A 1-year study was conducted to measure the forage volume necessary to maintain a goat herd in the semiarid zone of Mexico in terms of economic feasibility and seasonal grazing to conserve range land. The average weight of the adult females was 53 ± 5 kg and yearlings weighed 40 ± 3 kg at first kidding. Average milk production was 400 ± 67 kg in 210 days. A concentrate of 2.9 Mcal ME and 16% CP was offered twice a day. Average voluntary feed intake was 1.880 kg DM day−1 with an annual total of 686.3 kg; of those, 248.7 kg DM was provided by alfalfa hay from a forage bank corresponding to 36.2% of the total feed intake; 210.9 kg or 30.7% of the diet was concentrate and 226.6 kg or 33.0% was from the range land (grasses, shrubs and tree leaves). Alfalfa hay varied greatly in price during the year, being cheapest during October to December. Therefore to make most economic use of alfalfa as a forage bank for the rest of the year total supply of alfalfa had to be purchased during that time. Under the system of this study, alfalfa use was greatest during the time of zero grazing which was from February to April to avoid overgrazing and maintain biosustainability of the range land. From July through September grazing was the main source of nutrient supply because of the previous rain, thereby saving alfalfa hay and supplement feeding which diminished cost of production.