Our Window on Nature

When we think of palm trees, we imagine tropical beaches and pineapples, and dancing girls shaking their hips to the rhythm of drums. Palms belong in Hawaii or Bali, or at least in the Florida Keys.

In California, however, native fan palms are surrounded by desert. Sound like a contradiction in terms? These California fan palm oases aren’t widespread, but rather are tiny pockets of vegetation, a carryover from a time when the entire area was blessed with a tropical climate.

Isolated though they are, you can still visit some of these palm oases on your next trip to the Southwest.

During the Miocene and Pliocene epochs, southern California, northern Baja, and western Arizona enjoyed warm and wet weather. Sunny skies still dominate those regions, but now water is limited to trickles and ponds. Beyond reach of the moisture, desert extends toward the horizon, giving life to a few mesquite trees, and patches of creosote bushes and bur sage. (Read the rest …)

When we were kids in school, it was common knowledge that California’s redwoods were both the world’s oldest and its tallest trees, and that the earliest of them sprouted at about the time Jesus Christ was born. Then some wise guy discovered bristlecone pines of twice that age growing atop the barren peaks of California’s White Mountains, and we had to revise our thinking about longevity.

Now another researcher from the Golden State has thrown us a curve. Dr. Frank C. Vasek of the University of California at Riverside claims to have found a new “oldest living organism on earth” growing in the Mojave desert — only this time, it’s a bush.

Travel through the Chihuahuan, Sonoran, and Mojave deserts from Big Bend National Park to Joshua Tree National Monument, and the most common form of vegetation that you’ll find outside your window is the creosote. This bush thrives at below sea level in Death Valley. It grows where nothing else will, in the desiccated plains surrounding Yuma, where there is a miserly three inches of rainfall a year. Creosote even tolerates being buried by sand dunes, as long as it can grow fast enough to keep a few branches poking up through the sand. In short, this plant is a survivor.

It was at least 11,700 years ago that the American Southwest turned into a desert as we know it. The last Ice Age ended, the climate warmed and dried, and conditions were ready for new forms of vegetation. Creosote was the first plant to inhabit the desert terrain, and since the oldest creosote is estimated to be 11,700 years of age, we must have had deserts around for at least that long.

(That makes the oldest living creosote twice the age of the oldest bristlecone. Sound familiar?) (Read the rest …)

This country is not only peopled by immigrants, but it’s vegetated by them as well. A high percentage of the plants you see when traveling across the North American continent are actually non-natives.

The seeds of these first exotics, as they’re called, arrived right along with the explorers and colonists. Some were intentional imports; others weren’t. Grasses such as timothy, crabgrass, and ryegrass were used to feed cattle. Wild parsley and chickory were used for food, while foxglove, coltsfoot, and tansy served medicinal purposes. Other plants were brought for their beauty, in an effort to ease the loneliness of life in a new land.

A couple of centuries later, botanist J.M. Fogg found that 14 percent of the plants listed in Gray’s Manual of Botany - more than 1,000 species in all - were introduced.

Not all of these non-native species came as invited guests, of course. Many crossed the ocean attached to the clothes of the colonists or to the fur of their animals. In his book North With The Spring, naturalist Edwin Way Teale points out an example of how it can happen. (Read the rest …)

Last month I lost my keys. That didn’t bother me nearly as much as not having my most-used naturalist’s tool readily available. On my key ring I have a small ten-power magnifying glass.

When I’m outside I usually have my binoculars, I often have a camera, but I always have my keys and a way to examine whatever catches my attention. I think that particular magnifier has probably traveled in my pants pocket for at least 25 years.

What can you do with a magnifying glass? Have you ever seen the delicate hooks that hold a bird’s feather in it’s streamlined shape? Or tried to figure out how a tiny tree frog manages to stick to the outside of a sliding glass door?

From the miniature scales on a butterfly’s wing to the texture of the bark from a trailside tree, the world seen through a magnifying glass will reveal details that most will never see. Try it on your next outing and, like me, you’ll never leave home without one. (My keys were found and returned, magnifier included.)

It’s the stuff of science fiction flicks - a species multiplying without restraint until it covers the earth. In one version, insects with no natural enemies soon devour all the plant life on the planet. Or the reverse, a plant extends its tendrils around all other living things, slowly smothering them to death.

Luckily, when plants and animals evolve in a particular habitat together, each species has its own control in the form of other plants or animals that keep its growth within bounds - as long as man doesn’t interfere.

But it seems to be the nature of mankind to always want to improve things just a little. Sometimes we do it by accident, but as often it’s a purposeful intrusion. And sometimes the result is havoc. (Read the rest …)