The best ground cover for Tucson is the native Creosote Bush. With proper care a Creosote Bush may live to be 12,000 years of age.
The largest of our native trees the Fremont Cottonwood, Goodding Willow, Velvet Ash, Arizona Black Walnut, Western Soapberry, Netleaf Hackberry, Black Elderberry, Velvet and Screwbean Mesquites and Catclaw Acacia grew along our rivers and major washes. That’s where they grew and that’s where they need to be planted.
Velvet Mesquite, Blue Palo Verde, Desert Ironwood, Foothills Paloverde, Desert Hackberry, Whitethorn Acacia, Greythorn, Longleaf Joint-fir, Kearney Snakewood and Limberbush grew along the desert washes and where conditions were right, on the desert flats along with an occasional Soaptree Yucca, Saguaro and other cacti.
For the most part though the Tucson basin was covered with the yellow flowered, fuzzy seeded (forming a Thanksgiving/Christmas halo), forecaster of the rains, the lovely and fragrant Creosote Bush.
Disclaimer: As submitted to the Arizona Daily Star.