Ecology along the Frontier Pathways Byway

A Diversity of Plants and Animals

The geology of the landscape greatly influences the plants and animals along the Frontier Pathways Scenic and Historic Byway. The low plains, wet valleys and rugged mountaintops all hold their own natural communities and western species are richly represented along the byway.

Biologists use the term life zone to describe plant and animal communities that change with elevation. Both temperature and precipitation greatly influence these communities. The temperature drops about 3.5 with each 1000-foot gain in elevation. In addition, precipitation increases with elevation. The aptly named Wet Mountains sometimes receive over 20 feet of snow in the winter. The different climates and communities make driving from Pueblo to Westcliffe comparable to driving from Mexico to Montana.

Another factor that influences the plant communities is the aspect, or slope, of hills. If you are hiking, you’ll notice that north-facing slopes are shadier, cooler and more moist than south-facing slopes. Therefore, north-facing slopes generally bear thicker forests. The sunny, dry south-facing slopes may lack trees, or the trees may be more widely spaced. This is easily observed on your travel through the Hardscrabble Canyon.

Pueblo lies in the plant life zone that is characterized by grasses, prairie dogs, rattlesnakes and native trees that grow only near water. The area receives just 12 inches of precipitation a year. As you head west from Pueblo on Highway 96, a rise in elevation brings more moisture. The lower part foot hills life zone contains pinyon pines and juniper trees. Higher up you’ll see Gambel (sometimes called scrub oa-k), ponderosa pine, scrub jays and mule deer. In the mountain life zone, watch for aspen, Douglas fir, elk and the blackcrested Steller’s jay.

Looking up from the Bigelow and Hardscrabble Divides (9,400’ elevation), travelers can see  the sub alpine life zone. Here, spire-like Engelmann spruce and sub alpine fir shed heavy loads of snow. In the Sangres, the upper limit of tree growth, or tree is usually around 11,500 feet in elevation. Above this elevation in the alpine the life zone, strong, drying wind and cool temperatures limit vegetation to low lying herbaceous plants. In the summertime, hikers are treated to a carpet of colorful and fragrant alpine tundra wildflowers.