Pre and post treatment (2016-2021) vegetation cover for three southwest Idaho sites treated with pre-emergent herbicides after fire

Selective herbicide application is a common restoration strategy to control exotic invaders that interfere with native plant recovery after wildfire. Whether spraying with preemergent or bioherbicides releases native plants from competition with exotics (“spray-and-release” strategy) and can make communities resistant to re-invasion by exotic annual grasses (e.g., cheatgrass, medusahead), without risks to non-target native plants or secondary invasion, is a major question for land managers of semiarid plant communities.
We applied chemical herbicides (imazapic, rimsulfuron) and weed-suppressive bacteria (Pseudomonas fluorescens strains MB906 and D7) to three different SW Idaho sagebrush-steppe communities after fire. We measured plant cover prior to burning and for four years after treatments.