Chapter 8: Colorado Plateau State Highway 141, Dove Creek to Naturita

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1 State Highway 141 Dove Creek to (61 miles) Summary: Highway 141 heads north from US Highway 491 about two miles northwest of the town of Dove Creek. Initially, the highway runs through gently rolling farming country much like that between the Utah state line and Cortez. A bit later, the highway crosses on to sandstone bedrock and enters the canyon country. The highway descends and crosses the Dolores River at Slickrock then runs across Disappointment Valley, Big Gypsum Valley, and finally Dry Creek Basin on its way to. Near MP 1, fields of pinto beans appear along the highway. Small islands of sagebrush shrubland and piñon-juniper woodland punctuate the cultivated land (Fig ). Why are these islands here? Probably the soils in these areas are too rocky to cultivate. The native vegetation types in this area are sagebrush shrubland, which mostly occupied ground that is now cultivated, and piñon-juniper woodland, which mostly occupies the rockier sites. As is evident here, sagebrush and piñon-juniper woodland can intermingle depending on local soil and bedrock conditions. Fig : Looking northeast at a field of pinto beans; near MP 1 Reading the Landscapes of Colorado 1

2 The farming country extends about 8 miles north of US Highway 491 to about the Dolores County San Miguel County line. Then the land becomes rockier and piñon-juniper woodland predominates with small areas of cultivated land (Fig ). Fig : Looking east across a pasture toward piñon-juniper woodland; near MP 14 The La Sal Mountains in Utah are visible to the distance to the northwest from a vantage point another mile down the highway. Sagebrush shrubland and western slope grassland are present here on areas with deeper, finer-textures soils, with piñon-juniper woodland on rockier areas in the distance. The highway reaches the edge of the sandstone bedrock in another two miles near MP 17. The view of the canyon country to the north is a dramatic contrast to the farm land farther to the south (Fig ). Flatlying layers of sandstone with minimal soil support piñon-juniper woodland except on outcrops of massive sandstone. Reading the Landscapes of Colorado 2

3 Fig : Looking northeast across piñon-juniper woodland toward the La Sal Mountains; near MP 17 photo DSC_0342.NEF (Sept 11) A few miles further, the highway crosses the Dolores River at Slickrock. You may see vehicles parked near the bridge, because this is a major take-out and put-in point for rafters on the Dolores. The float from Slickrock to Bedrock is one of the premier, multi-day river trips in the canyon country. Although the river may not look that promising, especially late in the summer, river otters have been successfully re-introduced to the Dolores River. Otters were extirpated from Colorado in the early 1900s but have been re-introduced at several locations around the state since The otters in the Dolores River thrive on the abundant crayfish populations. The highway follows the Dolores River for about a mile then turns north, then southeast then east as it runs across Disappointment Valley. The bedrock underlying the floor of Disappointment Valley is Mancos shale. In drier areas, soils that develop from Mancos shale are salty and can support only sparse vegetation consisting of salt-tolerant plant species including saltbush species. Here (and in Dry Creek Basin about 20 miles farther down the highway), there is evidently enough precipitation to Reading the Landscapes of Colorado 3

4 leach the salts below the root zone of the plants in the Western Slope grassland. The dominant species in Fig is galletagrass, a very common species on clay soils in southern Colorado and New Mexico. This is BLM land that is leased for livestock grazing, primarily during the dormant season. Fig : Looking east across Western Slope grassland in Disappointment Valley; near MP 32 photo DSC_0350.NEF (Sept 11) In 7 miles, the highway crosses a low pass and runs across Big Gypsum Valley for about 5 miles. The valley has a variety of vegetation types including Western Slope grassland, saline bottomland shrubland dominated by greasewood, and piñon-juniper woodland on the rocky slopes (Fig ). Reading the Landscapes of Colorado 4

5 Fig : Looking north across Big Gypsum Valley at mosaic of grassland, shrubland and woodland; near MP 36 photo DSC_0362.NEF (Sept 11) The highway runs through a barely recognizable pass into Dry Creek Basin. In contrast to Disappointment Valley and Big Gypsum Valley, the floor of Dry Creek Basin is dominated by sagebrush shrubland. This part of Dry Creek Basin is somewhat wetter (about 17 inches of annual precipitation) than Disappointment Valley and Big Gypsum Valley (about 15 inches annually), thus sagebrush has replaced more droughttolerant plant species. The Dry Creek Basin State Wildlife Area consists of about 13,000 acres of land that is open to the public for hunting, hiking, and wildlife viewing. The understory of the stand of sagebrush shrubland near MP 43 is dominated by crested wheatgrass (Fig ). This species has been imported from Asia where it evolved under grazing by large mammals. Thus, it is pre-adapted to tolerate cattle grazing in the US, especially during the spring and early summer. Crested wheatgrass provides excellent early-season forage for cattle and is widely planted as part of rangeland re-seeding projects in drier areas of the western US. The mesas in the distance east of MP 43 are covered with piñon-juniper woodland. Many years ago, the side of the mesa to the right in Fig failed and Reading the Landscapes of Colorado 5

6 slid out on to the valley floor. The material has since been colonized by piñon-juniper woodland. Fig : Looking east across sagebrush shrubland at land slide on distant mesa in Dry Creek Basin; near MP 43 photo DSC_0372.NEF (Sept 11) Reading the Landscapes of Colorado 6