Low Income Urban Forestry Program in Tucson, Arizona, USA

Tucson is located in the Sonoran Desert, 117 km north of the US-Mexico border. The borderland region is an area experiencing increased temperatures and changing precipitation patterns caused by the combustion of greenhouse gases. Planting drought-tolerant trees to provide cooling shade has been an important mitigation strategy for Tucson and other arid cities. From 2007 to 2013, the Sonora Environmental Research Institute, Inc. (SERI) collaborated with Trees for Tucson (TFT) to distribute drought-resistant trees to low income families in south metropolitan Tucson. The Pima Association of Governments has found that this area has significantly less green spaces than other areas of Tucson. SERI conducted an extensive bilingual community outreach to recruit families, and presented tree stewardship information to families in both English and Spanish. Chilean mesquite (Prosopis chilensis and Prosopis chilensis hybrid), red push pistache (Atlantica X Integerrima), and blue palo verde (Parkinsonia florida) had the highest survival rates while willow acacia (Acacia salicina) and sweet acacia (Acacia farnesiana) had the lowest survival rates. Acacia salicina is less cold tolerant, and a severe frost in February of 2011 may have contributed to its higher mortality