Sagebrush ecosystems of the Great Basin are rapidly being converted to annual grasslands dominated by invasive weeds such as cheatgrass (Bromus tectorum L.) which thrives following wildfire and competes with native plants. Restoring diverse plant communities containing perennial grasses, shrubs and forbs is an important priority in this region. Scientists in Boise have partnered with public and private agencies to evaluate the effectiveness of seeding techniques designed to re-establish native plants following fire.
Thousands of acres of public land have been seeded following wildfire in recent years. Post-fire seeding is especially important in sagebrush ecosystems where grazing disturbance has often depleted native perennial plants and favored invasive annuals such as cheatgrass. Although techniques for seeding non-native forage plants are well established, these techniques are not always effective for seeding native plant species. Innovative modifications of conventional seeding equipment have the potential to increase success when seeding mixtures of native species with different germination requirements.
Newer models of rangeland drills are able handle seeds of different sizes, planting larger seeds at precise depths in furrows and pressing smaller seeds onto the soil between furrow rows. Many newer drill models are minimum-till drills that have the potential to reduce soil disturbance. Experiments have been replicated at multiple sites in the northern Great Basin to compare the effectiveness of these different drill types for seeding mixtures of native grasses, forbs and shrubs following fire. The minimum-till drill was found to be especially effective for small-seeded species such as Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis), an important ecosystem component that is otherwise slow to re-establish following fire. Other experimental comparisons highlight effects of seeding in different seasons, different seed quantities, and differences due to site-specific conditions and weather patterns.
This research will assist managers in making informed decisions about when, what and how to seed to enhance post-fire recovery in sagebrush ecosystems.