Monday, May 8, 2017

Plant Speciation and distribution on the Llano Estacado




In the "rainy 1980's" Monahans Draw flooded every winter. On top of the flat Llano Estacado, floods slither across the land and do not become the proverbial roaring wall of water that is experienced in desert arroyos. Odessa's treated sewage water and floodwaters oozed well past its usual terminus at FM1788 (in the summer) or Midkiff Road (in the winter).

The 35 inches of rain that pounded down in 1986, caused floodwaters to meander all the way to "Pelican Lake" on the Garden City Highway at the Midland County line. For several winters, waters pooled up at Soda Lake, a playa southeast of town. When full, Soda Lake covered sixty acres and was six to eight feet deep. The water never evaporated for 10 years, as it was replenished for several years during the "rainy 80's."

The ranchers who owned the property where the lake was situated were quite gracious, granting limited access to local birdwatchers for fieldtrips. Not only was there a spectacular view (well, the best in Midland County anyway), but roadbuilders had dug caliche and chat from a section of the top. While this may not seem a good thing for local ecology, due to the ugly scar left behind, the walls of the excavation provided new habitat for birds. Although one species, Great Horned Owls, is found throughout the county, the "cliff" face is ideally suited their nesting needs. Every winter, at least one Rock Wren from the canyons of New Mexico finds the pit and remains for months. Abandoned caliche pits can be wonderfully diverse ecosystems as they age.

As a nine-year-old botanist-in-training, I found a Rue called "Dutchman's Breeches" and a Madder known as "Innocence" growing on a limestone outcropping on a ranch near Pelican Lake. Part of the fun of learning about flowers is the names and the stories that go with them. I loved these names (and the flowers themselves.) The Dutchman's Breeches truly look like miniature pantaloons!

For years that small outcropping was the only place I could find those species in Midland County, so I made yearly treks to check on their continued existence. Years later, I found both species growing on the Edwards Limestone ridge above Soda Lake 15 miles away. Innocence also grew along the spillway of the Interstate Pond.

Innocence and Dutchman's Breeches are common plants in their preferred habitat -- the rocky slopes of the Stockton Plateau, and the mesas and breaks on the east side of the Llano Estacado. Innocence can be found in gravelly limestone areas all over the Trans-Pecos and in New Mexico. Plants are often specialists, occurring only in specific locations with very detailed micro-environmental characteristics. Plant life covers the earth with a wonderfully detailed blanket -- and although it may seem cliched, knowing the woof of the fabric makes the blanket loved in the way of a two-year-old's security blanket.

I love this ugly brown desert in that way. As a child, I had countless days following my ornithologist mother, all the while developing an uncool, unmacho love of plants. It thrilled me to discover a new species to identify, to keep records of my findings, and to collect seeds to plant on our five acres on Neely Street. My folks would drive along county roads at five miles an hour, with me perched on the hood of the car, yelling "stop" whenever I saw a new plant to record. I found 150 wildflower species in one memorable day! My mother's birdwatching and my "botanizing" kept our family on the road over half of every year's weekends, celebrating what we learned about the landscape. As a young man I lived in Alaska, Colorado, Utah, Washington State, Oklahoma, Arkansas and California, but I returned home to West Texas to find myself.

Crawford's Ridge is a pocket of diverse botanical wealth within the larger mesquite brushland. Shortgrass prairie is found in the shallow soil on top of the ridge. Dotting the 100+ acres of the ridge top are small depressions that fill with rainwater for brief periods. These vernal pools have rich soil that creates another micro-environment. Midland County's native Salvia is a tiny annual with sky blue blossoms which only germinates after wet winters have kept these vernal pools damp for months

Shari Laidley discovered the first few specimens of this Salvia in Midland Draw, where floodwaters from town had pooled up in front of a riparian forest of hackberries and soapberries. Crawford's Ridge is the only location that local amateur botanists can locate this diminutive plant in the wetter years.

Elsewhere, I have found the tiny Salvia from south of Roscoe, to Big Lake, to Lubbock and back to Midland, so its range is sufficiently large to guarantee its survival. With such limited opportunities to fulfill its specific needs, the plant may seem rare, but truly is not. Had it been a large showy plant, it might have been mistakenly placed on the Endangered Species list because its particular needs would have taken several years of research to understand.

