A history of plant improvement by the USDA-ARS Forage and Range Research Laboratory for rehabilitation of degraded western U.S. rangelands

Authors: Staub, Jack; Chatterton, N; Bushman, Shaun; Johnson, Douglas; Jones, Thomas; Larson, Steven; Monaco, Thomas; Robins, Joseph

Submitted to: Rangelands
Publication Type: Review Article
Publication Acceptance Date: 8/25/2016
Publication Date: 10/30/2016
Citation: Staub, J.E., Chatterton, N.J., Bushman, B.S., Johnson, D.A., Jones, T.A., Larson, S.R., Monaco, T.A., Robins, J.G. 2016. A history of plant improvement by the USDA-ARS Forage and Range Research Laboratory for rehabilitation of degraded western U.S. rangelands. Rangelands. 38:233-240.

Interpretive Summary: Predicted climate change models for semi-arid regions of the western U.S. indicate seasonal weather patterns of several environments will likely change (e.g., warmer winters in the Great Basin and hotter, drier summers in the Mojave Desert), increasing the already high rate of rangeland and pasture degradation, which in turn will increase annual grass invasion, escalate wildfire frequency, and reduce forage production. These changes in western U.S. rangelands will continue to result in the emergence of novel ecosystems that will require different and/or improved plant materials for revegetation. Traditional plant improvement of native and non-native rangeland plant species by the USDA, ARS Forage and Range Research Laboratory (FRRL, Logan, UT) is accomplished through rigorous evaluation of seed collections followed by recurrent selection and hybridization of unique plant types within selected populations to characterize plants adapted to novel ecosystems. After such plant types have been identified, they are further evaluated in multiple ecologically diverse locations to distinguish broadly adapted superior germplasm for public release. Plant improvement of perennial grasses, legumes, and forbs by the FRRL has provided and will continue to deliver plant materials that support sustainable rangeland management efforts to service productive and biologically diverse rangelands. Such improved plant materials enhance likelihood of success of restoration efforts on degraded rangelands, and, thus, increase producer profits, reduce adverse effects on wildlife, and increase the quality of recreation activities by humans.

Technical Abstract: The semi-arid and arid rangelands and irrigated pastures of the western U.S. provide a broad array of ecosystem services, includig wildlife/livestock feed, a diversity of native plants, pollinators, wildlife, and recreational activities. However, disturbances by wildfire, livestock, wildlife, and humans (including recreational activities) have contributed to degraded conditions on much of America's 800 million acres of rangeland. Many of these regions have been classified as severely disturbed and non-productive, resulting in emergence of novel ecosystems (i.e., emergence of species that occur in combinations and relative abundances that have not occurred previously within a given biome). Moreover, based on predicted climate change models for semi-arid regions, seasonal weather patterns of several environments in the western U.S. will likely change (e.g., warmer winters in the Great Basin and hotter, drier summers in the Mojave Desert), increasing the already high rate of rangeland and pasture degradation and resulting in the spread and dominance invasion of annual grass species, more frequent wildfires, and reduced forage productivity. Thus, in water-limited environments of the western U.S., there is a need to develop grasses, legumes, and forbs that will establish under drought, compete with invasive weeds, and persist with adequate feed production and quality to meet the needs of wildlife populations and livestock throughout the year. The Forage and Range Research Laboratory (FRRL) in Logan, UT has historically provided improved plant materials and management alternatives for sustainable stewartship of rangelands, pastures, and turf in the western U.S. Research by the FRRL is performed at 38 field locations in the greater Intermountain West from the Mojave Desert north to the Scablands of Washington state, west to central Nevada, and east to the western edge of the short grass prairie of the U.S. Through evaluation and breeding of native and non-native species, the FRRL has developed over 50 plant materials that are used broadly on western rangelands and pastures. Plant improvement involves domestic and foreign collection of seeds, evaluation of collections to identify their potential for agriculture, and breeding of selected collections to develop improved plant material. Since 1977, FRRL scientists have made more than 10,000 overseas and domestic seed collections. Overseas collections have come from 17 countries (mainly Central Asia), while domestic collection expeditions have focused primarily on germplasm resources in the 11 western states, with collections also being made in Alberta and British Columbia Canada. These collections are evaluated by the FRRL in multiple locations for plant improvement potential in observational and replicated trials, and remnant seed of the original collections is sent to the U.S. National Plant Germplasm System (NPGS), a repository that maintains seed and vegetative collections of important crop species and their wild relatives. These collections provide the genetic basis for selection and release of rangeland germplasm with enhanced tolerance of abiotic stresses (e.g., drought and salinity) and successful rehabilitation of novel ecosystems (i.e., where often distinct changes in ecological function have occurred). Improved plant materials enhance likelihood of success of restoration efforts on degraded rangelands, and, thus, increase producer profits, reduce adverse effects on wildlife, and increase the quality of recreation activities by humans.