Photo by Frank Glaser

Canyon Sin Nombre. "We're going in there," Schad said excitedly, indicating an opening between two rock faces, and then we parked.

The narrow opening of the mud cave was nothing but a slot in the rock, barely wide enough for my shoulders. If you didn't know it was there, you'd never know it was there.

We're going into that?" I said.

Large areas of ground had taken on the appearance of cracked pottery, and we got an even greater sense of how water and wind and time had come to contour this unusual land.

Photo by Frank Glaser

It was deep, and dark, and after five steps, you couldn't see a thing. I used my hands and shuffled at a turtle's pace.

The walls were uneven in the tight passage. You had to shimmy sideways. I leaned over right, then left, with either elbow propping me on smooth rock shelves as I crept, and I put my free hand up in front of my face, to protect myself, just in case.

Edging ahead, I could see no difference between having my eyes closed or opened, so I decided to close them. The cave hooked left, swung back right, and the whole time, the bumpy, irregular walls were no more than a few feet apart.

I kept feeling as though I'd lose my balance in the darkness. But the close walls wouldn't let me fall. The air had turned cool, quiet, still.

View from Badlands Overlook

Photo by Frank Glaser

At least I wasn't alone. My companions — one person in front and one in back — and I kept up almost constant conversation, partially out of fear, and partially because it was useful to rely on echolocation to orient ourselves.

Badlands. "To me, this is one of the many really outstanding places in San Diego County," Schad said.

Photo by Frank Glaser

"This is how bats find their way around," the man in front of me said, "by listening to their voices bouncing off the dark surfaces around them.""Mm-hmm," I answered, more to test this theory than to agree with it.

"It's immediately much cooler," the man in front said. "And of course our eyes are dazzled. But I will tell you that at some point, we will see the light at the end of the tunnel." His tone conveyed palpable excitement.

Slot canyon. At the mouth of the slot canyon, the hills had taken on a gothic appearance - ribs and spires and columns, buttresses, arches.

But the woman behind us was growing exponentially uncomfortable in the claustrophobic dark. "I'm going to turn back now," she said finally, with distinct exasperation.

Only then we heard the call, just a few feet ahead. "I can see light!" It had taken about three minutes to negotiate the dozens of feet of the wavy, constricted cave.

View of mud cave openings

Photo by Frank Glaser

We'd emerged into a chamber, 40 feet high and as wide as a big garden shed, with a cut in the rock near the roof where a light shaft went to the opposite wall. In the faint glow, I was beginning to make out shades, some shapes, my own hands in front of my face. My companions, for the most part, remained invisible.

"The unofficial name for this place is Plunge Pool Cave," the man said. I could start to see the white of his shirt.

This was the bottom of a dry waterfall. It was easy to imagine, instead of a shaft of light up there, a water jet coursing through and down to us.

Mud cave opening

Photo by Frank Glaser

We chatted as our eyes adjusted. "The dark-adaptation process in our eyes isn't completed until something like an hour after the light's gone," the man told us. "We use a different set of cells in our retinas at night, the ones that are only sensitive to black and white, the rod cells. So once the cones, which detect color, stop activating, our eyes are able to sense more in the darkness."

U.S. Parks Department map of Carrizo Badlands

This man was a photographer who specialized in photographs taken in darkness. Which was only one of his many related talents. In fact, the person who'd led me into this cave was undoubtedly one of the premier natural scientists in San Diego, Jerry Schad. The woman, whose tone had turned faintly more confident in the wider, slightly brighter space -- "We should have brought a flashlight" -- was Schad's friend, Chong Yim.

But Schad had taught us not to rely on our eyes. Nature reached us through senses other than our eyes.

To appreciate the essence of the great outdoors, perhaps the only thing better than going alone is to go with a great outdoorsman. And Jerry Schad's credentials as a hiker, biker, photographer, naturalist, and scientist are definitely great. Schad is the first person to write recreation guidebooks for the most ecologically diverse county in the United States, San Diego County. By last count, he's published 12 guidebooks, including the popular Afoot and Afield in San Diego County, and three other volumes about wilderness basics, physical science, and the California deserts. Schad, who is 57 but looks at least ten years younger, also teaches college courses in astronomy, serves as the head of the physical sciences department at Mesa College, and, as I alluded to earlier, has gained some measure of fame as a nature and astronomy photographer.

I was no more than two hours from my living room, but I was standing in a dark cave with a master outdoorsman and his friend, and we were talking about light and sound and...

