| This transcript and the images that accompany it are presented unedited from the television show 'Outdoor Nevada'. Although the show no longer airs it was originally presented on KLVX, channel 10 in Las Vegas, Nevada |
| This transcript and the images that accompany it are presented unedited from the television show 'Outdoor Nevada'. Although the show no longer airs it was originally presented on KLVX, channel 10 in Las Vegas, Nevada |
Under normal circumstances I'll hike three, four, and five days a week. My friends ask me if I don't get bored hiking the same terrain over and over again. The simple answer is no I don't. The reason I don't is that I always look for the mystery around me. And in the desert the obvious mystery is how anything survives this brutal environment. Take for instance the creosote bush. It's difficult to spend any time outdoors in Nevada without seeing this plant. It has survived here for thousand of years. And like all plants that live in the desert it has had to make many different adaptations.
One of the most important adaptations that all desert plants have to evolve is a way to insure their water source. In the case of the creosote bush it does so by isolating itself from other plants. There are conflicting reports on how this is done. Some believe that it emits a chemical substance that disables other large plants from growing around it. Others believe that it is the root system that disables the other plants. However it is done, as you can see, it has managed to keep the other plants at bay.
As you hike through the desert see if you can identify other plants that isolate themselves and try to figure out how they do it. Here, for example, is the Red Bud. A rather nondescript plant isn't it? At least the way it appears here. Had you seen it about a month ago it would have been a mass of purple flowers. A startlingly beautiful sight in the middle of the wash.
And that's the way you'll see it. Isolated, in the middle of a wash. It accomplishes this through it's unique seeds. These are fresh seed pods. The seeds haven't fully developed yet. But here in the wash there's a matured seed pod, and a matured seed. Notice how hard the surface is. I can't even dig my thumbnail into it.
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In order for this seed to germinate it needs to be scored. Nothing accomplishes that task better than a wash. Because of the force of flash flooding, and the amount of water that goes through the wash, the seed is insured of two things. One, a large water source, at least occasionally, and two, it will be transported away from the parent plant. Thereby giving it more of an opportunity to grow.
Whether plant or animal the key to survival in the desert is water management. A plants primary water loss is through it's leaves so different plants have evolved different leaves. Here are just a few things to look for. Notice how the leaves of the Mojave yucca are shaped to channel rain and dew to the center of the plant. The leaves of the Manzanita have a leathery surface and are positioned vertically to provide as little surface area to the sun as possible. The leaves of the Creosote and the Desert Almond are small and multi-directional insuring that some of the leaves will remain in the shade throughout the day.
 Mojave Yucca |
 Manzanita |
 Desert Almond |
Other plants have modified leaves that serve different purposes. The spines of the cactus protect it from animals, and provide it with some shade.
On the underside of most leaves are microscopic openings called Stoma. These are the openings through which the plant breaths. Your mission, should you decide to accept it, is to find out how each plant has adapted to protect the stoma during the heat of the day.
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Without a doubt, my favorite story of plant adaptation
involves the Desert Trumpet. That's the common name. The Latin name is
Eriogonum Inflatum. You can figure out where it gets the inflatum from.
In this little bladder is stored carbon dioxide. You see, at night, when
the plant performs cellular respiration, it exchanges oxygen for carbon
dioxide. Then during the daytime when it's necessary to utilize the carbon
dioxide for photosynthesis, it relies on the high concentration of CO2
that it stored up during the evening. That plays into the theory that
we've been talking about where a plant in the desert needs to keep it's
stoma closed as long as possible. Thereby avoiding the evaporation of
the life giving water.
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Adaptation may be the biggest mystery in the desert but it isn't the only one. As you investigate the desert plants try to figure out how the flowers are pollinated and what animals play a part in that, which plants are edible and which aren't, and how the native Americans knew which was which. As you hike, investigate and imagine. There is so much to learn and so much to discover
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