September 29, 2013

BAR-CODED HAWK WITH WINDOWS
It's that time of year when hawks are wandering, showing up where they're not usually seen. Since my vision isn't so good I photograph any hawk that flies over, then look at it on the computer screen. You can see one such picture at https://www.backyardnature.net/n/13/130929hw.jpg.

Michael Overton's checklist "Birds of Uvalde County, Texas" lists 20 species of "Kites, Hawks, Eagles & Allies," and some of those don't turn up in most of the US, such as the Zone-tailed and Short-tailed Hawks and Common Black-Hawk. The one in our picture looked very familiar but without comparing field marks with those in the field guide I didn't want to make a snap judgment.

Several hawk species display banding similar to this hawk's. For example, the Short-tailed hawk's tail banding is similar, except that its two inner bands are narrower than the outer one, which isn't the case here. Also, the wings of Short-tails don't display nearly as many conspicuous narrow bands as appear on this one.

It turns out that the hawk in our picture was the common one around my hermit camp back in southwestern Mississippi, the Red-shouldered Hawk, BUTEO LINEATUS. One of the Red-shouldered Hawk's field marks consists of the "translucent windows" at the base of the wings' outermost primary feathers, and those windows show nicely in our photograph. When the sun isn't shining above the birds, the windows aren't as conspicuous.

Michael Overton lists Red-shouldered Hawks as uncommon at all seasons in Uvalde County, and it's true that the distribution map in my field guide shows that we're exactly on the Red-shouldered's westernmost point of distribution. Several hawk species occur coast-to-coast in North America, but Red-shouldered Hawks are mainly Eastern, with an isolated, or "disjunct," population in coastal California. I associate Red-shouldered Hawks with swamps and river floodplains with tall trees, none of which we have here at the edge of the Chihuahuan Desert. Our bird must have been feeling adventurous to penetrate this far into arid land.

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AGARITA'S YELLOW DYE
While digging a trench for some buried pipes I broke a bush's branch whose wood was bright yellow beneath dark brown bark. You can see it at https://www.backyardnature.net/n/13/130929dy.jpg.

The bush was the Agarita, BERBERIS TRIFOLIOLATA, which is abundant here and easy to identify with its leathery, spiny-margined, evergreen leaves. Our Agarita page is at https://www.backyardnature.net/n/w/agarita.htm.

When I whittled a handful of woodchips from the stem into a bowl of water, immediately the water yellowed, as shown at https://www.backyardnature.net/n/13/130929dz.jpg.

Sitting overnight, the yellowness didn't much intensify, so it seems that whatever causes the yellow color is highly soluble in water, and therefore probably it would tend to run if used as a dye.

Still, I read that the pioneers did use Agarita dye, and that during World War II dye from Agarita roots was used as one hue of color-coded parachutes. Parachutes for different drops were color-coded to indicate whether they contained equipment, supplies, food, or ammunition. Texas farmers contributed large amounts of Agarita roots.

The pioneers knew how to use "mordants" to make their homespun textiles retain natural dyes better. Mordants include tannic acid, alum, urine, chrome alum, sodium chloride, and certain salts of aluminum, chromium, copper, iron, iodine, potassium, sodium, and tin. Referring to her use of Texas Persimmon as a dye, Deb McClintock here in the Texas Hill Country writes, "Typically I use 12% alum sulfate to WOF (weight of fiber)."

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GLOBECHERRY
In the garden a certain plant gave the impression of being a member of the Black Nightshade/Tomato/Potato Family, the Solanaceae, because of its simple, somewhat thin leaves on slender petioles, and irregularly wavy blade margins. At first I thought it might be one of the black nightshades. You can see it at https://www.backyardnature.net/n/13/130929ph.jpg.

However, on hands and knees I saw that the fruits weren't at all like the miniature tomatoes produced by black nightshades, but rather were inflated bladders, as shown at https://www.backyardnature.net/n/13/130929pi.jpg.

Tearing away one side of a bladder, a little "tomato" was exposed, shown at https://www.backyardnature.net/n/13/130929pj.jpg.

