Big sage, rabbitbrush, and greasewood inhabit the sandy-soiled benches that have a larger groundwater supply. The continuous supply of water adjacent to both the Green and Colorado rivers gives rise to communities of cottonwood, willow, and tamarisk. Even the soil has special significance. What may first appear to be just a blackish-gray, lumpy crust is actually a microscopic plant community made up of cyanobacteria, lichens, fungi, and algae. Called cryptobiotic soil, it grows among sterile grains of sand, binding them together to retard erosion and adding nutrients that will help larger plants survive.
Cryptobiotic soil is very fragile.
A footstep can destroy it, and decades will pass before it can reestablish itself. So remember to stay only on designated trails and roads. As in the plant kingdom, animal life at Canyonlands is diverse. From tiny biting midges to the rarely seen bighorn sheep, animals in the park have adapted to a wide range of climatic conditions. Some are fairly stationary, while others move from one microclimate to another in search of food, shelter, and refuge from predators.