When I first moved out to the desert, I was taken by surprise by the amount and variety of plant life that could survive in such a hot and dry environment. It just seemed impossible, unless the plants had roots that went all the way to China.

Every time I went hiking, I saw something new or unusual. If I had the opportunity to go hiking within a couple days after a rain, be it a heavy or light rain, the desert seemed to go into overdrive with growth; small, green leaves sprouting from what looked to be dead branches; many different flowers popping out of what used to be a sandy, barren ground; even some of the bushes would be sporting small flowers. On hot days, certain plants would become shiny and oily, which would make me think they were some kind of poison ivy-like plant.

Hiking gave me a lot of time to think about all of what I was seeing and to try to come up with possible answers to why these plants did what they did and how it helped their survival.

I would stop occasionally to examine certain leaves that changed as it became hotter, or leaves that seemed to have a whitish tinge to them. I found that some leaves had fine hairs on the top of the leaf. Other leaves had a waxy coating that glistened during the heat of the day, whereas other leaves would be curled inward, which made me think these plants were about to lose their fight for survival.

I was content to continue coming up with different theories as to why plants were able to survive until one day, while channel-surfing the television (alas, a bad habit of mine), I stumbled upon a program talking about plant adaptation in the desert. I was captivated because they explained many of my observations and questions.

Plant adaptation is how plants change to survive their environment – in this case, the drying effects of the desert. These plants didn’t just modify physical characteristics, but also their behavioral mechanisms. I know. What? Behavioral mechanisms? I’ll get to that in a moment.

For those of you who like to impress people with your vocabulary, the term for plants demonstrating physical structure adaptation to arid conditions is “xerophytes.” (Personally, I think the term is catchy.) Xerophytes are the largest group of plants living in the deserts of the American Southwest.

One great example of a xerophyte adaptation is that of the rose family, commonly known as the cactus. The cactus adapted its physical characteristics in several effective ways: Most cacti have modified their leaves into spines, developed a shallow root system to capitalize on scant amounts of water, and created a water storage system in its stems. The spines provide shade and help break up the drying effects of the wind, help collect moisture and add protection from animals attempting to eat its stored source of water. Finally, cacti developed a waxy skin, sealing in moisture, thus reducing evaporation. Amazing. And these are adaptations from just one plant family.

The great thing about a plant’s physical adaptation is that you don’t need a microscope to see or appreciate it. Other plant adaptations to look for are those fine hairs I mentioned earlier. The fine hairs on many desert plants also act as a wind break; they produce small shadows on the plant surface that helps reflect light, much like when we humans wear a white shirt.

Yerba santa

Yerba santa are such plants that do this and are plentiful around the Placerita Canyon Nature Center as you ascend into the chaparral. Scrub oak tree adaptations display a waxy substance on their leaves and stems, helping the plant reduce its water loss. Oh. And look closer at the leaves: They are rolled. This helps reduce the leaf evaporation by reducing the surface area exposed to the sun. Also, the trees’ “umbrella” provides shade to itself. Leaf debris helps trap condensation and helps lessen the evaporation of water from the ground.

Ever wonder why a yucca’s leaves dry up and lay on the ground, still attached to the plant? This is the plant’s ability also to provide shade to its roots. The yucca leaves are also curled, which provides the same evaporation protection as the oak tree leaves.

There are many other adaptations to look for. Small leaves on a plant translate into less surface area from which water can be lost through evaporation. Vertically growing leaves help reduce the direct sunlight exposure to both sides of the leaves. Thick leaves act as a form of insulation which slows evaporation. The list goes on.

Now on to behavior adaptation, which is somewhat similar and yet different. It is defined as “a behavior or action that an organism does or uses to help it survive better.” How do plants change their behavior, you ask?

One behavioral adaptation we all are familiar with is when trees lose their leaves due to the change of the season. Some desert plants have developed the same approach, using the seasons of the most moisture or coolest temperatures to grow. Other plants that appear dead are sometimes just dormant, conserving their energy until water is available.

Yet another plant behavioral adaptation is how the plant orients its leaves to minimize the amount of surface area to the sun, or to grow its leaves to face south, thereby preventing sunburn and water loss. (This is generally more noticeable with the beavertail cactus due to its large pads.)

Finally, a behavior adaptation that astounds me and one that I find difficult to explain without getting into trouble… It is a well-organized and water-efficient process called crassulacean acid metabolism, or CAM. Succulents and semi-succulents are able to determine when to store the energy from photosynthesis while regulating transpiration. During the arid times of the year, this process is delayed until the evening when the temperature is cooler. This reduces the amount of water evaporation from the plant.

To me, this is an ingenious, problem-solving plant. Next time you’re out and about, look at the plants that surround you. Every plant has some type of adaptation that allows it to survive and to thrive in this environment.

Gini Lomerson is a docent at the Placerita Canyon Nature Center.