Maybe you know the Mexican plant called Tomatillo, which produces sweet, firm, green tomato-type fruits surrounded by bladdery husks like those in the picture. Tomatillo fruits are much used in salsas. If you know the wildflowers called ground cherries, they also bear similar bladder-surrounded tomatoes. Both ground cherries and tomatillos are members of the genus Physallis in the Nightshade Family.

So, the fruits of our garden species are typical of those produced in the genus Physallis . However, the flowers of Physallis species usually are thumbnail size, yellow and with "rotate" corollas like wide-brimmed sunhats. Our plant doesn't bear such blossoms. Our plant's flowers are much smaller than any Physallis flower I've seen -- about 1/8th inch (4mm) -- and they're structured very different. You can see one, shaped more or less like a blueberry flower, at https://www.backyardnature.net/n/13/130929pk.jpg.

Our garden plant is MARGARANTHUS SOLANACEOUS, identified in books as Netted Globecherry, occurring in the southern parts of Texas, New Mexico and Arizona south through much of Mexico, with outlying populations in Cuba, Curaçao, Costa Rica and Honduras. It's such a peculiar plant that it's the only species in the genus Margaranthus.

Physallis fruits are often edible and good tasting, but black nightshades are poisonous. I find no reference to anyone eating fruits of Margarathus, and I, mindful of how certain members of the Nightshade Family can kill you, am not going to test them.

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SAND AMARANTH
Last week we looked at a Sand Sunflower whose seeds had been introduced in a truckload of sand dumped in the backyard of the red cabin in the valley where I spent the winter. Next to that pretty sunflower grew yet a second species I've not seen elsewhere in the valley, but this waist-high plant was about as scraggly, colorless and weedy looking as you can imagine. You can see it at https://www.backyardnature.net/n/13/130929am.jpg.

Up close you find that the tiny flowers arranged in spikelike inflorescences at branch tips are unisexual, and that male and female flowers occur on separate plants. Male flowers consisting of only five stamens with bright yellow anthers and five sharply pointed tepals -- which are undifferentiated petals and sepals -- are shown at https://www.backyardnature.net/n/13/130929ao.jpg.

A clutter of female flowers with their white, fuzzy stigmas exposed, and a tiny oval fruit only 1/16th inch or 1.5mm high (at the picture's lower, left), are shown at https://www.backyardnature.net/n/13/130929an.jpg.

Such very small, unisexual flowers without colorful corollas are typical of the Amaranth Family, the Amaranthaceae. And within that family, at least if you're in North America, if you have a herbaceous plant displaying only one leaf per stem node (alternate arrangement) and the flowers are unisexual -- all as seen with our sandpile plant -- you know you have a genuine amaranth, a species in the genus Amaranthus. However, about 70 amaranth species are recognized, with some 38 occurring in North America, so to know exactly what you have you must "do the botany."

It turns out that our sandpile amaranth is a fairly distinctive species and easy to key out in the online Flora of North America at http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=101257.

Its main field marks are its spinelessness, its unisexual flowers on separate plants (plants dioecious), female flowers with five tepals only about 1.5 mm long, and the utricle-type fruit similarly small, only about 1.5 mm tall.

Very appropriately accompanying our Sand Sunflower on our sandpile, this is the Sand Amaranth, AMARANTHUS ARENICOLA, the species name arenicola meaning "growing on sand."

Sand Amaranth is native to the central and southwestern Great Plains, from Texas to Nebraska and South Dakota, and occasionally is introduced into other parts of North America and Europe.

Several amaranth species produce shiny, hard, small seeds that in various cultures have been popped like popcorn or ground into amaranth flour for breads, and some amaranth species provide leaves that can be cooked as a potherb. However, Sand Amaranth's seeds are exceptionally small, only about 1/32nd-inch across (1mm) so collecting them would be very tedious work, and the plants' leaves are narrow and small. However, seed-eating songbirds would find the black, shiny seeds about perfect to peck at.

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FALSE CLOAK FERN
Probably during a flashflood a few thousand years ago, a leg-deep stratum of rounded limestone pebbles was washed into an arroyo, in arid country an arroyo being a normally dry stream or gully. Over time the deposited layer dried out and the sandy, silty, calcium-carbonate-rich matrix between the pebbles cemented the mixture of pebbles, sand and silt into a massive formation of the composite rock type known as conglomerate.