"The park's trying to deemphasize the existence of these mud caves," Schad told us. "They've collapsed quite a bit over the years, so the word is that they're not really safe."

Um-hmm. The perfect thing to tell people after leading them into a cave. But Schad was the expert, and he didn't sound worried.

After a few minutes, we headed back to the light of day.

Outside, it was 75 degrees, about 4:00 p.m., a November early evening. The three of us had driven over a mile up Arroyo Tapiado, north of Vallecito Creek, in the heart of the Carrizo Badlands of Anza-Borrego Desert State Park, gone into a mud cave, and lived to tell about it.

"To me, this is one of the many really outstanding places in San Diego County," Schad said.

The 4200 square miles of our county boast an extraordinary biodiversity — marine, sandy beach, saltwater marsh, freshwater marsh, lakeside, sage-scrub, chaparral, riparian woodland, oak woodland, mountain meadow, mountain forest, spiny desert, alkali desert -- all within short driving distance.

Almost a quarter of San Diego County — nearly 1000 square miles — is taken up by the desolate terrains of Anza-Borrego Desert State Park.

The name "Anza-Borrego" came from Juan Bautista de Anza — the first European to pioneer a route through the Southern California desert — and the Spanish word for sheep — for the bighorn sheep that live here. The park dates back to the 1930s, when a group of nature lovers petitioned the state government to protect a swath of desert between Mexico in the south, Riverside County in the north, Imperial County in the east, and the Laguna Mountains to the west.

Anza-Borrego is a spot that Jerry Schad had visited eight to ten times per year since the early 1970s -- 300 times in all? -- to do fieldwork, check on trailheads, and add new trips to his guidebooks. He also regularly takes his astronomy classes out to Anza-Borrego to set up telescopes and look at the heavens.

Schad fell for the beauty of the desert when he went camping in Anza-Borrego with friends from grad school. "It happened to be one of those years with just enough rainfall," he said. "And the place was exploding in wildflowers. Entire slopes filled with desert poppies. Color everywhere. I was absolutely amazed. But what clinched it for me on that first trip was this. We came around the corner, and this is on the Borrego Palm Canyon Nature Trail, and right in the crease of the canyon up ahead was all this bright green color. And I realized they were palm trees. I just couldn't believe that vivid color and lushness in the middle of the desert. I got hooked at that moment."

The energy of our company had converted completely after the experience in the tight, dark mud cave. There was an air among us now like the buzz of excited carnivalgoers after the rollercoaster. Our voices sounded different. Steps felt lighter. We were ready for anything. Perhaps Chong and I had gotten hooked on the desert now too.

But the trip didn't necessarily begin that way.

I mean, it was the desert. What was there to see and do that would be worth the heat of the desert?

The first time Schad saw the California desert, driving through the western Mojave, he wasn't impressed. "It was just sort of this ugly, flat, colorless, hot expanse of nothing."

The American poet Wallace Stevens, in one of his most famous poems, wrote about attuning our minds to nature. When nature and man become single-minded, Stevens stated, we might behold "nothing that is not there and the nothing that is."

At the eastern Anza-Borrego park boundary on S2 (the Imperial Highway), which is also the county line, and which is also an immigration checkpoint, a small stone obelisk rises by the side of the road.

The original bronze plaque in the obelisk was stolen long ago. In 1998, local sculptor Nina Karavasiles made a new plaque out of graphite. "This is the desert. There is nothing out here. Nothing."

As we passed the park boundary, discussing the nothing, and the other nothings, Schad told me that I was going to be seeing the desert in its most dried-out state. "Which is kind of good," he said, "because one of the things that's nice about the badlands is that it's so incredibly stark, so maybe you don't want to go there when there are wildflowers."

The starker the better, I thought. If the desert's true color was to have no colors, then I was happy to see it like that. The nothing at its most nothing-like.

Three miles past the obelisk, the badlands gradually came into view.

They were hills, but as you approached them, you looked down on them from the flatter country above. From the rim of the "breaks," as a descent into the badlands is called, you saw a land that was bumpy and gray -- a convoluted, lumpy quilt -- the hallmark of severe erosion.

Another mile or so down the lonely paved stretch of the Imperial Highway, the badlands tumbled to the horizon on both sides. Smoke trees, ocotillos, and cactus dotted the rockiness here and there, but mostly it was hills and grayness for miles and miles in every direction, until the Coyote Mountains rose about 2000 feet out of a blue-silver haze in the eastern distance and the Jacumba Mountain peaks punctuated the west.

