BL / ENVS 448 Plant Biodiversity and Ecology Plant Communities of the Rocky Mountains

What are plant communities? Often defined by major plant species / types Temperature and precipitation prevail Altitude determines the above Several types in Colorado From lowest (and hottest) to highest (and coldest)

Desert and semi-desert Mainly canyon country in the western part of the state Less than 14 inches of rainfall 4,000 to 6,500 feet in elevation Lower areas dominated by shrubs like rabbitbrush and sagebrush Higher areas dominated by Pinyon Pine and Juniper

Rabbit brush and Pinyon Pine

Moving on up - Grasslands Dominated by grasses 3,500 to 6,500 feet More precipitation (about 20 inches) Eastern third of Colorado Can still find some sagebrush and rabbitbrush and cactus, but many more mixed grasses Tall grass and short grass in Colorado

Grasslands

Bouteloua sp. Grasslands

Big Will and Will J. in tallgrass

Prickly Pear amongst the grasses

Foothills Includes mesa tops 6,500 to 8,500 feet Ponderosa pine, still some pinyon and juniper Oak thickets (we only have one Gambel’s) Mountain mahogany 14 to 25 inches of precipitation

Foothills

Inspiration Point – sagebrush and P.J.

Will J. enjoying the foothills

Bobcat in the foothills

Montane Forest Mixed conifer and aspen (most wide ranging tree in U.S.) 8,000 to 10,000 feet Understory vegetation is mostly shrubs Willow shrubs in riparian areas inches of precipitation ¼ to ½ as snowfall

Montane Forests

Pentaphylloides floribunda aka Rocky Mountain Cinquefoil

Penstemon whippleanus

Aquilegia caerulea

Subalpine Thick spruce/fir forests Aspens only in lower elevation here inches of precipitation a year Last zone before alpine

Hard at work in Breckenridge

More hard work in the montane /subalpine

Mertensia ciliata mountain bluebell

Castilleja rhexifolia X miniata Indian paintbrush

Chaemerion danielsii

Alpine Alpine tundra (not arctic tundra) Dwarf shrubs, herbs, and cushion plants Above treeline (about 11,500 feet in CO) inches of moisture Most as snowfall

Above the trees

Big horn sheep

Eritrichium aretoides alpine forget-me-not

Gentiana parryi - Parry’s gentian

Silene acaulis – moss campion

TROPICAL ALPINE Azorella compacta