Determining grazing intensity on rangetand

Excerpt

GRAZING management on range-land is based on controlling the timing, intensity, frequency, and selectivity of grazing animals (24, 51). Generally, range managers recognize intensity as the most critical of these factors. Intensity determines how much vegetation remains for maintenance of the plant, soil, wildlife, and water components of range ecosystems. Considerable controversy exists over how grazing intensity should be measured, however.

Methods used to measure grazing intensity are grouped as follows: general reconnaissance, ocular estimate, weight measurement, height measurement, and grazed plant and residue methods. We analyzed these methods in an effort to provide guidelines for rangeland managers and researchers on what methods to use in various situations. Our analysis was restricted to methods involving herbaceous vegetation because grasses and forbs usually, though not always, determine how well soil and water resources are protected.

General reconnaissance

The general reconnaissance method of measuring grazing intensity is based on visual inspection of extensive areas. This method is commonly used by ranchers because of its simplicity and speed. Accuracy depends upon the experience of the observer. Stubble height and leaves remaining on important forage species, the proportion of grazed to ungrazed plants, soil cover, and the pattern of defoliation are among the …