Research and Conservation in Southern Sonora, Mexico
Rancho Santa Bárbara and its Tropical Canyons
Rancho Santa Bárbara is a remote ranch in the Sierra Madre Occidental northeast of Alamos. It is accessible only by a 2-hour drive from Alamos to the end of a four-wheel drive road, then a half-day's hike up a trail. The Alvarez family farms and ranches on a relatively flat bench in the mountainous terrain. The surrounding land is is minimally disturbed.
Two deep, wet canyons at Santa Bárbara are pristine; their ruggedness makes them nearly inacessible to cattle and difficult for humans. Their rims are in the oak woodland community, and their precipitous slopes plunge into the wettest tropical habitat known in Sonora. The vegetation appears to be tropical semideciduous forest; if so it is the northermost limit of this community in North America. Preliminary explorations have documented scores of plant species new to Sonora and several that are yet unidentified. Two tropical orchids (Brassavola cucullata and Cattleya aurantiaca) are among the new records for the state found on Rancho Santa Bárbara.
 Amapa trees (Tabebuia impetiginosa) flowering near Alamos, Feb. 2004. This species ranges from southern Sonora to Brazil where it is known as ipe. The hard wood is highly-valued because it resists rot and termites in tropical conditions for more than a century. Photo: S.A. Meyer |
 Amapa amarilla (Tabebuia chrysantha) is also common in the Alamos region. Photo: G.M. Ferguson; inset: Mark Dimmitt |
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| Along the trail to Rancho Santa Bárbara. Photo: S. A. Meyer Feb. 2004 (very wet winter) | |
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| The horse trail to Rancho Santa Bárbara. Photos: S.A. Meyer Feb. 2004 | |
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| Views from the trail crest down to Rancho Santa Bárbara. Photos: S.A. Meyer Feb. 2004 | |
 Rock corral near Rancho Santa Bárbara. Photo: S.A. Meyer Feb. 2004 |
 Daily life at Rancho Santa Bárbara. Photo: G.M. Ferguson |
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| Two of the houses at Rancho Santa Bárbara. Photo left: S.A. Meyer; right: G.M. Fergsuon | |
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| Aerial views of Arroyo Verde (probably). Photos: Mark Dimmitt | |
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| Arroyo Verde viewed from the ground in May, the middle of the dry season. This and Arroyo Santa Bárbara may qualify as tropical semideciduous forest. Photos: G.M. Ferguson | |
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| Arroyo Santa Bárbara in October, a month after the end of the rainy season. Photos: G. M. Ferguson | |
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| Arroyo Santa Bárbara. There are probably many new species for the state of Sonora to be found in this rugged canyon. Photos: G.M. Ferguson | |
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| Looking into two of the many canyons that incise the mesa at Rancho Santa Bárbara. Right: Two of several species new to science that were recently discovered here: Dasylirion gentryi (narrow spikes) and Hesperaloe tenuifolia (at woman's foot). Photos: G.M. Ferguson | |
 The wet canyons support several epiphytes. Visible here are the bromeliad Tillandsia cretacea (pink spikes) and the orchid Encyclia adenocarpa (dead center). Photo: G.M. Ferguson |
 Some Sonoran native orchids. Two of these are known in the state only from Arroyo Verde: Brassavola cucullata (upper left) and Cattleya aurantiaca (upper right). Stanhopea maculata (lower left) is known in Sonora from a single canyon in the same Mountain range. The lavender Laelia eyermaniana is common in the oaks on the trail to Rancho Santa Bárbara. Photos: Mark Dimmitt |
