Revegetation efforts in degraded rangeland systems often fail due to low precipitation and competition from invasive weeds. Use of soil active herbicides, such as imazapic, provides land managers with a tool for controlling invasive weeds. However, when seeding is performed concurrently with herbicide application practitioners struggle with applying herbicide at rates sufficient to achieve weed control without damaging seeded species. We evaluated a novel approach for applying imazapic herbicide and seeding within a one-pass system. Using a John Deer 6330 tractor and P&F Services rangeland drill we mounted a boom sprayer at the front of the tractor, and then at the back of the tractor a tool bar with cultivator sweeps that were adjusted so they were directly in-line with the rangeland drills planter disks. During operation, the cultivator sweeps created a furrow that removed imazapic treated soil away from the drill row. To evaluate each component of the one-pass system we applied the following treatments within a randomized complete block design: 1) drill only (control), 2) cultivator sweeps + drill, 3) imazapic + drill, and 4) imazapic + cultivator sweeps + drill.� Relative to the control,�imazapic + cultivator sweeps reduced�B.�tectorum�cover by 76%. Both cultivator sweep treatments increased volumetric water content in the bottom of the drill row. Imazapic + cultivator sweeps was the only treatment to significantly improve plant density of seeded species, which produced 11.8 plants m-2 in comparison to the control that had 4.5 plants m-2. These results indicate that a one-pass system with imazapic and cultivator sweeps may be an effective method for decreasing weed cover and improving revegetation success.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.