Restoration ecology in conflict along the Colorado front range

Abstract

Introduction: Cheatgrass (Bromus tectorum) is a challenge to restoration in western North America. It attracts the attention of academic and government research scientists, weed managers, and chemical companies. Attempts to control it cause conflicts among these groups. Objectives: All agree that protecting biological diversity and ecosystem services on public lands is a central goal. We demonstrate how this goal has been confounded by a rush to endorse chemical methods that motivated the environmental movement of the 1960s. We also examine whether some indaziflam studies are compromised by non-disclosure and conflict of interest. Methods: We review the literature focused on the Colorado Front Range at the nexus between cheatgrass ecology and the chemical control agent indaziflam. Results: Indaziflam is observed to have negative impacts on soil biota, fish, and aquatic invertebrates; to be accompanied by PFAS chemicals; and to induce pesticide resistance. The chemical persists in soils for ~4 years; one of its degradation products (FDAT) is a short-chain PFAS that can leach into ground and surface waters. Indaziflam has now been observed to be genotoxic. Some studies indicate that it can help certain plants reestablish; others demonstrate harm to non-target species. Unlike studies in the Great Basin, we located no research implicating cheatgrass as contributing to extreme wildfires in the Colorado Front Range. Conclusion: Along the Front Range, field data indicate that cheatgrass does not invade plant communities unless there has been disturbance. Absent control measures, recovery from disturbance includes declining cheatgrass cover. The ecological and human health issues motivate against continued indaziflam applications for cheatgrass control in this region.