Incidentally, "badlands" was never an official geographical designation for a landscape. Instead, the word commonly referred to uninhabitable terrain that was difficult to pass through and bore no practical value to humans. The term originates from dual origins: the Lakota called the topography of the Dakota Badlands "mako sica," literally "bad lands," and French trappers named it "les mauvaises terres à traverser," which means "the bad lands to cross."

Said Schad, "The badlands are a maze. The washes wind around and wind around, and it's like a maze or puzzle. But generally you can't get lost too much because all you have to do is follow the drainage."

Two areas of badlands lie in the eastern portions of Anza-Borrego Desert State Park. The Carrizo Badlands, where we were, stretch south of Route 78, and the Borrego Badlands extend north of the highway.

We'd turned off S2 at the Carrizo Badlands Overlook to park and have a look.

"I just love this really stark stuff," Schad said; "what some people might regard as 'ugly' I think is just beautiful."

Indeed, one man's ugly nothing for another person could be really something.

Several ocotillos clutched skyward like bare spindly fingers. Schad told me that ocotillos send out leaves and flowers up to seven times a year, depending on rainfall. (Our whole time in Anza-Borrego, I saw well over a hundred ocotillos, but only five ocotillos with flowers. More precisely, I saw five ocotillos that each had a single flower hanging forlornly from the tip of a fingerlike branch. Each flower looked almost like a dangling red sock. Two of the five had vigorous hummingbirds fluttering at them.) "The ocotillos are so defiant of their environment," Schad said. " 'I'm going to survive!' That's what they're saying.

"One of the things you get a sense of as you enter this area is you don't see the works of humankind," said Schad. "All you see is nature. You could have been out hiking centuries ago, and when we go out hiking today, we'll see exactly the same thing. So when you're talking about towers as tall as high-rises going right through one of the most spacious parks in the nation..." And his voice trailed off in seeming disbelief.

Schad was talking about the Sunrise Powerlink, San Diego Gas & Electric's proposed 150-mile power line "to connect energy sources in the Imperial Valley to San Diego County." The utility says the line would ensure that the region will have enough power in the coming decade. But its 155-foot towers would also scar the desert wilderness.

Back in the car, we made our way a few hundred feet past the Carrizo Badlands Overlook. It was a right turn down into Canyon Sin Nombre ("Canyon Without a Name"), nothing but a sandy, rocky dirt path hemmed alternately by gentle 30-foot-high hills and 30-foot cliffs.

Schad drove a Honda CR-V with four-wheel drive on demand, and this spot was where the four-wheeling began.

If you're driving through Anza-Borrego, you're either on one of the main roads or you're bouncing and sliding along a wash. In desert parlance, a wash is a dry creek bed. Washes are full of rocks of all sizes, ridges of hard mud, and resolute stands of desert foliage. It's easy to picture water running through a wash. Everything about a wash indicates rushing water: sinuous forms, loose deposits of rocky material, lines of strata in the cliff walls. But most of the time there's no water in Anza-Borrego washes. They're more like the negatives of rivers -- to employ a photography metaphor -- which will be used in future rainstorms to develop ephemeral streams.

"This is a road that passenger cars aren't advised on," Schad said, as we bumped down into the canyon. "The wheels might slip, and we might have a hard time getting back up out of here. And there are some pretty rough sections up here for a passenger car. It may even be challenging for this one."

And if we did get stuck?

Schad laughed. "I've got Auto Club."

A single raven flapped past us in silence, pastel sky behind it. The Honda bounced and crawled through Canyon Sin Nombre.

A kangaroo rat skittered among the rocks. When I pointed it out, Schad told me we'd probably see plenty of those, as well as lizards, jackrabbits, and maybe kit foxes and coyotes. We passed a half-green mesquite shrub and clutches of small plants covered in yellow flowers, desert marigolds. The biggest plant we saw, aside from the palm trees I'll mention later -- a desert willow -- was no more than 20 feet high and wide, with a trunk as big around as my ankle.

But the most common plants, which is to say there were more than a few of them thriving here and there among the rocks and sand, were the smoke trees. Seen in backlight, smoke trees did appear like puffs of smoke. But up close, these bushy wisps were thorny and sharp.

