern Great Basin. We hypothesized that this historic land-use has changed the vegetation at these sites. To test this hypothesis, we evaluated the differences in canopy cover of shrubs, grasses, and forbs in three different ecological sites using paired sets of historically dry-farmed land and adjacent areas that have never been cultivated. We found that recovery from cultivation is variable by growth form, species, and by ecological site. Shrub recovery was different among Artemisia species. Chrysothamnus viscidiflorus and Sarcobatus vermiculatus, which often increase following disturbance, maintained higher cover inside old fields. At one of the paired sets, shrub composition was completely altered from a mix of four species to dominance of only Artemisia tridentata. Total forb cover was generally lower in old fields; and some species, like Phlox hoodii, had not recovered. The most common grass species encountered across all ecological sites, Elymus elymoides, had higher cover inside old fields. Surprisingly, introduced annual species, including Bromus tectorum, did not dominate these sites as they have for decades following agricultural abandonment in other areas of the Great Basin. This study demonstrates that land-use legacies of dry farming have striking consequences on vegetation recovery for nearly a century after cultivation has ceased. Land-use legacies in sagebrush ecosystems have direct implications for describing ecological site conditions and predictions about how ecosystems respond to restoration and re-vegetation efforts.