Northwest of the Valley, amid desert mountains marked with ancient petroglyphs, a group of Arizona cowboys is returning to natural ranching techniques used by their counterparts more than 100 years ago.

Past Wickenburg, on the Yavapai County border, two mid-sized cattle ranches are thriving by catering to a niche market of health-conscious consumers.

Date Creek Ranch and O X Ranch are raising grass-fed cows whose beef is marketed as being leaner than the grain-fed product that occupies most store shelves. Cattle ranching remains a major economic activity in the far Northwest Valley. Though it once ruled Arizona and much of Maricopa County - including the West Valley - longtime ranchers have continually moved further out on the state's rural fringes as developers' projects sweep across range lands closer in.

Debate continues over the actual health benefits of grain-fed versus so-called "natural" or "organic" grass-fed beef. But O X Ranch General Manager Pat Browning said he believes that his efforts are best for the animals and the land.

The techniques used to produce grass-fed beef incorporate environmentally friendly practices, many of which were used by ranchers long before the popularization of mass meat production.

"We cowboys are environmentalists in the first sense, we have to be," Browning said. "Preserving the quality of this land is paramount to our survival."

For 12 years, O X Ranch was a fledgling operation owned by a family living in central Phoenix. The family hired Browning about five years ago, hoping to differentiate the business by selling what they felt would be a healthier product. Browning is converting the ranch so that it produces beef that meets three kinds of USDA marketing standards: natural, grass-fed and organic. Along the way he has made several environmental changes to the ranch so that the end product meets USDA classification standards.

Some of those changes, such as rotational grazing and natural irrigation techniques, date back to the late 1800s. Rotational grazing requires cowboys to rotate the pastures on which cattle graze each season. The technique saves wild plants from being trampled and allows ecosystems to thrive.

The O X Ranch also sits on a natural spring used to irrigate cattle pastures. Date Creek Ranch uses similar tactics.

On modern mass-production ranches, cows often are raised in confined pens and fed high-calorie grains to speed their growth, Browning said.

Though smaller ranches formerly used the same techniques, many have been forced to make changes because the largest ranches were the only ones that remained profitable amid rapid development, said Ed Hermes, a spokesman with the Arizona Department of Agriculture.

As more small and mid-sized ranches are sold off, the survivors are those converting to operations similar to O X and Date Creek, Hermes said.

"Smaller guys go to these niche markets to try to stay alive and make enough money," Hermes said. "They have done that by adding value to their cattle, going straight to the consumer and going either organic or all natural."