Importance of shrub restoration on great basin rangelands

Authors: Clements, Darin - Charlie; FREESE, MARK - Nevada Department Of Wildlife; SCOTT, MIKE - Nevada Department Of Wildlife; Harmon, Daniel - Dan

Submitted to: The Progressive Rancher
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/26/2016
Publication Date: 7/5/2016
Citation: Clements, D.D., Freese, M., Scott, M., Harmon, D.N. 2016. Importance of shrub restoration on great basin rangelands. The Progressive Rancher. 16(6):8-10.

Interpretive Summary: The recognition of brush species and the browse these plants provide as an important component of rangeland production was often overlooked in land management for some time. Even after the birth of range management in the early twentieth century, herbaceous species were considered the basic component of rangeland forage. Arthur Sampson, one of the founders of scientific range management, was among the first to describe and discuss native range shrubs as components of the basic forage supply on ranges in 1924. By 1931, USDA, Forest Service Ecologist William A. Dayton published Important Western Browse Plants. Dayton was in charge of the range forage investigation for the USDA, Forest Service when the agency published the Range Plant Handbook in 1937. Among the contributors to this publication was Odell Julander, who became a very noted mule deer researcher, and in the handbook stressed the importance of antelope bitterbrush as a critical shrub on winter ranges for deer, elk and antelope as well as recognizing this shrub species as palatable at all seasons and preferred by all classes of domestic large animals, except horses. By the 1940s there was a growing concern over the use of range plants by domestic livestock and its effect on wildlife habitats, especially that for deer. In 1945, Utah State researchers L. A. Stoddart and D. I. Rasmussen entered the wildlife/livestock conflict debate with the publication Deer Management and Livestock where they shared the view that deer and domestic livestock could co-exist on the same rangelands. Joe DiTomaso, Department of Plant Sciences University California Davis noted that rangeland and pasture comprise about 42% of the total land area in the United States and that about 75% of domestic livestock depend on those grazing lands for survival portion of their life cycle. Currently, there are more than 300 species of rangeland weeds in the United States. Western rangelands that were previously dominated by big sagebrush/bunchgrass species are now largely influenced by one of the most notorious aggressive invasive weeds, cheatgrass. In 1999, 1.8 million acres of Great Basin rangelands burned in Nevada alone, many of these acres were critical shrub communities that provided thermal and hiding cover as well as nutritional forage. Early researchers, such as Emor Nord, pointed out that antelope bitterbrush was such a critical browse species that it was referred to as a ‘keystone species’ for mule deer and other wild ungulates in late fall and early winter for its nutritional values. Bruce Welch, U.S. Forest Service plant physiologist reported on the importance of big sagebrush not only as winter forage for wild ungulates and domestic sheep but its importance to species such as sage grouse, black-tailed jack rabbit, pigmy rabbit, dark-eyed junco and white-crowned sparrow. Following the 1999 catastrophic wildfire season 4,322,610 pounds of seed was purchased and drill or aerially seeded on these burned Nevada rangelands. Four-wing saltbush and big sagebrush were some of the shrubs seeded on many burned habitats, yet due to past reports of unsuccessful antelope bitterbrush seeding efforts, not a single pound of antelope bitterbrush was purchased, much less planted. In this paper we focus on two shrub species, antelope bitterbrush and big sagebrush to shed some light as to better understand methods by which to restore these critical shrub species in Great Basin plant communities.

Technical Abstract: The recognition of brush species and the browse these plants provide as an important component of rangeland production was often overlooked in land management for some time. Even after the birth of range management in the early twentieth century, herbaceous species were considered the basic component of rangeland forage. Arthur Sampson, one of the founders of scientific range management, was among the first to describe and discuss native range shrubs as components of the basic forage supply on ranges in 1924. By the 1940s there was a growing concern over the use of range plants by domestic livestock and its effect on wildlife habitats, especially that for deer. The debate over the influences of domestic livestock grazing on wildlife habitats is perhaps as robust and controversial as ever in the history of range management as many grazing permit renewals are challenged in court directly due to possible impacts to wildlife species such as sage grouse (Centrocercus urophasianus) and mule deer (Odocoileus hemionus). Currently, there are more than 300 species of rangeland weeds in the United States. Western rangelands that were previously dominated by big sagebrush/bunchgrass species are now largely influenced by one of the most notorious aggressive invasive weeds, cheatgrass (Bromus tectorum). The accidental introduction, subsequent establishment, and invasion of cheatgrass on rangelands resulted in an increase in the chance, rate, spread, and season of wildfires. This in turn has increased wildfire frequencies from an estimated 60-110 years down to as little as every 5-10 years, simply too short of a time period to allow for the recovery of critical shrub species. In this paper we focus on two shrub species, antelope bitterbrush (Purshia tridentate) and big sagebrush (Artemisia tridenata) to shed some light as to better understand methods by which to restore these critical shrub species in Great Basin plant communities. In southern Oregon, researchers reported that an antelope bitterbrush population of 473 bitterbrush plants/acre only needed the successful recruitment of 6.7 bitterbrush seedlings/year, yet they were only getting 0.7/year. These old decadent stands simply cannot recruit without active management. The USDA-ARS Great Basin Rangelands Research Unit (GBRRU) reported on antelope bitterbrush transplanting success as low as 0% and as high as 27%, fall transplanting experiencing higher success rates than spring transplanting. Direct seeding of antelope bitterbrush experienced excellent success and recruitment of antelope bitterbrush shrubs. Seeding antelope bitterbrush at a seeding rate of 2-3 lb/acre using a rangeland drill resulted in the establishment of 700 to 1,800 plants/acre. Big sagebrush does not have an active wind dispersal system and is not harvested and dispersed by granivorous rodents, so the dispersal of big sagebrush is only about ten feet from the mother shrub. The problem however, is the simple fact that big sagebrush does not survive wildfire, and with the ever-increasing wildfire occurrences and the magnitude of acres affected by these wildfires. Big sagebrush can be direct seeded by placing the seed in the forb box of the rangeland drill, dropping the tubes and allowing the seed to fall to the surface of the soil and avoiding burying the seed too deep in the drill furrows. Fabricating the rangeland drill to pull a culti-packer behind it is an excellent tool at improving the seeding success of big sagebrush. If pulling a triple drill set-up, it is only necessary to put big sagebrush in one of the drills. The GBRRU is just finishing up experiments in which they are recording the success of spring versus fall transplanting of Wyoming big sagebrush in northeastern California and northwestern Nevada. Preliminary data points out that fall transplanting out-performed spring transplanting in all cases averaging