The most extravagant display, though, wasn't provided by plants but by rocks. Desert varnish forms on many desert rocks, adding to the colors of the landscape. A chemical change involving oxygen, iron, and manganese, which occurs over the course of hundreds or thousands of years, causes many desert rocks to acquire reddish and brownish hues. In essence, the rocks are rusting in the relentless sun.

"This canyon is probably the single most amazing geologic showplace maybe in the whole county," Schad said. "There's so much here for people who study rocks. Right now we're in what used to be a streambed, and you can tell that because of the basal conglomerate layer in the rock." Schad pointed to a line of strata in the rock as we drove slowly past. "And above that, there's the less-pocked layers of finer silt where the water once brought it along."

Geologically, what's going on in Anza-Borrego is complicated. But the simplified story is, the San Jacinto Fault wandered into the area and mixed everything up. As a result, you can see every kind of rock there -- sedimentary, metamorphic, and igneous -- all interspersed, ground together, and folded by the motions of a massive seismic fault.

The squiggly lines of strata laced the sides of many hills. But then, in certain areas, the hills looked more like piles of mud. And other places, the mud was cracked like dried pottery. And the types of hills -- mudlike, rocky, stratified, even bonelike -- clustered together by category. In the badlands, you wouldn't often see a mud hill next to a rocky one, or lined hills next to smooth ones, for instance.

"This terrain seems so static," Schad said. "You know, it seems absolutely frozen. But then it obviously changes, and it changes in fits and starts, great catastrophes, like floods and earthquakes, that happen in short time periods, and then it just sits there and vegetation slowly grows."

The rocks reiterated Schad's tale, jutting and waving and speaking of momentary violence followed by long periods of peace.

If Anza-Borrego were an artist, then rain was her paintbrush.

I wondered just how often water might flow in these sandy washes, and Schad told me that it was likely for at least a little water to flow in most washes every single year. "It doesn't take much rain to start a small flood out here," he said. "I came out here one time, years ago, just because I wanted to see water flowing in the desert, and I walked about ten miles on the rims of the canyons, and I could see brownish, turbid water churning through these canyons. And small sections of the sides of the canyons were sloughing off and falling into the water. Because everything is kind of muddy and silty out here."

But the water in Anza-Borrego never stays around for long. In wine-making and distilling, they call the amount of liquid lost during the aging process "the angel's share." In the desert, the angels take the water back quickly. What rain there is in Anza-Borrego falls from December through March. Those are the winter rains, the fairly meager smatterings that manage to get over the mountains, which extract most of the moisture from Pacific storms. Anza-Borrego lies within what's called the "rain shadow" of the mountains.

The rainfall in the desert reaches 12 inches some years, but most of the time it hovers around 6H, according to Michael Rodriques at the park's visitors' center. The amount and timing of these winter rains determines when and how many desert wildflowers sprout. Soaking rains and nice sunshine can lead to a profusion of colorful flowers by April -- desert lilies, agave, palo verde, brittlebush, indigo bush, creosote bush, senna, and cactus flowers.

By June, though, the place is scorching. Hundred-degree days. Hardly any plants are blooming. Smoke trees, for instance, may keep their mottled gray-purply clusters until June.

In July and August, sometimes there is hot and humid weather, because the moisture coming from the Gulf of California, or even the Gulf of Mexico, sweeps across the desert and piles up against the mountains creating thunderclouds and sometimes thunderstorms. But the storms are usually spotty. They dispense heavy rains but often only in tiny areas. The precipitation from summer storms usually adds less than an inch to the total annual rainfall.

By late September, the summer storming is over. "I think October is a great month out here," Schad said as we drove. "It's one of the least popular months. It's quite hot and dry, but the nights cool off, and as long as you stay out of the sun during the middle of the day, the rest of the time is nice."

November is a more benign version of October, and in December and January, Anza-Borrego gets those intermittent winter rainstorms, but a lot of days late and early in the year are crisp and clear, 70 degrees in the daytime, 40 at night.

It was 2:44 in the afternoon. As the sunlight descended behind the Jacumba Mountains, the desert suddenly seemed like a stage, with a spotlight shining on it. This was a much more flattering light than the brutal post-noonday sun had provided.

Crawling northeastward, up Canyon Sin Nombre, we'd covered about two miles in 12 minutes. But at last we'd reached the spot that Schad was looking for, one of his favorite slot canyons.

