Several Mogollon groups clustered within roughly 100 miles east and west of the New Mexico and Arizona border and extended some unknown distance southward into Chihuahua and Sonora. These westernmost groups – with their signature brownware ceramics – give definition to the Mogollon culture, but another group, closely related culturally and called the Jornado Mogollon, spanned another two hundred miles eastward, almost to the Great Plains, and some unknown distance southward, into Chihuahua. The Mogollon groups, widely separated in different environments, progressed at different rates through three basic phases of cultural development.

In the first phase, which began sometime around the start of the first millennium, the western groups probably still accepted agriculture somewhat grudgingly even though it had been around for at least 2000 years. Some lived in rock alcoves or caves. Others, probably extended families of a few dozen people, built small hamlets of scattered lodges atop easily defensible knolls, ridges and bluffs, overlooking their fields. They sometimes erected crude fortified walls to help protect their communities. They may have lived in fear of raids by nomadic bands who still clung to a predominantly hunting and gathering way of life.

The early Mogollon lived in semi-subterranean lodges, or "pithouses," which consisted of excavated holes typically covered by domed roofs. The holes, roughly circular in shape, measured two to five feet deep, with a diameter of 10 to 15 feet. The roofs, made of brush and grass with a thick mud plaster cap, rested either on four upright forked posts set in a square or on a single upright post set in the center and other posts set at the perimeter. A ramped crawlway or a stepped doorway served as an entrance.

On the higher peaks, at elevations from about 9500 to 11,500 feet – the windiest, wettest and coldest environment in the Mogollon region – spruce and fir trees dominate, reaching the timber line and growing in dense stands along the banks of streams and the edges of alpine meadows. Several dozen other plants, including trees in the conifer family and shrubs with edible fruits, also appear in the zone. Annual precipitation ranges from 30 to as much as 90 inches, with winter snow drifts often lasting well into the spring or even early summer.

At 8000 to 9500 feet, the vegetation increases in abundance, with dense stands of dark-green Douglas fir mixed with the white-barked quaking aspen assuming the dominant role. Plants from higher and lower zones sometimes extend arms of growth into this band. Willows line streamsides, and lodgepole pines pioneer areas cleared by fire. Several shade-tolerant shrubs with edible fruits grow within the forest stands. Annual precipitation falls to 25 or 30 inches.

Between 6500 and 8000 feet – the lowest band of true forest in the region – the ponderosa pine and Gambel oak define the character of the plant community. Again, plants from the higher and lower belts wander into this range. About four dozen plants, several with edible fruits, grow only in this region. Annual precipitation declines to 20 to 25 inches.

Between 4500 and 6500 feet – the usually dry and rocky zone which separates the mountain forests from the desert basins – drought-resistant and slow-growing pinyon pine and one-seed and alligator junipers take center stage, forming "dwarf" or "pygmy" forests. Cacti, yuccas, Apache plumes, saltbush, greasewood and numerous other plants from the desert reach up into the zone. In good years, the pinyon pine cones yield an abundance of
nutritious nuts-a crucial food source in prehistoric times