Conglomerate is hard rock but nowadays a modern-day arroyo is eating away at the layer by undercutting it. Floodwater erodes softer rock from below the conglomerate, then big chunks of it fall into the streambed from their own weight. This results in a vertical, waist-high wall of conglomerate on one side of the arroyo. And in a crack in the solid face of this limestone-based conglomerate a fern grew I'd not seen before. It was unusually small, the fronds no longer than three inches (8cm), as shown looking down on the fern emerging from the conglomerate wall at https://www.backyardnature.net/n/13/130929ar.jpg.

Notice that some of the fronds are green, while others are shriveled into dry wads. Moreover, the shriveled ones have curled in such a way that the fronds' chalky-white undersurfaces face outwards, surrounding the green upper surfaces. The chalkiness is caused by a special kind of dense, short hairiness known as farina, the word farina usually being applied to flour, so the fronds' undersurfaces are "powdery white, like flour."

The green fronds are sterile, but the shriveled ones are fertile, producing spores. That's good because without the spores I'd be unable to identify the fern. A close-up of a shriveled fern wad displaying the spore arrangement on the frond's undersurface is at https://www.backyardnature.net/n/13/130929as.jpg.

There you see that the sporangia -- the brown, granular little bags holding spores -- are lined up along the frond margins. Many ferns produce their sporangia scattered in distinctive groupings across the frond's undersurface. In rainier eastern North America the sporangium arrangement shown in the picture is mostly found among a handful of ferns specializing in dry cliff faces -- cliffbrakes and lip ferns. Here in southwestern Texas, so far about half the ferns species I've found are lip ferns, genus Cheilanthes, so I figured that this was yet another lip fern species, our fifth.

However, this little fern doesn't match any lip fern possibly found in our area. Fortunately, the fern section of the online Flora of North America is finished, so I could figure out what we had. It's a genus I'd never heard of. It's ARGYROCHOSMA DEALBATA, usually known as the Powdery False Cloak Fern or False Cloak Fern. "Real" cloak ferns are members of closely related genera, where this fern was relegated until the genus Argyrochosma came into existence in 1987.

Powdery False Cloak Ferns occur spottily on calcareous (limestone) cliffs and ledges mostly in the south-central US states -- Missouri and Kansas south to here in southwestern Texas.

What a pleasure to meet such an obscure, seldom encountered little fern that's so highly specialized for living on calcareous cliffs and ledges!

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GRAZER GRASS
Much of our part of the Dry Frio River Valley is occupied by large fields behind tall deer fences and owned by a huge ranch. The fields are planted with robust, fast-growing grass that reaches waist high. The mowed grass is formed into large, wheel-like bales, removed and eventually fed to cattle. Despite this summer's heat and drought the grass grew astonishingly well, and a field sowed this spring and cut in the summer now is knee high with new shoots sprouting from the grass's base. I've been curious as to what kind of grass this is. Local folks call it Grazer Grass, but that term isn't mentioned on the Internet. I've itched "to do the botany," but all the plants have grown beyond reach behind the fence, and in this country the wise don't trespass a single foot onto ranchland.

However, one plant of the jillions in the field somehow came up so close to the fence that when it flowered this week I could reach through the fence and get some blossoms. You can see the plant beside the field of knee-high sprouts issuing from stems cut a month or so ago, the camera held inside the fence, at https://www.backyardnature.net/n/13/130929so.jpg.

One field mark that shouldn't be forgotten when dealing with grasses is the "ligule," situated where the blade meets the stem. Some grass types don't have them, others have ligules looking like little cellophane walls between the blade and the stem, and still others are toothed, or composed of hairs. You can see what this grass's ligules looked like at https://www.backyardnature.net/n/13/130929sr.jpg.

The grass's inflorescence is a congested panicle looking somewhat like a corn plant's tassel of emerging male flowers, as shown at https://www.backyardnature.net/n/13/130929sp.jpg.

Up close you see that at least some of the florets are affixed with slender, sharp, needle-like "awns" that tend to curve and twist, as shown at https://www.backyardnature.net/n/13/130929sq.jpg.

