Last April, Jason and I surveyed lichens in the northern Mojave. It’s the second field season of a three year study involving lichen biodiversity along the ecotone of the Great Basin and Mojave Deserts in Southern Nevada.
And what did we find? Lichens, yucca people, bizarre geology, and a new rock climbing area that’s being developed at Davidson Peak (Eastern Mormon Mt Range)..
There’s alot to be said, but photographs speak so much louder than words, at least until we get to posting Part 2 which summarizes our preliminary lichenological results, with a special emphasis on the soil crust communities we found. Stay tuned 🙂
The geology in this part of Nevada includes alot of ancient riverbeds that have been cut out by seasonal washes, leaving interesting sandstone formations telling the story of these old creeks, rivers, and perhaps even deltas.
Large rocks with iron rich clay on the bottom, and middle, interspersed with fine rocks; then seemingly rather suddenly, a rush of paler finer sediments were laid down continuously for a very long time.
A little rounded pebble lain down with the fine pale sediments, these pebbles looked to be of various types, from granitic to volcanic, and most rounded from their journeys descending from different ranges uphill of the ancient river they eventually rested within..
Jason checking out lichens in protected areas of sandstone.
Rhizoplaca marginalis – if you’re from California you might be doing a double take. Yup, we found it in the northern Mojave in southeastern Nevada — the first documented report outside of California! Jason nearly jumped to the moon when he found this one. Needless to say its extremely rare out here, we weren’t able to locate it at any other site in our northern Mojave, Lincoln Co. Nevada study area.
Caloplaca squamosa group. Also known as SunBurst Lichen, this particular group of species has a squamulose thallus that’s kinda like a scaled body, rather than simply having discs like many other species in the genus or having an extremely well developed lobed thallus where the lobes look like long fingers extending outwards (e.g. C. trachyphylla). The C. squamosa group is one of my favorite lichen groups this year because there’s a bunch of look alikes, but if you’re careful, you just might find one of the rare species!
There’s alot of limestone in this area of the Mojave, and calcareous substrates usually host a unique community of lichens. But not at this site where an odd iron rich intrusion intruded into all the interesting microhabitats throwing off the pH and the texture. And it didn’t even host interesting lichens itself, just the common ones. And it was wicked hard to collect off of too. Stratifying this site into calcareous or siliceous categories for analyzing community composition is not a possibility. A dud of a site all around. Except for the more interesting question of — what in the world was laid down in this inland sea to create this super hard ferrous like material? Iron rich dinosaur tissue?
Here’s a closeup of that intrusion talked about above. Our geologist friend Cathy Hicks explained that its chert — formed from fossilized sea creatures. Cherty Limestone is what the geological strata is called. The patterns the chert forms in the limestone is incredible — looks alot like a matrix of iron rich coral.
The fossil of an ancient bivalve perhaps, found in the cherty limestone.
A liverwort in the Mojave? Indeed, along an intermittent stream near a 1940’s homestead.
Poured cement floors of this homestead dates it to the early 1940’s. World War II was about to break out, the westward rush after the dust bowl had already subsided. These folks were most likely looking to get rich – old narrow mining paths still cut through the hills.
Even the Mojave got some of the intense precipitation of the winter of 2016-2017 that racked California with major flooding. Here in the eastern Mormon Mountains, Encelia vifinensis was going gangbusters, a true megabloom, exploding across the entire landscape.
Encelia virginensis’ delight. The far range in the distance is the Virgin Range, and within it flows the magical canyonous Virgin River.
Long Nosed Leopard Lizard – what a cutie.
A ravenous rock. Check out those quarzite teeth!
Desert Horned Lizard. Amazing armor. My hero.
I’m not sure what spider this is, and noone on BugGuide.net has gotten back to me yet. If I was to give it a common name, it’d be the horseshoe crab spider.
No post on the Mojave would be complete without sharing photos of the Yuccas. Here’s the magnificent Yucca brevifolia, also known as Joshua Tree. They formed extensive woodslands in some areas of the northern Mojave, and young trees are marching northwards up into the southern valleys of the Great Basin. We didn’t find any apiphytic lichens on them, though we sure gave it our best!
Yucca longifolia, what a beaut. The longer you look at these as you wander throughout the landscape, you start to notice that they look kinda human, with the long leaves coming out like a giant headress.
My artistic rendition of the Yucca people.
Wondering what the soil crust communities were like in the northern Mojave? Well, first of all, let me tell you, they were there. And secondly, well…. you’re going to have to check out Part 2 that! (Coming soon).