Desert Flora : How They Survive The Harsh Conditions

Life in the high desert hinterlands can be cruel. High temperatures in the summer, little water and sparse shade make it hard on animals and people. But several members of the plant world have adapted to these harsh conditions and even thrive in them. Their superficial root systems, water storage capabilities and waxy leaves allow them to survive through high and low extremes. In Lancaster, for example, the average high temperature is 98 degrees in July. In January, the average low is 29 degrees. Here’s a look at some of the plants in and around the Antelope Valley, that make their home in the western Mojave Desert.

Beavertail Cactus ( Opuntia basilaris )

Only one of two native cacti to the western Mojave Desert, the beavertail cactus--with its distinctive magenta or white flowers--gets its name from the shape of its pads. Water is stored in the pads and it reproduces with seeds. The stomata, surface pores which carry out photosynthesis, open only at night when humidity is higher and the plant is less likely to lose precious water. Its skin is waxy to reduce water loss, but fleshy inside. Instead of long needles or leaves, the beavertail has small bunches of short spines that reduce water loss. It grows 6 to 12 inches high and 1 to 6 feet in diameter.

Joshua Tree ( Yucca brevifolia )

Rigid leaves covered by a waxy surface help the Joshua tree survive in the desert by being able to resist wilting and water loss. Its widespread roots are about 3 feet deep. Water is stored in its trunk and leaves. The plant is pollinated mainly by the yucca moth and reproduction of the plant occurs when its black, flat seeds are scattered in the wind or when underground stems sprout near the parent tree. Joshua trees don’t flower every spring. This flowering is also tied to weather. Joshua trees produce few flowers after a warm winter, more after a cold one. A large Joshua will be about 30 feet tall, although there is one 58 feet tall in Lancaster that is estimated to be 1,000 years old.

Bigelow’s Coreopsis ( Coreopsis bigelovii )

While Joshua trees and cacti grow very slowly, this wildflower survives in the desert by growing quickly. The reason: Its leaves can only store small amounts of water. An annual, it germinates in the fall, blooms in the spring and dies off in summer, sitting out the hottest months. Some years are better than others for the Bigelow’s coreopsis. The seeds will only germinate when soil temperatures are low and moisture content of the soil is high. Found more commonly in the western Mojave Desert, they grow 6 inches to 2 feet tall.

Rain Catchers

When it doesn’t rain very often, water doesn’t have a chance to soak deep into the soil. As a result, cacti have shallow, wide-ranging root systems allow them to grab as much rainfall as possible. The roots have tiny hairs that help them collect water. The plants often grow spaced out because of stiff water competition below the surface.

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Sources: “The Way Nature Works;” “Roadside Plants of Southern California,” UC Riverside Department of Botany and Plant Sciences; California Department of Fish and Game; and plant author Milt Stark. Researched by STEPHANIE STASSEL / Los Angeles Times