At tips of inflorescence branches the spikelets do something special that's diagnostic. You can see what happens at https://www.backyardnature.net/n/13/130929ss.jpg.

There you have three spikelets. The large, fertile one in the center with a brown, bent awn at its tip is accompanied by two smaller male spikelets, one on each side. Of course only the fertile one produces a grain, the male ones only producing pollen.

So, these are all features of Sorghum bicolor, one of the most important cultivated plants on Earth, because of its widespread use in tropical and subtropical areas as food for animals and humans, and for ethanol production. It's an African plant generally known as Sorghum, Forage Sorghum, Milo or a number of other names. Sorghum as a crop originated as far back as 3,000 years ago, and many cultivars have been developed.

Because our flowers don't seem to be producing the large, brown, exposed grains that mature flowers of regular Sorghum are known to produce, I suspect that our plant is a hybrid between Sorghum and Sudan Grass, Sudan Grass itself being both a member of the genus Sorghum, and a hybrid. It's Sorghum × drummondii.

The Sorghum x Sudan hybrid is much marketed as displaying "the regrowth capability of sudangrass but the yield potential of forage sorghum." The hybrid manifests itself in several distinct cultivars, such as the BMR 6-gene and BMR 12-gene types.

Traditional taxonomy fails to provide concise names for important cultivars such as this one. Sugar Grazer II is the commercial name of one such cultivar.

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COMMUNING WITH MUSTARD GREENS
Two days after sowing mustard greens in our new raised beds, already little sprouts were up, each plant issuing its first leaves, the cotyledons, shown at https://www.backyardnature.net/n/13/130929mu.jpg.

The largest seedling there is only 3/16ths-inch across (5mm). They're sown too close together because as they grow I thin out the smaller ones, eating them. It almost looks as if each seedling bears four cotyledons, but really each single leaf is notched at its tip, causing it to look like two.

It's amazing how clean and shiny each little plant is, arising from dark, musty, crumbly soil.

On the seedlings' first morning, for a good while I sit next to the beds just looking at the plants, letting impressions such as that about clean, shiny plants arising from dark, musty, crumbly soil, seep into me. It feels as if Nature is imparting some kind of wisdom or statement of confirmation to me, something I can't put my finger on, but something obviously powerful that roots me in a nurturing, motherly kind of way.

As the moment develops, it grows clear that those shiny little cotyledons are the plants' solar panels being deployed to gather sunlight energy for fueling the next spurt of growth, the issuing of leafy stems from between the cotyledons. I visualize the Sun 93 million miles away erupting energy that floods through space, rains onto Earth, and a tiny, tiny, tiny but absolutely necessary and expected bit of that energy falls onto these cotyledons exactly where and when it's needed, some splashing on me, too. Green plants, blue sky, dazzling sunlight, me sitting on brown soil that feels cool and moist, the morning's fresh smell, dew on grass, things functioning perfectly.

And I, too, am fueled by sunlight. For, the energy that keeps me moving and thinking comes from plants I've eaten, who gathered their energy directly from the sun. Even the eggs and cheese I eat brings into me sunlight energy originally captured by plants who produced grain and herbage the hens and cows ate.

The Sun gushes energy, and Life on Earth blossoms, me along with it.

On a moist, fall morning, blue sky, baby mustard plants, old bald fellow sitting on the ground, sun blazing, sunlight flooding, the dawning insight that as the Sun is just one star in an unremarkable corner of a mediocre galaxy randomly placed among 176 billion other galaxies in the Universe, some kind of higher-level emanation and reception is taking place right here next to the mustard plants, a crystallizing spiritual insight structuring itself like photosynthesis and rooted in the Big Bang, and whatever accounted for that.

What a thing that baby mustard greens facilitate such thoughts, yet, in the end, I'll simply eat them, and proceed to the next moment.

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FEATURED ESSAYS FROM THE PAST:

"On Really Seeing a Seed" from the August 17, 2003 Newsletter, at https://www.backyardnature.net/n/p/030817.htm

"Antelope or Elephant?" from the April 4, 2010 Newsletter, at https://www.backyardnature.net/n/p/100404.htm

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Best wishes to all Newsletter readers,

Jim

All previous Newsletters are archived at https://www.backyardnature.net/n/.