Ninety-nine percent of the life forms that share our existence on the Llano Estacado have not been thoroughly studied. To many biologists, the area is viewed thusly, "Why, heck, the Llano Estacado are a biological travesty, with farmland stripping the soil bare, except where overgrazed prairie has become brush-infested thickets. The place is a biologic armpit -- a rotten stinking no-good boring ugly desert." Corporate-funded academic research projects have no interest in most of the life forms found here. The tiny Salvia is not a weed, such as Bermuda Grass, for which a new herbicide is developed every few years.

Pure science, or knowledge for the sake of knowledge, is castigated severely in the public forum. (Remember Senator Proxmire's Golden Fleece awards?) Why spend money to research the sex life of a fly? Why spend money to research the micro-environmental needs of Salvia subincisa? Who in blue blazes cares about such inconsequential nonsense? Love is illogical, isn't it?

I love plants. I love picking at the tapestry of botanical life, picking up a tiny piece of the fabric and examining it with great care. I fall asleep clutching this allegorical blanket, seeing beautiful landscapes in my dreams -- "Oooh, this dream is starting at Crawford Ridge, and look, there is Salvia subincisa, so it must be May after a wet winter -- oooh that means so many wildflowers will be blooming! Oh, yes! It is a very good year!" No matter that drought continues to blister the landscape -- not in my dreams.

JoAnn Merritt also loves plants, and she is a plant finder extraordinaire. Over the years, she has added dozens of new species to the Midland County plant list. JoAnn was the first to discover the botanical wealth of Crawford's Ridge. She came whooping and hollering and yelling at the door of my house with two species she had not seen before, way back in the mid 1980's.

One was familiar to me: Paronychia, a funny, scabrous brillo pad, which I had seen on gravelly limestone hillsides all across West Texas. The other plant was new to me -- carrot leaves, carrot root, a green ball of wafered seeds. Definitely a carrot, but which? Cymopterus bulbosus to be exact -- Mountain Parsley in every day language. What a wonderfully strange plant, with its sweet, ferny smell and texture. Oh my, oh my!

When Ernie Johnson (the beloved baseball coach during the first 25 years of Lee High School's existence), and I worked on a Midland County Herbarium, I took him out to Crawford's Ridge. We again found a new species for the county in the vernal pools: Skinny-leaf Four-o-clock. As we sat on big boulders pushing out of the caliche pit, he idly asked about some tiny plants on the slope in front of us. Hunkering down with our rear ends in the air (the classic botanist posture) we compared two specimens. "They are different!"

Until that moment, we had thought there were only two species of Cryptantha (a genus of Borage with scorpoid cymes). The coiled buds unfurl as they bloom -- like Blue Curls, the big showy wildflower of sandy soils. We began examining every Cryptantha we could find, and before we knew it, we found seven species. Two specialized in limestone soils, two in clay soils, two in sandy soils, and one was a generalist, found in many habitats. My word! Why such diversity? Who knows? No other genus of plants in Midland County has undergone such speciation.

Years ago, I was sitting on a salmon fishing boat with Peter Islieb, the best-known ornithologist in Alaska. While we waited to unload our hold onto the tender, he talked about the differences in habits of several species of salmon, of which we caught five over a season. "Why are there so many different species?" I asked him.

Puffing on his pipe, he wearily squinted at me and said, "I do not know, but I see it as proof of God's existence. God encompasses everything unknown. We cannot truly understand time without end, or space without end. I know some people disagree with me, but when I look at the diversity of species filling many different niches, I see evolution at work. I see thousands and millions of years. I see that God has been around, carefully tweaking the genetics of creatures so they can survive varying conditions and changes through the eons. To me, evolution is proof of God. I see Him as a master craftsman, tinkering forever in His workshop."

I thought of that, when Coach Johnson and I found the seven Cryptantha. To find those seven species was truly a wonder. Each time the unknowable presents itself, I am awed. I feel the presence of a Power much larger than myself. When I learned that there are seven local species of Cryptantha fills my heart so much, it moved me to stand and lift my arms to sing wordless hosannas of gratitude for such an incredible world.


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