Three experiments were conducted to examine restoration of disturbed land in Arizona. The first experiment attempted to revegetate abandoned farmland by direct seeding native seeds and using various soil preparation techniques, amendments, and weeding of Salsola iberica. Only irrigation and weeding had a significant effect on seed germination and canopy cover. Irrigation increased plant cover on plots, but weeds dominated the cover. A seedbank study conducted near the end of the second growing season found the soil was dominated by weeds and contained few viable native seeds. The results illustrate the difficulty of establishing native plants on abandoned desert farmland due to the dominance of weedy species, the presence of salts in the soil, and the lack of adequate soil moisture.
Restoration of disturbed desert ecosystems to a long-term, sustainable, and aesthetically pleasing landscape in a cost-effective manner is challenging and success is rarely, if ever, guaranteed. Many revegetation techniques, such as broadcast seeding, transplanting, applying amendments, and irrigating, have been tested and have achieved various results. Revegetation of abandoned farmland is challenging because the soil is often compacted and saline, natural contours in the landscape have been altered, and the seedbank lacks native seeds. Reclamation of mine tailings poses a greater problem because tailings are often phytotoxic due to low pH and/ or high metal concentrations. Many factors contribute to the success of a restoration project; however, water availability is a critical factor in arid and semi-arid environments.