What Is Cryptobiotic Crust?

There were signs everywhere at Arches warning people to stay on marked trails, because if you left them you risked stepping on and destroying the soil’s cryptobiotic crust.

Wait, cryptowhat? Isn’t that something to do with bigfoot? No, that’s cryptozoology. Cryptobiotic crust is a black layer that forms on the surface of the soil in arid regions, and as the name suggests, it’s actually alive.

See the black stuff on the ground in this photo? If you do a Google image search, you can find other, better images, but basically it’s made up of a mixture of stuff like bacteria, algae, fungus, lichens, and mosses. It’s delicate enough to be severely damaged by a single footprint or tire track, and depending on conditions it can take as long as a century to re-grow when it’s damaged. Soil crust decreases erosion, alters how water infiltrates the ground, and benefits plants by increasing nutrients in the soil. It can be an important part of desert ecosystems.

Did all the warning signs really stop people from leaving the trails constantly? Well…

Nope.

Long-Nosed Leopard Lizard

One of the interesting creatures we saw at Arches National Park was this large lizard, who crawled out from under a rock as we passed, apparently wanting to enjoy the morning sun.

It’s a long-nosed leopard lizard (try saying that five times fast), or Gambelia wislizenii. While we watched, it repeatedly crawled back under its rock only to reemerge a moment later, apparently unable to decide whether we were really a threat. When we finally continued along the trail, we were surprised to immediately find two more!

Apparently the red markings along the sides of these first two mean that they are gravid females. These diurnal lizards eat other, smaller lizards as well as insects and small rodents. Though there’s nothing in the photo to give a sense of scale, the ones we saw were easily a foot long.

Above, a male (no red bars) basks on a rock. These guys have a close cousin, the blunt-nosed leopard lizard, that is a federally endangered species.

More to come…

More Arches

Turret Arch
Double Arch
Skyline Arch
Landscape Arch

The features that give Arches National Park its name form when enormous fins of sandstone are weakened by alternating freezing and thawing of water that seeps into the porous rock. Once a hole forms, it is enlarged by weathering and rockfalls, and eventually it will collapse completely. There are over 2000 natural arches within the park’s borders.

Delicate Arch

The most iconic image of Arches National Park, the one that’s on Utah’s license plate, is Delicate Arch. Visiting Arches without seeing Delicate Arch would be like visiting Yellowstone and not seeing Old Faithful. But, unlike many of the park’s famous features, it’s a bit of a hike to get to. In fact, from the trailhead you can’t actually see the arch at all.

You begin by crossing Salt Creek, described at length in Edward Abbey’s Desert Solitaire, the park’s only permanent flowing water – pretty but too alkaline for human consumption.

After that the path climbs into the cliffs for a mile and a half. For at least a third of that distance, though, the “path” is more idea than reality, as you’re traversing bare slickrock. No soil or vegetation for a path to be worn through.

The only suggestion a specific trail to follow comes in the form of a series of small rock cairns left by previous hikers.

Finally you round the final bend… the path at this point is a ledge hewn directly into the side of a cliff…

…and there it is before you, at last. (Note the people at the lower left of the arch. It’s bigger than you first realize looking at a photo like this.)

If Delicate Arch has any significance it lies, I will venture, in the power of the odd and unexpected to startle the senses and surprise the mind out of their ruts of habit, to compel us into a reawakened awareness of the wonderful – that which is full of wonder.

Desert Solitaire, by Edward Abbey