One slow day, after driving the length of a blank drag, McCarson gave me a concentrated lesson. We parked at the edge of a ranch road. In the adjacent dirt, day-old prints held faintly for a while and then disappeared into mesquite. McCarson checked the angle of the sign and pointed at the horizon, toward the group's destination. Then he pointed at a deer trail. 'I can see all kinda sign through there,' he said, and strolled off to make a cell-phone call.
But there was nothing to see: vacant inflexible earth, sparse mesquite-branch detritus, mesquite leaves in inconsistent profusion, various and occasional flat square-inch plants-beggar's-lice, hore-hound, hedge parsley-and rare tufts of short grasses. All color fell along a drastically shortened mustard-olive-ash continuum. The longer I went without seeing anything, the harder I looked at tiny things close by, and the more obdurately flawless they seemed.
McCarson ambled back. 'You wanna see more but you ain't,' he said. 'That's the maximum the earth's gonna give you.' He aimed his cane at some beggar's-lice. I got close and saw that several stalks had been nudged forward and now leaned at a slight angle, maybe thirty degrees from their natural posture. McCarson pointed to two seedpods the size of ball bearings which had exploded under downward pressure. He pointed to a half-inch mesquite twig that listed a little; its bark at the contact point was a fine-particulate smear. He pointed to a piece of ground the size of a playing card: half the stalks in a tuft of buffalo grass were stabbing ardently forward, and the adjoining earth had also been compressed-once spherical granules and clods of soil urged down toward two dimensions-and this compression was continuous and equivalent in degree through the two mediums of grass and earth.
These pygmy symbols were all within six feet, but they were isolated, camouflaged, and enclosed by a lot of pristine terrain-they didn't relate to one another directionally. McCarson waited for a moment while my eyes struggled to absorb them, and then strolled off. My eyes didn't absorb anything. I was afraid to move and contaminate the sign: I'd been immobilized by tininess. From somewhere in the brush, McCarson said into his cell phone, 'Did those spearguns come in yet?'
After a while, he came back and pointed to a small area in a patch of mesquite leaves, which are very thin. I couldn't see anything; the leaves appeared to be flush with the ground. Then I got to within a few inches and noticed that they hovered microns above it, as if they'd been levitated by some exceptionally weak force- static electricity raising arm hairs or surface tension holding water above a glass rim. McCarson's area-he kept his cane trained on it-was composed of undamaged leaves that were truly flush with or partially embedded in the earth. The compacted region was a few inches long and about the width of a shoe sole.
'See those dingleberry bushes?' McCarson said. They were the size of Ping-Pong balls, and from a distance I couldn't tell that they'd been crushed: in two dimensions, they retained their fundamental color and some unbroken seeds and a remnant network infrastructure, the way road-killed toads can look like living toads minus a dimension. Up close, I saw fine fragmentation and a uniformity of flattening-a broad pad of compression-that only a shoe, not an angular hoof or a puncturing paw, could have made.
Sign cutting is overwhelmingly hushed and uneventful, but the screen of the ground shows action. Trackers find bits of skin and sock on the fishhook spines of horse-crippler cactus and watch the stride transformation and inexorable decline in mobility as the injury worsens. They watch as groups exhaust themselves and start resting more frequently, and as disoriented or fractious groups splinter. The day after a moonless night, the ground shows walkers equivocally chafing their way through mesquite thickets.
Agents watch as weak people stop so that everyone else can go on, and as they later stand up and try to keep going or give up and try to get caught. Very occasionally, in summer, the ground leads Brackettville agents to corpses. Death in the brush is notable for the attempts that dying people make to undress: a dehydrated, overheated body swells as death approaches, so the dying remove their shirts and shoes and socks, and unbuckle their belts. They seem to find comfort in order, folding items of clothing and arranging their belongings. They prefer to die under the boughs of trees, on their backs.
After a few nights sleeping in the brush, people emanate an odor of campfire smoke and sweat that can float for hours over an abandoned campsite. In wetter weather, the smell of canned sardines persists for a day. Cutting trails, agents step over shit and piss and blood and spit. They find handkerchiefs, pocket Bibles, bottles of Pert Plus, and photographs of daughters with notes on the back ('Te extrano. Regresa a casa pronto. Te Amo, Isela'). They find message-board graffiti on water tanks ('23/2/03 Por Aqui Paso Costa Chelo Felipe L. Miguel'), and the roasted remains of emus, doves, jackrab-bits, and javelinas. The great majority of illegal immigrants are adult men, but sometimes agents find diapers and tampons and tiny shoes.