Something I was beginning to realize -- and which would become clearer as we saw more -- these nameless places, in a slowly shifting landscape, with similar-looking landmarks, might be all but impossible to find without a guide like Schad to show them to you.

"I first wrote about this particular canyon in the first edition of my Backcountry Roads and Trails book," Schad said.

At the mouth of the slot canyon, the hills had taken on a gothic appearance. The mud had dripped and dribbled and re-formed to the point that there were medieval touches everywhere -- ribs and spires and columns, buttresses, arches, and hardened mud outcroppings that looked like gargoyles on a vampire's castle. We found some bat guano at the base of a small cliff, adding to the gothic theme.

"We're going in there," Schad said excitedly, indicating an opening between two rock faces, and then we parked. The cliffs here were 40, maybe 50 feet high. We were in the middle of the sandy path that was Canyon Sin Nombre, parked next to a five-foot-high smoke tree.

"This isn't a true cave," Schad said, "just a slot in the rocks."

We grabbed some water and set out across the soft sand.

"There's kind of a hardness to this desert landscape," Schad said. "But there's a softness too. For example, how soft the sand is as you're walking along it. The rocks are angular in some places, but they're not all that jagged. And this warm weather, to me, this is very inviting. It's a very comfortable place. Even though, for some people, I know it's menacing and sinister. And the best thing, really, is how close this is to San Diego. We didn't even have to rush out here, and here we are. We even took our time."

Everything about that moment in that place seemed to agree with Schad's words. We'd left after noon and lingered over what to bring. And just a couple of hours later, it felt as though we'd arrived on another planet, where the breezes were sultry, the landscape was beautiful, and nothing commonplace could follow.

"I have a picture of the moon from over that ocotillo right there," Schad said at one point. And later he'd take us to find a particular overhead slot -- what he called an "aperture" -- an angular opening in the rocks above us that framed a geometrically interesting swatch of sky.

We passed between two rock cliffs, and the space got tighter and tighter. No roof capped off the slot, so although it was often as constricting as the mud cave would eventually be, at least we could see where we were going. I asked Schad if this winding thin canyon had a name. "Nope," he said. "No name. A no-name canyon off the Canyon with No Name."

We laughed. Schad pointed out a bluish and many-lined rock among the monotone grayness. It looked as out of place as a street sign or a palm tree in the desert. "This is from a different mountain range," Schad said. "Carried down here probably thousands of years ago and left here."

Most of the stone we saw was either smooth and flowing, like the water that shaped it, or dotted and cracked, like the sun that also did its part. For this reason, you could easily tell where rocks had broken and fallen. The piles of new-fall stood out. Seeing what the fallen stuff looked like, you didn't want to stop walking as you passed under the brittle arches and overhangs.

We turned around and snaked our way back out of the tight canyon.

Back in the car, the three of us headed out of Canyon Sin Nombre, slowly over the sand and loose stone, about another half-mile to a crossing of paths, a spot where a canyon, a creek, and an arroyo formed what looked more or less like a big sandy field with some rocks and low trees in it.

"This crossing is called a 'braided wash,' " Schad said.

Official signs had been hammered into the ground at this spot, though they were easy to miss. Canyon Sin Nombre. Carrizo Creek. Vallecito Creek. We headed more or less straight up Vallecito Creek, though this "creek" might more properly be titled a "wash" or a dry arroyo. Soon we passed wheel tracks that veered to the right into the appropriately titled Arroyo Seco del Diablo, "Dry Wash of the Devil."

A mile or so farther up Vallecito Creek, we saw another sign, Arroyo Tapiado. Schad told me the name meant "mud wall wash."

Here, Schad related a story about the Butterfield Overland Stage that used to run from St. Louis to San Francisco, carrying people and mail through the desert in the late 1850s and early 1860s. Anza-Borrego had proven to be a good route through the surrounding mountains, despite the hostile Indians and lack of water.

"There's an old stage station right up Carrizo Creek over there," he said. "Just an old ruin, but it's got a lot of history."

Instead of veering to see it, we turned off Vallecito Creek up Arroyo Tapiado and headed for the mud caves.

Here we saw another car and two women setting up camp. "This place is really a camper's paradise," Schad said. "If you're into solitude and you just want to camp wherever you want, you could go into any place like this, as long as you're not driving over the vegetation, and you can stop anywhere and sleep out under the stars without a tent."

Which was exactly what we would be doing in a few hours. After driving about a mile past the only other human beings we would see that afternoon, we parked in front of the deep slot of Plunge Pool Cave, went inside, and then emerged from our dark adventure.

