|Desert Mistletoe (Phoradendron californicum)
This parasitic plant, which grows mainly in deserts and foothills below 4000 feet in elevation, is also known as "the slow killer." It infects common southwestern trees and shrubs including mesquite, paloverde, ironwood and acacia. Although plants may survive for a long time while supporting the parasite, the roots of Desert Mistletoe invade the bark and sap of the host plant, depriving it of water and nutrients and weakening the plant overall.
Mistletoe appears in trees as several large masses or clumps, sometimes mistaken for nests. The mistletoe in the photo above appears at the bottom of a mesquite, but many times the clumps are located higher up in the branches. The stems are scalelike and the fruits are pinkish berries. The photo below shows the damage done to the tree at the attachment site. Birds such as the Phainopepla are attracted by the berries and often spread the seeds from one plant to another through their digestive systems.