Prescribed fire drives divergent invasive annual grass responses in a dry forest-mosaic

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We use field data collected before and after a prescribed burn in eastern Oregon, USA, to uncover how prescribed fire impacts three problematic invasive annual grass species, cheatgrass, ventenata, and field brome and understory plant communities for 3 years after burning in a dry forest-mosaic landscape. Plant communities shifted towards invasive dominance over time regardless of burning. All three invasive annual grass species recovered within 2 years of burning to at or above pre-treatment levels and continued to increase in cover over time. Ventenata increased at the fastest rate across both burned and unburned areas, averaging less than 10% in 2016 to nearly 20% in 2020. This increase was slightly slower in burned areas than in unburned areas.