It was 75 degrees, 4:00 p.m., and now we were buzzing with that post-rollercoaster-like energy.

"That was fun, huh?"

"Yes. That was amazing."

We walked another hundred yards or so up the arroyo and headed fearlessly in through the opening of the Big Mud Cave. A tractor trailer could have fit through with us. Most of the roof had collapsed, which made this place more like a mud canyon than a mud cave. It wound over and down and around for many hundreds of yards and afforded us excellent views of the sky up past interesting mud formations. Large areas of ground had taken on the appearance of cracked pottery, and we got an even greater sense of how water and wind and time had come to contour this unusual land. Parts of it looked like pudding. The half-mile cave trail was a tale of ruin, tearing, crumbling, and wrenching: entropy at work.

After a long trek, over a mile, in and back out through the collapsed cave, we headed to the car and backtracked a mile to the mouth of the canyon section of Arroyo Tapiado, where there was plenty of space to park on firm sand. "Let's make camp," Schad said. It was 5:10 p.m. The temperature had already dipped into the high 60s. It had been 80 around noon.

We laid out our sleeping bags, set up the stove, and got ready to make dinner. The sun had disappeared behind the mountains to the west, and a soft purplish light had set the desert into a beautiful relief. A slice of pink contrail jetted in the distance. Lines of mountains strung the low sky all around. There was utter silence, just us and the bats and their little flaps and peeps. We saw some insects. Darkling beetles walking slowly. A bee or two. And then, at dusk, some sort of nonbiting gnat. Overnight, some flying thing would bite Chong on the bridge of her nose.

Most of the bugs we saw were dead, beetles and bees whose little bodies now were like colorful pebbles in the sand.

After a meal of salad, soup, and fettuccine Alfredo with tuna, the stars came on all around us and the temperature dropped. Schad the astronomer announced that it was time for our lesson in the heavens.

By 6:20, the sky was a mass of stars. So many of them. They looked like spilled glitterdust or snowflakes getting ready to fall. And right down the center of the sky, looking like nothing so much as a spinal cord, the Milky Way Galaxy stood forth bright and clear.

"In recent years, they've come out with green lasers," Schad said. "Have you seen one? They're really good as pointers."

And then Schad turned on his green laser. The beam looked light-years long. It seemed as though Schad could touch the stars with it. "Okay," he began, "let's start with something terrestrial. Light pollution. For example, I can see you. And if we didn't have light pollution we'd see a lot more stars."

I couldn't imagine seeing more stars.

"Over there, we have the lights of San Diego," Schad said. He didn't need his laser to point out the domelike glow to the southwest that backlit the peaks of the ten-miles-distant In-Ko-Pah Mountains. "And looking a little more that way," he said, turning south, "Tijuana and Tecate are contributing more and more."

Turning back north, past San Diego's ominous glow, he said, "And then you can see, where it gets a little darker, that's Camp Pendleton. And then there's Los Angeles. We're a long ways away from L.A., about a hundred miles, but you can still see its light. And then there's Coachella Valley and Palm Springs. And over here, under the eastern sky, there's a pretty big dome of light. That's Imperial Valley and Mexicali, about 40 miles distant."

Schad had turned us fully around, 360 degrees, and almost every stretch of the horizon was eerily backlit by the lamps and bulbs of cities.

"I consider this light pollution to be like a noose," Schad said. "And it's tightening and tightening and tightening. If I could have brought you out here in 1972, when I first saw this place, San Diego was like that," and Schad pointed at the considerably dimmer Mexicali glow, "and L.A. was a similar thing. So it's gotten a lot worse. And it affects the sky up to about 45 degrees. And it's not quite as dark as it used to be at the zenith."

Then Schad delivered a crash course in astronomy. His green laser touched and traced the summer triangle and the Northern Cross and all the visible zodiacal constellations. He told stories relating to many of them. "This is like my Astronomy 109 class," Schad said, at one point. Schad was a good teacher, and his excitement when it came to the heavens was infectious.

Schad pointed out the Andromeda Galaxy -- "That's the farthest you've ever looked at with your eyes," Schad said -- and he talked about photographing the heavens, and he described how star time relates to earth time and moon time and sun time. As he talked, the stars seemed less like some imaginary video game with battles and alien races and more like the beautiful, stately, well-measured backdrop for every human action. We talked stars for over an hour, and we probably could have talked more.

