Acer negundo
Actaea rubra green
Actaea rubra (red)
Aerial view of Bog D
Agropyron spicatum
Alisma subcordatum
Allium tricoccum
Alpine Clover Colorado Rockies
Alpine Plant Colorado Rockies
Alpine Plant Colorado Rocky Mountains
Alpine Plant (Geum Rossi) Colorado Rocky Mountains
Alpine Tundra and Lake near Timberline Colorado Rockies
Alpine Tundra Colorado Rocky Mountains
Alpine tundra in Colorado
Alpine Tundra near Niwot Ridge Colorado Rocky Mountains
Alpine Tundra Plant (Erysimum nivale) Colorado
Alpine Tundra Plant (Lloydia cerotina) Colorado Rockies
Alpine Tundra Plant Rocky Mountain Colorado
Alpine vegetation
Alpine Willow Rocky Mountains of Colorado
Ambrosia trifida
Amel alnifolia
Amorpha canescens
Ancient Shoreline Marked by Exposed Rocks
Andrews Glacier
Andrews Glacier and Lake Colorado Rocky Mountains
Andrews Glacier and Valley Rocky Mountains Colorado
Andrews Glacier Colorado Rocky Mountains
Andropogon gerardi
Andropogon gerardi
Anemone cylindrica
Anemone patens
Anemone patens
Anemone patens
Anemone patens
Apocynum sibericum
Aquilegia canadensis
Aquilegia canadensis
Aquilegia canadensis
Aquilegia canadensis
Arctic and Alpine Valuable Plant for Science
Argemone
Arisaema atrorubens
Arisaema atrorubens
Arisaema atrorubens
Arisaema atrorubens
Arisaema atrorubens
Arisaema atrorubens
Asclepias syriaca
Asclepias verticillata
Ash canopy in the Painted Woods
Aspen trees in Colorado
Astrag caryocarpus
Badlands National Park
Badlands National Park
Badlands National Park
Badlands National Park
Badlands National Park
Badlands National Park
Barren, Rocky Slope Alpine Colorado Rockies
Beaver dam
Beaver dam
Beckmannia syzigachne
Bill Lauenroth and Jerry Van Amburg conducting research
Black Sedge Alpine Colorado Rockies
Bouteloua curtipendula
Bristlecone Pine
Bristlecone Pine Krummholz James Peak, Colorado
Bristlecone Pine Krummholz James Peak, Colorado
Bristlecone Pine Krummholz James Peak, Colorado
Bristlecone Pine Krummholz on James Peak Colorado
Bristlecone Pine near Timberline James Peak, Colorado
Bromus jap and Buchloe dacty
Buffalo River Forest
Buffalo River Forest
Buttercup Alpine Colorado Rockies
Buttercup Through Snow, Rocky Mountain National Park
Buttercups in Melting Snow, Colorado
Calochortus nuttallii
Calochortus nuttallii
Caltha palustris
Caltha palustris
Caltha palustris
Caltha palustris
Caltha palustris
Campground near Estes Park, Colorado
Carter Johnson at Sica Hollow State Park in South Dakota
Carter Johnson Doctorate Field Research
Castilleja sessiliflora
Cave Hills in South Dakota
Celastrus scandens
Chrysopsis villosa
Cicada
Cirsium undulatum
Clearing at Garrison Reach, North Dakota
Cleome serrulata
Close-up of Bristlecones Pine Krummholz
Colorado Rockies
Colorado Rockies
Colorado Rockies