Submitted to: Agricultural Research Service Publication
Publication Type: Other
Publication Acceptance Date: 5/10/2004
Publication Date: 6/15/2004
Citation: Sigua, G.C. 2004. Impact of cattle congregation sites on soil nutrients and soil compaction. USDA-Agricultural Research Service, STARS Field Day Manual, Brooksville, Florida. p. 10-15.
Technical Abstract: This study determined the impact of grazing cattle on the changes in soil quality around and beneath cattle congregation sites (mineral feeders, water troughs, and shades). Baseline soil samples around and beneath three congregations sites in established (>10 yr) grazed beef cattle pastures at the USDA, ARS, Subtropical Agricultural Research Station (STARS), Brooksville, Florida, were collected in July 2002 and July 2003. Soil samples were collected at two depths (0-6 inches and 6-12 inches) at different locations around the congregation sites following a radial (every 45 degrees) sampling pattern at 2.5, 5, 10, 20, 40, 80, and 160 feet from the approximate center of the congregation sites. Concentrations of total inorganic nitrogen, total phosphorus, and the degree of soil compaction varied significantly among the different congregation sites. The highest concentrations of total inorganic nitrogen (2.0 ppm) and total phosphorus (61 ppm) were found at the shade and mineral feeder sites, respectively. The most compacted soil (>230 psi) was from the mineral feeders site. Although the levels of total inorganic nitrogen and total phosphorus were high near the center of the congregation sites, their levels did not increase with soil depth and their concentrations decreased almost linearly away from the center of the congregation sites. Soil compaction tended to decrease away from the center of the mineral feeder sites, but not at the water trough or shade sites. Early results of the study are suggesting that cattle congregation sites in beef cattle operations in Florida are not nutrient rich and may not contribute more nutrients to surface and ground water supply under Florida conditions. Since there is no vertical buildup or horizontal movement of inorganic nitrogen or total phosphorus in the landscape, we can then surmise that cattle congregation sites may not be considered a potential source of nutrients at the watershed level.