As trackers move through diffuse fields of abandoned objects, fixing the age of the sign, they assure themselves that they're walking through a group's recent past. They want to walk right into its present. They want the sign to turn into its authors. On live trails, the metamorphosis feels imminent, because it always could be. Groups stop unpredictably; if your group lays up at the right time, you'll find yourself disconcertingly deep in a marginal trail yet two minutes from an arroyo filled with snoring. The people you're chasing might appear on the other side of every rise you crest.
Because sign is so shifty and strongly insinuating, it's hard to avoid equating the trail with the people it evokes. Trackers say they're 'running' or 'chasing' a trail; they say they just 'caught' a trail; they say, 'That trail got away.' The language of tracking treats the sign at the leading edge of a trail as the group itself. After cutting a trail's frontier, trackers say things like: 'They're in this pasture,' or 'They're right there trying to find a good spot to jump the fence,' or, simply, 'They're here.'
When you start to see sign, everything unrelated to the trail vacates your mind. Sign cutting is a vigil with no clear object: the sign mediums continuously reconstitute themselves. You often find valuable dominant indicators, but you have to will yourself to remain receptively nonpartisan; otherwise you'll steadily grow blind to divergent marks, and terrain changes will instantly cloak the trail.
Eventually, the microworld entrances: every plant has distinct attitudes and behaviors beyond the obvious-the way it holds its berries; carries and orients and discards its leaves; shrivels and responds to wind; bends with the weight of raindrops. Soil classes reorganize themselves uniquely after a rain. Rocks erode and array themselves in singular patterns. And color and form at that scale are infinitely variable: a cluster of scrub-oak leaves is a thousand shades.
But every medium has, beneath its variability, a composite architecture and a native range of hues, and this is what you have to see, because divergence from it is sign. If you remain rigidly zoomed in, you pick up the endless variations and they hypnotize you and veil the composite. You can't memorize precise schemes of coloration and structure-although the best trackers hold in their heads very good approximations of the hybrid aesthetics of scores of terrain types-but you can learn to see how particular facets of unadulterated landscape acquire a range of colors and shapes over time, so that when you look at a pasture or stream bank or anthill you grasp its physical essence and all its natural deviations, and interloping shapes and colors quickly declare themselves to you. When rain liquefies the ground beneath branch litter, the twigs sink and the liquid soil adheres to the million unique contours of wood and bark and stiffens into a perfect seal. Later, running the trail after the ground has hardened almost beyond compressibility, you'll unconsciously seek out broken seals: millimeter-wide earthworks of shattered crust.
After about an hour and a hundred confirmed sightings, the trail's autonomous sign began to cohere. First it was a stirring paraphrase of recent movement, and then an expression of willfulness pressed into the ground: the overarching intent of a journey. This filled me with an almost violent exultation whose energy was instantly focussed on the next span of information. I couldn't help experiencing sympathetic sensations: I'd see a sneaker-cracked branch and feel it breaking underfoot; I'd see a recently embedded rock and feel my sole bending over it.
McCarson gradually taught me to look for the identifying rhythm of the trail. Group size and behavior correspond to a certain frequency of potential sign; the potential is realized according to the receptivity of the terrain. If two people walk fast and abreast of each other over hard ground while concealing their sign, they'll leave transparent traces; if fifteen people ingenuously plod single-file over impressionable earth, they'll basically plow a new road. Our linear group of five was mainly concerned with speed; they didn't brush out on drags or attempt to walk along the hard edges of animal trails; they didn't bother to avoid print-trapping sandy soil. They didn't stop, and they left nothing behind. Without quite realizing it, I began to think of them as professionals, moving wordlessly in a kind of improvisational accord.
Ultimately, I began to see disturbance before I'd identified any evidence. A piece of ground would appear oddly distressed, but I couldn't point to any explicit transformation. Even up close, I couldn't really tell, so I didn't say anything. But I kept seeing a kind of sorcerous disturbance. It didn't seem entirely related to vision- it was more like a perceptual unquiet. After a while, I pointed to a little region that seemed to exude unease and asked McCarson if it was sign. 'Yup,' he said. 'Really?' I said. 'Really?' 'Yup,' Mc-Carson said.
McCarson experienced this phenomenon at several additional orders of subtlety. In recalcitrant terrain, after a long absence of sign, he'd say, 'There's somethin' gone wrong there.' I'd ask what, and he'd say, 'I don't know-just disturbance.' But he knew it was human disturbance, and his divinations almost always led to clearer sign. Once, we were cutting a cattle trail-grazing cows had ripped up the sign, which had been laid down with extreme faintness- and McCarson pointed to a spot and said, 'I'm likin' the way this looks here. I'm likin' everything about this.' He perceived some human quality in a series of superficial pressings no wider than toadstools, set amid many hoof-compressions of powerfully similar sizes and colors and depths. I could see no aberration at all, from five inches or five feet: it was a cow path. But McCarson liked some physical attribute, and the relative arrangement and general positioning of the impressions. Maybe he could have stood there and parsed the factors-probably, although you never stop on live trails-but he wouldn't have had any words to describe them, because there are no words.
