DESCRIPTION: Tree to 30-40' high. Bark bluish-green and smooth. Spines are small (0.25"), green, and straight. Leaves are bipinnately compound, with three or fewer secondary leaflets per primary leaflet (versus four or more in Foothills Paloverde). Flowers are bright yellow and 5-petaled (all petals are bright yellow in contrast to Foothills Paloverde that has its largest petal white). Flowers in spring (April), usually before Foothills Paloverde in the same area. Fruit is a flat pod starting green and turning yellow. Fabaceae (Legume) Family.
NATURAL HISTORY: The Blue and Foothills Paloverdes are Arizona's State Trees. Paloverde means "green stick" in Spanish, referring to the smooth, green bark in which photosynthesis takes place. This allows the tree to drop its leaves (drought deciduous) to conserve water, yet still photosynthesize. Compared to Foothills Paloverde, Blue Paloverdes need more water thus tend to be more restricted to washes and roadsides. The seeds are very hard, thus are not as easily eaten by humans, but you should hear what it sounds like when Javelina crunch up the seeds with their strong teeth. The seeds need to be scarified (abraded, as occurs in flash floods or digestive tracts) or weathered underground a few years before germination occurs. The flowers are an important source of nectar and pollen for many species of solitary bees, as well as other insects.