Thousands of plants have adapted to the hot desert environment. Some go dormant during the hot periods and wake up when water becomes available; others grow very long roots to get down to water deep under the surface. These kinds of plants that adapt by altering their physical structure are called xerophytes and they have not only adapted to the desert, the desert has adapted to them so that they are truly integrated into the ecosystem.
The barrel cactus (Ferocactus wislizeni) can grow to be from 1.5 to 3.3 m (5 to 11 feet) tall. It has parallel ridges that extend from top to bottom and are covered with very sharp, 7.5 to 10 cm (3 to 4 inch) spines and blooms either yellow-green or red flowers at the top of the plant. Barrel cactus contains water and is edible; it can be stewed like cabbage and can be made into "cactus candy."
Brittle bush (Encelia farinose) is a deciduous shrub that grows between 60 cm and 1.5 m (2 to 5 feet) tall. The leaves are 2.5 to 10 cm (1 to 4 inches) long, have serrated edges and are covered with tiny hairs that make the leaves appear grey-green. These hairs capture moisture from the air and act as a layer of insulation from the heat and cold. Their yellow flowers are on long, bare stems that rise above the plant by about 8 cm (several inches). The plant secretes a clear resin that can be used as glue, toothpaste or gum. The resin can also be applied to skin wounds to relieve pain.
Jumping cholla (Opuntia bigelovii) is sometimes called the "teddy bear cholla." It has short, fuzzy branches that, from a distance, look like fuzzy teddy bear arms, however, they are actually a plethora of silvery spines that can "jump" off the plant and into a passerby's leg. It blooms greenish-yellow flowers that are about 3.7 cm (1 1/2 inches) in diameter.
The Mojave aster (Xylorhiza tortifolia) is a perennial that grows to be about 75 cm (30 inches) tall with silver-green, hairy leaves and as many as 20 lavender to purple flowers that can be up to 5 cm (2 inches) in diameter. After blooming the plant dies back. After wet winters, black caterpillars with grey and orange stripes will cover the foliage, feeding on the plant's nectar before turning into bright orange butterflies.
Scarlet hedge-nettle (Stachys coccinea) is an erect, leafy plant with scarlet flower clusters that grows to be up to 90 cm (3 feet) tall. Blooms are tubular with a single-lobe at the end of the tube over a tri-lobe lower lip. It is known to attract bees, hummingbirds and butterflies. The leaves are fragrant, triangular shaped and are covered with tiny, non-stinging hairs. They are about 3 cm (1 1/4 inches) long with serrated edges.
Desert beard tongue
Desert beard tongue (Penstemon pseudospectabillis) is an evergreen and ever-blooming perennial with long spikes of pink to purple flowers and large grey-green leaves. It grows to a height of 60 cm to 1.2 m (2 to 4 feet). Its blooms are long and tubular, resembling a snapdragon's. Mature plants will have as many as 12 stems of flowers protruding from its base.