Study site: This field experiment was conducted over a 20-month period in 5-year-old big sagebush Artemisia tridentate experimental plots near Logan, Utah, southwestern USA. Seedling establishment of the native bluebunch wheatgrass was compared with that of the Eurasian crested wheatgrass Agropyron desertorum in dense big sagebrush stands. In this study, the potential for interseeding grasses into dense shrub communities as a precursor to thinning shrubswas examined. For conservation purposes, native species should be included in restoration projects and retention of some woody plants is desirable. Rehabilitation efforts in sagebrush steppes have tended to focus on shrub removal and introduction of forage grasses to successfully revert from shrubland to grassland.
When combined with intentional fire suppression, overgrazing results in increased dominance of fire sensitive species mostly unpalatable to cattle, such as big sagebush. Heavy grazing eventually leads to a reduction in grasses, which results in the removal of the main source of continuous fuel (i.e.
Many of these semi-arid plant communities are shifting to dominance by woody species as a consequence of land degradation through intense cattle grazing and fire suppression. In the Great Basin region, USA, big sagebrush Artemisia tridentata and perennial tussock grasses, such as bluebunch wheatgrass Pseudoroegneria spicata, co-dominated undisturbed sagebrush steppe communities prior to European settlement.
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