Effects of Mechanical Treatments and Climatic Factors on the Productivity of Northern Great Plains Rangelands

Abstract

Authors arerangescienrist USDA-ARS, Fort Keogh Livestockand Range Research Loboratory, Miles City, Mont. 59301; research animal scientist USDA-ARS, Forage and Livestock Research Laboratory, El Reno, Okla. 73036; range ecologist USDI-BLM, Oregon State University, Corvallis, Ore. 97331; range scientist and research leader, and range scientist (retired) USDA-ARS, Fort Keogh Livestock and Range Research Laboratory, Miles City, Mont. 59301. Abstract Impacts of 7 range treatments and climate on late spring herbage standing crops (SC) were measured in rangelands near Miles City, Mont., from 1983 to 1990. Treatments, established in 8 pastures at 2 sites, were: (1) untreated control + season long grazing (SL); (2) soil tillage (ST) + SL; (3) ST + drill seeding legumes (DS) + SL; (4) brush control (BC) + ST + DS + switchback grazing (utilizing 2 pastures); (5) BC + ST + DS + SL; (6) ST + nitrogen fertilization + SL; and (7) contour furrowing (CF) + aerial seeding legumes + SL. Data were analyzed using years as a repeated measure. Treatments increased (prO.05) total SC 320 kg/ha over controls, but did not affect species/species group composition. Treated pastures produced similar (p10.10) SC of 881 kg/ha. Total SC averaged 490 kg/ha more (p10.05) in 1983,1986,1987,1989, and 1990 than in 1984,1985, and 1988. Perennial cool-season grass SC was greatest in 1986 (651 kg/ha). Peak annual grass SC (337-506 kg/ha) occurred in 1983 and 1984, the 2 years following ST or CF, and 1989 and 1990, the 2 years following severe drought. Although regression analyses showed fall, winter, and spring precipitation and temperature were closely related to spring SC, less than 50% of the variation in SC was accounted for when precipitation and temperature were summed on a l-month, 2-month, or 3-month basis. Above-average fall and spring precipitation (September and April) resulted in the greatest total SC. Species composition varied temporally with changing weather conditions and management strategies.

Aboveground Net Primary Productivity and Cover of Vegetation Exposed to Various Disturbances in Arid Argentina

“…Bartos et al (1994) and Cook et al (1994) reported similar results. Other studies have reported an increased forage production after mechanical disturbances in rangelands (Griffith et al, 1985), very likely because of the release of plant nutrients as a result of soil disturbance (Haferkamp et al, 1993). This might be because total ANPP was higher in the Old Field 1 and/or Old Field 2 than in the other disturbance types during most of the study years.…”

Fort Keogh Livestock and Range Research Laboratory's Historic Role in the Settlement of the West and Present Contributions to Range Ecology and Livestock Research

“…Annual bromes are cyclic in the Northern Great Plains and depend on the amount and distribution of moisture, temperature, and seedbank. 9 Fort Keogh research has demonstrated the potential to severely affect the fertility of annual brome seeds with low-level herbicide treatment. 10 More information on past and current research at Fort Keogh can be found at http://www.ars.usda.gov/Main/docs.…”

Contour ripping is more beneficial than composted manure for restoring degraded rangelands in Central Texas

“…One early study by the Forest Service in New Mexico (Dortignac and Hickey, 1963) found that runoff and erosion were reduced following contour ripping. In addition, a number of studies have documented the positive effect that contour ripping has on vegetation (Griffith et al, 1985;Haferkamp et al, 1993;Miyamoto et al, 2004;Wight et al, 1978).…”