"The thing about the sky," Schad said, as he finished his star lesson, "unlike this badland landscape that shows its changes in fits and starts, the sky is mostly incredibly regular. It's just running like a clock."

By now, it was 7:30 p.m., and getting chillier, and Schad had an idea about going for a night hike. When I mentioned to him that I'd never heard of night hiking, Schad said there was really no such thing. It was something he just liked to do.

"It's more of a black-and-white experience," he said. "Landscapes are really quite beautiful when the moon shines on them." And then it made sense to me how an astronomer might cultivate an appreciation for hiking at night. "I've seen Venus so bright at night that it cast a discernible shadow," he said.

There was hardly any breeze, but you could feel the night air moving. We kept passing through warmer and cooler pockets of it. One moment, I'd feel chilly, and the next I was quite warm. "The cold night air is displacing the warm stuff," Schad said. "And it's moving down through these canyons just like flowing water would."

Hiking down the washes by starlight, winding and curving, it was easy to imagine being water.

Schad led us back up Arroyo Tapiado in the dark, and after about a mile, using flashlights intermittently, we found the entrance to another slot canyon.

This canyon had many cavelike features and covered areas, though most of it had collapsed. The path coiled and twisted up through 30-foot rock and mud walls, and a narrow river of stars followed us in the dark sky. We used flashlights most of the time, although we'd turn them off at times too, to appreciate the natural light. The darkness provided an intimacy with the landscape. You had to touch the walls more and feel the ground. I began to form an impression of the sun as a kind of boisterous, loud child, flooding everything with heat and light and making it difficult to see the details of things. At night, the subtlety of the badlands stood out.

We followed the canyon/cave for almost a mile and then turned around and followed it back down. Despite the fluctuations in temperature, it was getting colder. But walking had made us warm.

By 9:15, after about a two-mile walk, we were back at camp and more than ready for bed. There was a faint smell of wood smoke, probably from the campers we'd seen up near the mud caves. I crawled into my sleeping bag next to a tiny yellow-flowered bush as moonlight crept across the valley. The only sound was the periodic plaintive roar of distant planes.

I fell asleep almost immediately, although I woke up several times during the night. Twice I heard coyotes' yips and barks a long way off.

I awoke at 5:45 a.m. The temperature had fallen to just above 50 degrees. High pink cirrus clouds streaked against the gradually bluing sky. The waning gibbous moon was a chalk smudge. There was no sun yet, although orange sunlight was visible on the western peaks of the In-Ko-Pah Mountains in the morning silence.

We sipped white tea, munched red grapes, and gradually broke camp.

By 6:30 we were on our way as a single raven cawed overhead.

"This is the kind of lighting I love," Schad said, referring to the soft pre-sun glow. "All the colors are muted now. Pastel shades. Olive green. Beige. Rust. Everything just stands out. Like a painting."

On the way up out of Vallecito Creek, we saw a street sign standing on a rocky hill. That's right. A street sign. Hollywood and Vine. "Somebody put that there years ago," Schad said, chuckling. "The most glamorous street corner in L.A. Looks pretty out of place here, doesn't it?"

Out of place, yes. But it wasn't the most out-of-place thing I was going to see that day.

We drove another three miles, up out of the Carrizo Badlands, and got back on S2, the Imperial Highway, near the trailers and homesteads of Canebrake Township. Jackrabbits bounded among the agave plants, scurrying away from the car at high speeds.

We headed northwest through Earthquake Valley, through the Yaqui Pass, about 40 miles, and then another 15 to 20 miles northeast through Borrego Springs. Then we turned due east on S22, the Borrego-Salton Seaway, and went the last 7 miles into the Borrego Badlands.

At 8:15, we reached the Arroyo Salado turnoff and headed south down the sandy wash toward our next hike. Behind us, the highest peaks in the area, the Santa Rosa Mountains, jutted down out of Riverside County. We weren't more than ten miles west of the Salton Sea.

Again, it was slow going. It took us about half an hour to drive three miles.

Schad's plan was to show us the only 23 palm trees standing in the Borrego Badlands. The 23 trees were growing in three small oases, in groups of 17 and 5, and then a single tree standing alone. We would drive to the largest stand of palms, park the car, and then walk a wide loop to see the others.

