Research Project: Establishing Native Vegetation on Coal Mining Lands

Location: Livestock and Range Research Laboratory

Project Number: 3030-21500-001-007-G
Project Type: Grant

Start Date: Aug 15, 2024
End Date: Nov 1, 2026

Objective:
Plants seeded to disturbed rangelands often fail to establish, which leads to invasion by exotic annual grasses. The first objective of this research is to test whether herbicides and reseeding can be used to address sites that became invaded after the original seeding effort failed.

Approach:
To achieve the first objective, five experiments are being conducted. Each experiment has six plots. With two experiments, herbicide was applied to three plots to deplete invasive annual grass seed banks. Annually, we are testing the soil for herbicide residual. When the herbicide dissipates, plots will be seeded. With the other three experiments, a non-residual herbicide is being applied to three plots to control the current generation of invasive annual grasses. Shortly thereafter, all six plots are being seeded. Then, after the first growing season when seeded plants are tolerant of residual herbicides, a long-lasting soil herbicide is being applied. With all five experiments, vegetation data is being gathered to compare plots where herbicide was and was not applied. To achieve the second objective, five identical experiments have been initiated, and depending on the availability of newly seeded areas on participating mines, we hope to initiate additional experiments. Treatments consist of cool-season grass seed rates and the pre-emergence herbicide indaziflam applied alone or mixed with the non-selective post-emergence herbicide glyphosate. Specifically, the treatments are: 1) Grasses seeded at 0.5 lb/acre 2) Grasses seeded at 1.0 lb/acre 3) Grasses seeded at 6.0 lb/acre 4) Grasses seeded at 0.5 lb/acre and indaziflam 5) Grasses seeded at 1.0 lb/acre and indaziflam 6) Grasses seeded at 6.0 lb/acre and indaziflam 7) Grasses seeded at 0.5 lb/acre and glyphosate plus indaziflam 8) Grasses seeded at 1.0 lb/acre and glyphosate plus indaziflam 9) Grasses seeded at 6.0 lb/acre and glyphosate plus indaziflam Each of these treatments is being replicated twice in each experiment, so there are 18 plots per experiment. Warm-season grass, forb and shrub seed rates are the same in every plot within an experiment. Herbicides are being applied after the first growing season. Vegetation data is being gathered to compare plots where herbicide was and was not applied.