Pacific Southwest

Title: Factors influencing soil-surface bulk density on oak savanna rangeland in the southern Sierra Nevada foothills

Author: Dudley, Dennis M.; Tate, Kenneth W.; McDougald, Neil K.; George, Melvin R.

Date: 2002

Source: In: Standiford, Richard B., et al, tech. editor. Proceedings of the Fifth Symposium on Oak Woodlands: Oaks in California's Challenging Landscape. Gen. Tech. Rep. PSW-GTR-184, Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture: 131-138

Station ID: GTR-PSW-184

Description: The objectives of this study were to compare soil-surface bulk density between rangeland pastures not grazed since 1935, 1975, and 1995 to grazed areas with a 15-year record of light (>1,000 lbs ac^-1 RDM), moderate (600-800 lbs ac^-1 RDM), and heavy (<400 lbs ac^-1 RDM) grazing by beef cattle; and to determine the influence of oak canopy, topographic position, and livestock concentration activities on bulk density. The study was conducted on sandy-loam soils on oak savanna at the San Joaquin Experimental Range in Madera County, CA. A total of 1047 bulk density samples were collected. Soil-surface bulk density was 19 percent lower under oak canopy than in adjacent open grasslands. Livestock grazing at all levels increased bulk density above that in areas excluded from grazing for 5, 25, and 65 years, while there were no significant differences among exclosures. Areas with light grazing had lower bulk density than moderately and heavily grazed sites, which were not different from each other. RDM recommendations at, or above, 800 lbs ac^-1 will likely lead to reduced soil-surface bulk density on these soil series. Livestock-concentration areas were the most compacted sites in the study.

Keywords: 

View and Print this Publication (260 KB)

Publication Notes: 

• We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
• This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
• You may send email to pubrequest@fs.f ed.us to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)

 Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

Citation

Dudley, Dennis M.; Tate, Kenneth W.; McDougald, Neil K.; George, Melvin R.  2002.  Factors influencing soil-surface bulk density on oak savanna rangeland in the southern Sierra Nevada foothills.   In: Standiford, Richard B., et al, tech. editor. Proceedings of the Fifth Symposium on Oak Woodlands: Oaks in California's Challenging Landscape. Gen. Tech. Rep. PSW-GTR-184, Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture: 131-138.