SHRUBLANDS AND GRASSLANDS ARE OFTEN OVERLOOKED IN WESTERN LANDSCAPES AS UNIFORM AND UNCHANGING.
However, a healthy, functioning sagebrush community can support plant diversity that rivals many riparian areas, and healthy grasslands sequester huge quantities of carbon in soils as well as help capture rain to feed rivers and streams. These ecosystems also constitute the majority of Blue Valley Ranch’s landscape, and so are extremely important to both wildlife and livestock.
Most of the shrublands on the ranch are dominated by mountain big sagebrush (Artemesia tridentata vaseyana), although a 2009 botanical survey found 54 species of shrubs. Nearly all the grass species on Blue Valley Ranch are cool season grasses that tolerate lower temperatures and short growing seasons, which is important in the central Rocky Mountains at elevations above 7,000 feet. Together with a large diversity of forbs and wildflowers, mountain shrub and grasslands provide high quality forage and critical winter habitat for both wildlife and livestock, as well as the iconic and colorful landscape that attracts so many people to Colorado.
Wildlife diversity in shrub and grasslands is also commonly underestimated, with a wide variety of birds, small mammals and insects that call these communities home, as well as the better-known big game and predator species like mule deer, elk or bear. One of the most recognizable species is the greater sage grouse (Centrocercus urophasianus). These birds require sagebrush for cover, nesting habitat, and, from October to April, nearly all of their diet. On Blue Valley Ranch there are two active leks, which are gathering areas where males exhibit their distinctive strutting display to attract females in the early spring.
MANAGEMENT OF SHRUB AND GRASSLANDS ON BLUE VALLEY RANCH HAS FOCUSED ON IMPROVING THE WATER CYCLE AND CREATING SERAL DIVERSITY.
Seral stage refers to any intermediate community of plants between a new disturbance and a climax or mature community, and different plant species are associated with different seral stages, which also support different wildlife species. A landscape with lots of “patches” of plant communities in different seral stages is a landscape with a much higher diversity of both plant and animal species.
Water management in shrublands and grasslands is all about increasing “effective precipitation”, or improving the ability of the landscape to capture and store every drop of precipitation that falls to the ground. Water is the most limiting resource in arid ecosystems, so retaining water in the soil supports healthy vegetation and keeps streams running year-round. Habitat treatments like prescribed burning or good grazing management help to increase ground cover, including litter and live basal vegetation, which keeps ground temperatures cooler and eliminates evaporation of moisture from the soil surface.
Weeds are also a ubiquitous problem in western rangelands. They displace native species, form monocultures that exclude other plant species, and can change moisture and fire regimes. Blue Valley Ranch’s management has always included an integrated noxious weed program.
Wildlife species are the primary beneficiaries of the ranch’s habitat work. However, some wildlife species that were historically present in the Blue River Valley have disappeared, often due to development and habitat loss. As habitat was being improved, Blue Valley Ranch also partnered with Colorado Parks & Wildlife on re-introduction projects to bring back some of those species, including pronghorn antelope (Antilocapra americana) in 1995, Mirriam’s turkeys (Meleagris gallopavo) in 1997, and Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus) in 2006.
THE KEY TO DEFINING WHAT IMPACT BLUE VALLEY RANCH’S HABITAT WORK HAS HAD ON THE LANDSCAPE LIES IN A GOOD MONITORING PROGRAM.
Information and data collected on the ranch’s habitat programs have documented increases in species diversity, ground cover, forage production, and ecosystem health indicators. Unfortunately, sometimes these efforts have also documented trends like an increase in noxious weeds or an acceleration in heavy browsing of new aspen regrowth. But, this is the essence of adaptive management, where problems are identified early so that they can be dealt with as soon as possible.
Wildlife population monitoring on re-introduced species like the pronghorn has verified a well-established herd of over 150 animals in just 10 years. The sharp-tail grouse have at least 2 stable leks which continue to attract more birds every year, and the turkeys have spent every winter at the ranch since the late 90s along the Blue River.
One of the most valuable tools for measuring success in natural resources management is photography. Photos really do speak a thousand words, and repeat photography can show long-term trends in ecosystem health in a way that is quick and easy to understand.