Seventeen Palms Oasis was a string of high trees, all about 30 to 40 feet tall. Crabgrass and smoke trees grew among the palms. The sound of fronds clacking in a breeze added to the buzz of a stray insect and the passing of a high plane. It wasn't yet 9:00 a.m., but already the temperature had climbed near 80 degrees. The sun was relentless.

Around us, scaly, crumbly mud hills were covered with small, loose rocks. It looked a lot like the moon, with little vegetation, except for this unexpected stand of high, green trees. "There's water near the surface here," Schad said.

And then he related how this oasis was once a meeting place for miners and other desert travelers. "They'd leave each other water and messages here," he said. And to commemorate that, there was still a barrel wedged between two of the palms, with a bunch of notepads in it.

At Schad's behest, we "tanked up," drinking multiple bottles of water. And then he led us across the rocky waste, through the nothing that was there, using his topographical map. There was no path. He stopped once to point out the color of the setting moon. "The moon's about this color," he said, and he kicked at a blue-grayish rock with his foot. "If you took a picture of the moon, it would have about the same exposure value as this rock."

Multiple animal tracks laced the sandier areas among the hard mud and loose rocks. Every so often, a jackrabbit would start up and dash off at high speed. We also saw networks of kangaroo rat tunnels but no kangaroo rats. Dragonflies throttled back and forth over a small stand of evenly placed creosote bushes.

I kept getting pestered by a horsefly who must have thought I was a horse. By then, I might have smelled like one.

We walked over uneven ground for a half mile or so, and then, entirely without warning, the ground dropped away. It was a sharp sliding drop, a "break" into the badlands, down about a hundred feet. In front of us, we could see for miles -- miles and miles of roiling eroded land. Juts and lines and swipes of brownish land. All the way to a slight mist in the distance and the buttes and peaks of the Pinyon and Fish Creek mountains.

We found Five Palms and drank more water. The trees were arranged in the side of a barren hill in such a way that they looked like two adult palms watching over their clustered children.

But our final stop was going to be Una Palma, One Palm, a single tree, alone in the desert badlands.

As we walked and wound around and up and down, I could tell that a trail was part of the nothing that was not there. Although we weren't lost, per se, just meandering. Schad kept getting our bearings, using his map and the blistering sun. But it wasn't easy going. Not at all.

Somewhere between the palms, in the nothing, Chong found what Schad had called a "concretion." He'd explained to us how, over the years, sand would gather and collect and form some pretty strangely shaped rocks. "I've found concretions in the shapes of many letters of the alphabet," Schad had told us. "S, T, U, Y, and even an O, once." But I didn't really understand what Schad was talking about until Chong found her hilarious concretion. It was a gray stone almost a foot long, and it looked exactly like a pickle with a nipple. I found out later that there's a website dedicated to these concretions, http://home.att.net/~amcimages/dunn.html.

The land looked like elephant skin. Gypsum sparkled from some of the hillsides. It was bury-a-body desolate. Eventually, we saw two motorcyclists zoom past, but otherwise it was just us and the land and the sun. My mind was becoming desert-tuned.

Wallace Stevens wrote another poem, his final published poem, in fact, about a single palm tree. "Of Mere Being" dealt with "the palm at the end of the mind." In Stevens's poem, the desert was a "bronze decor." And there was a bird in the branches of the tree, singing a song, and its "fire-fangled feathers dangle down."

As I thought about this, all of a sudden, there it was, off in the distance, peeking above the textured hills. The green corolla of a single palm tree.

It was over 80 degrees, 10:05 a.m.

I wondered if I'd see a phainopepla bird up there singing its wurp and wheeda-lay. Instead, the tree stood alone, but its own fire-fangled fronds did dangle down.

We made our way over to the base of Una Palma. It was bizarre to see a 50-foot tree thriving in such treelessness. How did it get rooted? It rose up out of a packed mud slope. And why hadn't any of its own seeds found purchase anywhere?

I believe I can safely say that until you've seen one palm, you haven't seen them all.

The land had a meditatively interesting sameness -- sinuous repetitions, easy on the eyes and suggestive to the mind. The sun pounded down, but the breeze had turned to wind. Felt good.

All around us, six million years' worth of fossils were emerging from the eroding ground and becoming slowly visible. Animals were furrowing for their food. And here was this one tree standing alone, as out of place as I was.

"What a lonely guy," Schad observed. "All by himself out here in the sun and dirt."

I'd been noticing that Jerry Schad used very little hyperbole in his speech. "No need," he said. "Nature speaks for itself."