Title: Pre and Post-Burn Cattle Distribution Patterns: Sagebrush Steppe Authors
|Bohnert, David - OREGON STATE UNIVERSITY|
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: December 1, 2008
Publication Date: February 8, 2009
Citation: Ganskopp, D.C., Bohnert, D. 2009. PRE AND POST-BURN CATTLE DISTRIBUTION PATTERNS: SAGEBRUSH STEPPE. 62nd Society for Range Management Annual Meeting. Paper No.03-11. Technical Abstract: While it is well known that cattle and wildlife are attracted to recently burned locales in many environments, that behavior is not well quantified in the sagebrush steppe. We tracked cattle distribution patterns with GPS collars in two 800+ ha pastures treated with small scale fires on the Northern Great Basin Experimental Range near Burns, Oregon from 2004 through 2007. Burns covered about 3.1 ± 1.5% of the pastures, and prior to the fires those same locales supported about 1.6 ± 1.3% of the June cattle grazing records. In June of the first post-burn growing season, cattle responded by concentrating 29.9 ± 0.6% of their grazing efforts on burned locales. Cattle did not discover or use burned areas that were on steep slopes or the most distant from water in the first post-burn growing season. Elevated nutritional characteristics and lack of standing cured herbage in burned locales were probably the primary attractants for cattle. In the three growing seasons since the fires, mean standing crop crude protein in burned and unburned locales was 13.4 ±1.3% and 10.3 ± 1.6% (P = 0.04) and in situ digestibility averaged 66.9 ± 4.0% and 59.7 ± 3.8% (P = 0.04), respectively. Those contemplating prescribed burns in sagebrush steppe environments should attempt to ignite entire pastures to avoid subsequent heavy and concentrated cattle grazing in treated areas. If one can only treat limited portions of pastures, then cattle entry in the following years should be deferred until recovering herbage has completed its growth cycle and cured.