Arizona is a diverse state, rich in desert plant life, at a multitude of elevations and supporting an important ecological wilderness that many miss at first glance.
The state of Arizona is often misunderstood with regard to its plant ecology; with elevations ranging from 141 ft at the Basin and Range region of the Sonoran Desert to 12,633 ft at Humphreys Peak on the San Francisco Plateau, just south of the Grand Canyon. Arizona has perhaps the most rare and unusual plants in the United States. From traditional cacti to desert wild flowers, each contributes to the survival of the desert.
Native plants help prevent erosion of an area, shade the desert floor, reflect the heat of urban cities and provide food and shelter for a rich diversity of desert wildlife. Plants indigenous to the region survive better than non-native plants as they have the ability to survive long periods of time without water in the hot desert sun. Plants at higher and cooler climes, such as those in the Grand Canyon region, have the ability to survive harsh winter snow.
The Native Plant Ordinance of Arizona
The Sonoran desert extends from Southern Arizona and California into Mexico; it has the most powerful plant ecology of the four North American deserts (Mojave, Great Basin and Chihuahuan being the others). The reason for this is that the Sonoran desert has differing temperatures, rainfall and elevations resulting in a variety of vegetation and wildlife.
In light of this knowledge, the City of Scottsdale in Arizona has introduced the Native Plant Ordinance to protect indigenous plants from urban developments. Many plants found within the Scottsdale area are unique to the region and thus contribute greatly to the economic future of the community, as well as being aesthetically pleasing. The Native Plant Ordinance protects thousands of native plants from urban construction and has been the blueprint for similar legislation across the United States.
Protection of Native Plants
Desert cacti and trees can take years to reach maturity and landmarks of the desert south west such as the Saguaro can not be easily replaced by nursery-grown plants. It is estimated that 250,000 protected native plants have been saved from destruction since the City of Scottsdale implemented the Native Plant Ordinance in the 1980’s.
Examples of protected native plants within Arizona include Saguaro (Carnegieca gigantea), Ocotillo (Ferocatus species), Desert Willow (Chilopsis linearis), Juniper (Juniperous species), Cottonwood (Populus fremontii), Mesquite (Prosopis species), Arizona Rose Wood (Vauquelinea Californica) and Cat Claw (Acacia greggii). The Native Plant Ordinance stipulates that protected cacti are over three feet in height. Native plant permits must be applied for if a project may disturb the environment within the Ordinance’s stipulations.
Arboretums of Arizona
There are a number of arboretums and botanic gardens of Arizona which have been established to educate people on the importance of native plants to the environment. The arboretum at Flagstaff specifically highlights the plant communities of the Colorado Plateau. The Desert Botanical Gardens is dedicated to the study and conservation of arid land plants throughout the world. Tucson Botanical Gardens has grown from its simple foundation in 1964 to an important cultural and educational resource.
If indigenous plants are to survive and sustain the ecology of their environment, it is essential that people are aware of and understand the importance of native plants in a particular area. Desert plants support one of the harshest environments of the planet and their survival depends on both environmental protection and an understanding of plant ecology.