Forage Quality on the Arizona Strip

Abstract

to her physical state. Poor forage quality can have a significant impact on calf health and vigor, on calf weaning weights, and on mother cow reproductive performance—both calf crop percent and when the calves are born. All of these things hit the rancher directly in the pocketbook. Information on a cow’s nutritional needs has been available for years. But there has been very little information on the major forages available to cattle on the northern Arizona-southern Utah portion of the Colorado Plateau. Samples of major forages were collected monthly over a 3-year period and analyzed for crude protein content (CP), energy content (TDN), and phosphorus (P). During the last year of the study some samples were also analyzed for several important micro-nutrients. It is not possible to display all the data here. Examples from a higher elevation collection site will be used as illustration and our findings will be discussed in general. A complete list of ecological sites and species collected can be found in Table 1. The information gathered during this study will be used to discuss the following points: 1) The general pattern of nutritional quality through the different seasons 2) Any differences between years, and how these differences can be tied to rainfall 3) How cool-season grasses compare to warm-season grasses, and how grasses compare to browse 4) Whether or not there are differences in forage quality between low and high elevations