One of the most common questions people ask me about plants in the Big Bend Ranch State Park regards a small grass known as Fluffgrass. Their curiosity is understandable; over 20 years ago, when I was hiking in the park for the first time, a cold front bringing freezing temperatures and on-and-off rain passed. I wasn’t well prepared for this kind of weather so I was pretty cold. When I passed Cerro La Guitarra, without my glasses, I honestly thought there were patches of snow on the ground! This image, taken from a badly faded and color-shifted negative, records the scene.
- Fluffgrass on Guale Mesa
A closer inspection revealed that the white spots were a plant, but I had no idea what it was. Today I know it as Dasyochloa pulchella, the only species in the Dasyochloa genus. It is a perennial bunchgrass that forms small tufts just a few centimeters high with clumps of short, sharp-pointed leaves. Nobody seems to know much about it, or care much for it, but it is one of the most commonly occurring grasses in the Southwest.
This grass is readily noticeable, particularly when the sun is low and behind it, for it fairly glows, easily outshining everything else around. When fluffgrass drops its seeds, the translucent bracts remain on the plant, catching the light and giving the appearance of glowing.
Glowing Fluffgrass
The grass is regularly described as having “poor forage value.” When young and actively growing the plants are covered with a bluish-white down that may be objectionable to grazing animals. Later, when the plants mature, the leaves become harsh, wiry and sharp pointed. Livestock and wildlife generally avoid it; if you see it browsed, you know that times are hard.
What the animals don’t eat we can nonetheless enjoy, for this little grass is attractive at nearly every stage in its life cycle. It is particularly pretty when young for its bluish-green foliage is covered with a soft cottony down.
Young Fluffgrass Plant (Image ©Phillip Ruttenbur )
The nature of the down is not known – some experts claim it is composed of excreted mineral salts. Others say that it is made of carbohydrates. Whatever its composition, the “wool” is soluble in water and washes away with the first rain. Sometimes the down appears to be made of distinct fibers. At other times, the material looks much more amorphous.
- Amorphous Looking Fluffgrass Fuzz
The nature of the wool is not known – some experts claim it is composed of excreted mineral salts. Others say that it is made of carbohydrates. Whatever its composition, the wool is soluble and washes away with the first rain.
As fluffgrass matures, it loses its bluish cast and becomes a bright green.
Maturing Fluffgrass Plant
The inflorescence is one or two centimeters long and bears spikelets which are pale in color, sometimes striped with red, purple, or green. They are rather flattened and look a bit like small fans.
Fluffgrass Inflorescence
For me, fluffgrass has become one of the Chihuahuan Desert’s many little pleasures. The plant’s constantly varying appearance, bright glow in the winter, and preference for open areas where nothing else grows, makes it a welcome sight. Its ubiquitous presence is a constant reminder of life’s resilience, even in the most difficult of environments. Look for it the next time you hike in the Trans-Pecos. It’s worth your attention.
aneyefortexas 
What eats fluff grass? I’m doing a project for school about a food web and I can’t find what eats it. Do you know?
I have never seen any signs that Fluff Grass is being browsed by anything! Cattle certainly won’t eat it, nor will deer or other grazers. That said, I was out on a long horseback ride one day and discovered that my mount really liked the stuff. In fact, it was sometimes hard to get him to leave a nice patch. But that is the only example I’ve come across.
The plant is widely regarded as an indicator of overgrazed or otherwise abused pastures. Since nothing eats it, it is often the only thing left after the ranchers leave 😦
Sorry I don’t have any more information.
a desert tortoise does
Pretty grass, I don’t think it grows here around Tucson. Burn some of the ‘hairs’ in a flame chromatograph, that should answer the question of salt versus carbs.
Thanks for your comment and this great idea. I’ll do that the next time the plant greens up
and maybe post what I find.
Thanks for reading my blog, too.
Gary
Nice idea to feature such a widespread, but overlooked grass. It is common in the desert grassland areas of Abq, up into the foothills, but I’ve not seen it much north of town. I especially like it when it greens up for a short while, or the way it looks backlit by the sun on a slope when dormant. On your Guale Mesa photo, it almost looks like snow, since it is so dense!