Location: Great Basin Rangelands ResearchTitle: Lawson Aerator applications on rangelands
|Clements, Darin - Charlie|
|MCLAIN, JOHN - Resource Concepts|
|WHITE, JEFF - Newmont Mining Corporation|
|Harmon, Daniel - Dan|
Submitted to: The Progressive Rancher
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/23/2016
Publication Date: 1/3/2017
Citation: Clements, D.D., McLain, J., Weltz, M.A., White, J., Harmon, D.N. 2017. Lawson Aerator applications on rangelands. The Progressive Rancher. 17(1):36-38.
Interpretive Summary: Heavy duty implements designed and built for manipulating rangeland vegetation and soils have been around for many decades. In the 1950’s, the early developments of Rangeland drills resulted in the effective seeding of hundreds of thousands of acres of deteriorated rangelands to perennial grasses in an effort to increase the forage base for the livestock industry and reduce the spread of the noxious weed, halogeton. Rangeland drills, brush hogs, Dixie harrows, tandem discs and other equipment have played an important role in treating degraded rangeland environments. The Lawson Aerator is one of the newer implements to enter the scene for rangeland improvements. The aerator has significant weight distributed over 2 tandem drums that are 12’ x 3’ diameter with an option of adding liquid to the drums for additional weight. The drums display angled, protruding and spaced 8” x 4” x 1” steel plates with sharpened ends for effective chopping of woody material and penetration into soils for aeration. The variable pitch between the bladed drums can be adjusted to reduce or increase the impact to vegetation. The Lawson Aerator can provide a valuable tool when trying to restore or rehabilitate plant communities that are degrading due to old decadent brush stands or the encroachment of Pinon-Juniper. We measured an increase in over 300% herbaceous density as well as significant edge effect and stand age improvement on lands treated with the Lawson Aerator.
Technical Abstract: Rangeland drills, brush hogs, Dixie harrows, tandem discs and other equipment have played an important role in treating degraded rangeland environments. The Lawson Aerator is one of the newer implements to enter the scene for rangeland improvements. The Lawson Aerator was designed as a pasture renovator in southern states for pastures that were being invaded by woody species, this equipment has earned a solid reputation and since found its way West. We tested the use of the Lawson Aerator at two separate sites in northern Nevada. The first site, Flying M Ranch is an arid, degraded Basin and Wyoming big sagebrush community where seeded a variety of native and introduced grasses, forbs and shrubs in the fall of 2012. A rangeland drill was pulled behind the Lawson Aerator to drill seed the native and introduced perennial grasses, forbs and shrubs. In the spring of 2013, the crushing of the big sagebrush plants resulted in the release of residual herbaceous species as well as very good seeded species emergence, 37/m². Precipitation for 2012-2013 was only 3.6”, therefore many of the seedlings that did not get preyed upon by black-tailed jackrabbits perished with such aridity. By September 2014, the treated plots averaged less than 1 seeded species/m², but showed an increase in residual plant species such as creeping wildrye, 2.6/m², and big sagebrush resprouts and seedlings at 0.08/m². The second site, Simpson Creek Ranch is a site dominated by old, decadent Wyoming big sagebrush and encroaching Pinon-Juniper. The site was treated in 2011 and 2012 and then seeded with crested wheatgrass using a rangeland drill and the broadcasting of ‘Immigrant’ forage kochia. The seeding was very successful as witnessed by the perennial grass crested wheatgrass vigorously growing in the seeded rows, 10/m² and “Immigrant’ forage kochia densities averaging just over 2/m². The application of the Lawson Aerator at the Simpson Creek Ranch resulted in an improved vegetative class and structure that resulted in a new sage grouse breeding ground, lek, and increased wildlife use as well as more than a 300% increase in herbaceous grazing resources.