NPS/John Spence

Desert dandelion (Maliacothrix glabrata)

Glen Canyon National Recreation Area (NRA) has highly diverse vegetation typical of the Colorado Plateau region. Vegetation communities are affected by variations in soil, water availability, substrate type, and elevation. In the Glen Canyon area, low growing shrubs on clay badlands contrast sharply with lush hanging gardens fed by springs which grow on cliff walls. Green strips of riparian zones wind through desert slopes and past sheer cliffs. Vegetation communities create habitat for wildlife by providing important water and food sources.

The plants of the Colorado Plateau have developed adaptations crucial to survival in the arid conditions of the desert. The seeds of annual plants can remain dormant for years, waiting to germinate during wet seasons. Over 850 species of vascular plants have been reported in Glen Canyon NRA. Vascular plants include trees, shrubs, grasses, ferns, and flowering plants. Spectacular wildflower displays carpet the area in spring, especially in April and May, after a wet winter, and occasionally after summer monsoons. In spring, the yellow blooms of the desert dandelion (Maliacothrix glabrata) are common in sandy habitats, while clay barrens support spectacular displays of Palmer’s cleomella (Cleomella palmeriana) and desert trumpet (Eriogonum inflatum). Species like purple aster (Machaeranthera canescens) and narrowleaf pectis (Pectis angustigfolia) flower after the summer monsoons. The showy blossoms of these wildflowers attract numerous species of pollinators, including native bees, butterflies and beetles. In addition to vascular plants, a variety of moss, liverwort and lichen species are also found, while algae are common in springs and streams and ponds.

NPS/John Spence

Showy rushpink

Glen Canyon NRA is home to 20 plant species that are considered rare by the states of Utah and Arizona, though some of these plants are common elsewhere in the United States. Several species which are extremely rare and especially vulnerable to extinction are found in the Glen Canyon area: Copper Canyon milkvetch (Astrgalus cutleri). alcove rock-daisy (Perityle specuicola), and kachina daisy (Erigeron kachinensis). Jones cycladenia (Cycladenia jonesii) is listed as federally threatened. Hanging gardens are especially diverse and are home to 10 of the 40 Colorado Plateau endemic species found in Glen Canyon NRA.
 
Nonnative species have been introduced to the regional ecosystems by human activities or have spread into the area from adjacent infested regions and threaten native species. Currently about 11% of the plants in Glen Canyon NRA are nonnative and can pose threats to sensitive habitats including hanging gardens and other native plant communities. Tamarisk (salt cedar, Tamarix chinensis), Russian olive (Elaeagnus angustifolia), and ravenna grass (Saccharum ravennae) are widespread and outcompete native species for habitat.

For more in depth information on the plants and vegetation communities of Glen Canyon NRA, explore Vascular Plants and Natural Features and Ecosystems pages. A checklist of the vascular plants found in Glen Canyon NRA is available here.