A few days later, some agents were chasing a group of twelve who had crossed the river well after midnight. They had incised their tread marks on many powdered-up roads and drags-the chief identifier was 'a motion wave with lugs around it in a horseshoe in the heel'-and tracking conditions in the brush were good, so at all points the line of travel was easy to establish and forward cuts came quickly.
As McCarson drove fast down ranch roads in quest of cuts, the radio transmitted updates: 'I got 'em here at this deer blind-they got a real good shine on 'em.' 'They're crossing another road right here-hold on, there's some fresh toilet paper.' 'I got 'em laid up here in a real new jacal'-a branch shelter that illegal immigrants sometimes make-'and I got their campfire, still real warm.' Around the fire were slick peach pits and cans with sardine juice in them-a scene so vibrant it was like seeing the group disappear around a corner. 'This is lookin' like one of those rare story-book-endin' trails,' McCarson said. 'Just click-click-click-click.'
Two cuts later, we were at the trail's apex, where six Border Patrol SUVs and about ten agents had converged. The sign described a sudden dispersal into opaque brush: the group had heard its pursuers and taken off. The agents were staring contentedly into meshes of mesquite. A green-and-gold Border Patrol helicopter appeared and dropped to about twelve feet above the thicket, raucously rotor-washing everything; it nosed around the mesquite for about three minutes, and then the pilot's voice came stereo-phonically out of everyone's radio, saying the group was thirty yards away, prone beneath an absurdly undersized camouflage tarp. The junior agents surrounded the hiding place and yelled instructions; twelve depleted men crawled out. The agents told them to sit in a row, perfunctorily searched them, and began discussing transportation arrangements. The captives were all young men; without speaking, they moved from vigilance to dejection to resignation. They received permission to eat, and pulled out Cokes and canned corn and tuna and slices of Wonder Bread and plastic jugs of biologically tinted water.
When I was in southwest Texas, I watched Brackettville agents catch twenty-six people in five groups-all, except this one, by sensor or routine observation or accident. Every capture was quiet: no running, no resistance. In eighteen years, McCarson has drawn his gun two times. He has never fired it. The captured groups were representative: no one had drugs or warrants or enough previous captures to justify detention and criminal charges. The illegal immigrants were all adult men seeking work, tired and disinclined to flee: the chances of escaping after visual contact are slim, and the turnaround time is fast-the Del Rio sector runs a daily shuttle back to Ciudad Acuna. After the capture and pat-down, agents and immigrants, in a momentary common languor, stood around and talked sparingly about the weather or the river level or noteworthy episodes from the immigrants' voyage.
'We just got lost,' an older man with a bronchial cough told me one cold dawn, after he and his four underdressed companions, loitering at a highway intersection, had been searched and ushered into a Border Patrol SUV. 'The stars-the stars were our map at night, but look at the clouds. Look at the sky.' It was impervious, and had been for the past two nights.
Once, I lay on my stomach in a mesquite thicket, waiting with two agents for a group of four that had tripped a sensor. The agents yelled and leaped forward only when the men were within ten feet; the group seized up and went submissively slack in a single motion. After the pat-down, one man began ruefully emptying from his pockets a collection of pretty rocks; for some reason, the agents and I looked away. Walking back to the truck, the men began heedlessly climbing a barbed-wire fence; one of the agents gave them a patient lesson in how to scale it. Another time, a guy whose group had been spotted from the air sociably handed an agent a big rattle and said he'd killed a six-foot snake. The agent examined the rattle deferentially, shook it, said, 'That's a big snake,' returned the rattle, walked the group of men to his truck, and locked them in the back.
Now McCarson and a few other senior agents were leaning against an SUV, watching the junior agents, who were watching the detainees finish their food. I was thinking that as trackers follow illegal immigrants, often right at the mesmerizing limit of what they can detect, they're mustering up the emotions and sensations of mercurial imaginary travelers, and then the imaginary is suddenly, alienatingly replaced by the real: men physically homogenized by days in the brush, all with the same propulsive need. It's a need no Border Patrol tracker will ever be able to identify with. Before the twelve men finished eating, McCarson walked back to his truck and radioed Brackettville to see if anything else was pending.
