click image to zoomColorado’s Sangre de Cristo Range forms a backdrop for the San Isabel Ranch. Sara Shields (center-right) shares ranch responsibilities with husband Mike, mother Bet Kettle and son Brandt. In many ways, life on the San Isabel Ranch, in southern Colorado at the base of the Sangre de Cristo Mountains, remains as it was over 100 years ago. Owners Sara Shields and her husband Mike use cell phones and computerized records, but they still rise before the sun, saddle their horses and spend the day caring for their cattle and the land that sustains them.
Shields’ great-grandfather started the ranch in 1872, initially focusing on securing water resources in the Wet Mountain Valley and growing hay for the horses and mules that accompanied the influx of miners to the area. Eventually, her grandfather began raising sheep to utilize unsold forage, and later switched to cattle.
Her father, veterinarian Ben Kettle, shifted the ranch to purebred Hereford breeding, and today the operation has evolved to specialize in bred replacement heifers along with commercial feeder calves and commercial hay production.
For generations, the family has viewed land stewardship, water conservation and community involvement as critical priorities and totally compatible with their cattle business. In 2007, the family received the prestigious Leopold Conservation Award, presented by the Wisconsin-based Sand County Foundation. The award is named for conservationist Aldo Leopold, whose book A Sand County Almanac pioneered concepts of land stewardship.
Shields says the ranch needs about 12 acres of land per head to maintain good forage productivity. To maintain that productivity, the family has focused on range management and timed, rotational grazing.
The family has shifted part of the herd to a fall-calving system as a means of diversifying its marketing opportunities for bred replacement heifers and feeder steers, and to optimize forage utilization.
The spring-calving cow herd is primarily straight-bred Hereford, with some Hereford-Red Angus crossbred cows. The family breeds first-calf heifers back to Red Angus bulls. The spring-calving herd is bred beginning in July for a 53-day calving season in April and May.
The fall-calving cow herd is primarily Angus-Red Angus crossbred cows, which they mostly breed back to Red Angus bulls, although some customers request heifers bred to Hereford bulls. The fall-calving herd calves around Sept. 1.
The goal for both herds, Shields says, is to produce replacement females with excellent calving ease, maternal traits and efficiency in mountain rangeland conditions. “We use the same replacement heifers in our herd as the ones we sell,” Shields says. Most customers are working to improve the genetic makeup of their cow herds while avoiding the labor and expense of raising all their own replacement heifers. Many, she says, retain the heifer calves from the replacements they purchase, which Shields says is a gratifying sign of their confidence in their genetic merit.
Focusing on fertility and nutrition, the ranch has achieved excellent results, with 70 percent of the cow herd calving within the first 21 days and 90 percent within the first 45 days of the calving season over the past 10 years. The tight calving season reduces labor at calving time and provides value to customers who purchase replacement heifers.