Cholla (Opuntia species) Highly branched cacti. Large species are favorite nest sites for cactus wrens, thrashers and verdins. Packrats use spiny “joints” to armor their nests.

Prickly Pear (Opuntia species) Large, thick, flat pads grow from one another to form branched plant with large, colorful flowers and fruit. Form varies from sprawling to upright, depending on species. Most are spiny. Good escape cover. Those producing juicy fruit in summer are prized by many birds, mammals and some reptiles, including desert tortoise. Javelina eat pads and fruit.

Saguaro (Carnegiea gigantea) Very tall, massive, succulent green trunk with several branches when mature, a single pillar when young. Large white flowers near tips of branches in May and June. Saguaro cactus flower is Arizona's official state flower. Large, juicy red fruit in June and July. Up to 40 or rarely 50 feet tall. Spiny, slow-growing. Takes the place of large tree trunks in the desert for cavity-nesting birds; woodpeckers dig nest cavities in trunk, which are later used by other hole-nesting species. Nectar and pollen eaten by bats and birds; fruits and seeds eaten by many animals. One of the most valuable wildlife plants in the Sonoran Desert.