JIM CONRAD'S
NATURALIST NEWSLETTER
Issued from the valley of the Dry Frio River on the
southern slope of the Edwards Plateau, northern
Uvalde County, southwestern Texas, USA

May 12, 2013

A MOURNING DOVE MOURNING
Nowadays male doves call from every direction. Maybe the most ubiquitous call is that of the invasive Eurasian Collard Dove with his slow, ever-repeating, moody hoo-HOOOO-hoo, the syllables short-long-short, like Morse Code for the letter R, which back in my ham radio days meant "roger," so all day long it seems to me that doves call down from light lines "roger, roger, Jim, roger, message received, roger, roger... "

But recently another dovish calling has mingled with the rogers, a mellow, in fact mournful, ooo-AH-ooo-oo-oo, or short-long-short-short-short, which in ham radio Morse Code means "wait" or "hold on... "

You can see a male Mourning Dove on an electrical wire in mid ooo-AH-ooo-oo-oo with his neck inflated, with a bit of iridescence further bringing attention to the neck, a part of the male's body the female seems to find fascinating, at http://www.backyardnature.net/n/13/130512md.jpg.

At a distance, Mourning Doves, ZENAIDA MACROURA, can be distinguished from our four other dove species by their long, sharp tails. Of the other four -- the Eurasian Collard, White-winged, Ground and Inca Doves -- only the Inca Dove's tail is long, but it's rounded, not sharp-pointed like the Mourning Dove's, plus the birds are much smaller, only 6.5 inches long to the Mourning Dove's 10.5.

*****

TRASHLINE SPIDER ON THE DEER FENCE
Tall wire fences to keep the deer out surround both of my gardens. For at least two weeks there's been a special type of orb web strung across one of a wire fence's square holes. What's unusual about the web is that across its center there's a vertical line of what looks like little bundles of odd-sized granular trash or debris. The web's silk strands are so fine that you can't see them unless the sun strikes them just right, so usually it looks as if the line of debris is suspended in mid air, normally vibrating in the wind. You can see the line of debris silhouetted against a dramatic sky, the line at first looking like one of the fence poles in the background, at http://www.backyardnature.net/n/13/130512c2.jpg.

A close-up of the line of debris -- technically known as the stabilimentum -- with a milkweed seed caught among the silk strands, is at http://www.backyardnature.net/n/13/130512c3.jpg.

In that picture, the topmost, oval item is the spider's egg sac. If you look a little below the picture's center you'll see the spider herself well camouflaged as debris where all the web's radiating strands come together. Much closer you can see legs and designs on the spider's abdomen, at http://www.backyardnature.net/n/13/130512c5.jpg.

That picture shows the tiny spider's undersides. A more illuminating view from the other side of the web displaying the spider's top and the unusual protrusion at the rear of the abdomen is at http://www.backyardnature.net/n/13/130512c4.jpg.

This is a commonly occurring and widely spread spider species, though it is so small and easily overlooked that it bears no good common name. It's CYCLOSA TURBINATA, distributed all across the US and southward as far as Panama. In Texas we have at least five species of the genus Cyclosa, and they all produce webs with such vertical lines of debris across their web centers, so the group of species in the genus are often referred to as trashline spiders. The trashlines consist of the sucked-dry carcasses of prey and sometimes egg bags. When disturbed, the spiders tend to shake their webs back and forth, maybe with the effect of causing larger animals about to crash through the web to back off.

Cyclosa species occur worldwide. Just in the Americas around fifty species are recognized, and probably there are many more. One reason trashline spiders are so widely distributed is that their young "balloon" from place to place -- they climb onto a perch, extrude a line of silk into the air, the wind tugs on the silk as if it were a kite, and when the silk is long enough and the tug powerful enough the spiderling releases its grip and travels on the wind.

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THE SOUTHERNMOST OHIO BUCKEYE?
The cabin I live in is in extreme northern Uvalde County, Texas. In fact, I'm so far northward that the northern county line runs through the laundry shed. About five steps north from my door brings me into Real County. That's significant because this week I was biking in Real County a mile or so north of the county line when the small tree turned up, whose flowers and leaves are shown at http://www.backyardnature.net/n/13/130512ae.jpg.

With those large, digitately compound leaves (leaflets diverging from the petiole top like digits on the hand) and large, erect panicle of yellowish flowers, you probably recognize this as a buckeye. It's the Ohio Buckeye, AESCULUS GLABRA. The reason it's significant that I found this in extreme southern Real County is that apparently Real County hosts the southernmost population of Ohio Buckeye. You can see the Ohio Buckeye's county distribution map at The Biota of North America Program website, with counties in which Ohio Buckeyes have been collected and identified highlighted in light green. 

On that map, the southernmost light green county in Texas is smallish Real County, and the Ohio Buckeye in the picture was in an especially sheltered spot not far from the southern county line. It's just possible that the tree in our photo is the southernmost of all naturally occurring Ohio Buckeyes.

Individual plants living at the extremes of their species' distribution area often diverge a little in various ways from "average" individuals at the population's center. That makes them of particular importance when we think in terms of safeguarding a species' genetic diversity.

In fact, our plants are so different from "average" individuals living at the species' center of distribution that in the past sometimes buckeyes in our area were recognized as an entirely different species: The Texas Buckeye, Aesculus arguta. Nowadays most but not all specialists agree that our trees deserve no more than varietal status, designating them as Aesculus glabra var. arguta. Texas Buckeyes are smaller in every way than regular Ohio Buckeyes, and tend to be bushier, with several trunks.

Thirteen to nineteen buckeye species are recognized, of which six or so species occur in North America. The species are fairly similar and are best distinguished by their flowers and fruits. A close-up of flowers from our tree is at http://www.backyardnature.net/n/13/130512af.jpg.

Notice that at least some of the stamens extend beyond the petals. That feature separates the Ohio Buckeye from some other species whose stamens are shorter and remain hidden inside the corolla. A close-up from below a flower showing better that blossoms bear four petals and that their stamens are of various lengths is at http://www.backyardnature.net/n/13/130512ag.jpg.

In our April 7th Newsletter we looked at the pink-flowered Mexican Buckeye, which isn't a "real" buckeye since it's in a different genus, though in the Buckeye Family. You can see how different our Ohio Buckeye is from the Mexican one at http://www.backyardnature.net/n/w/ungnadia.htm.

Ohio Buckeyes didn't occur in the part of western Kentucky where I grew up, so one day when I was a kid and a friend of the family traveled north into Indiana where buckeyes did grow, they returned with baskets filled with buckeye fruits. My mother was lucky enough to get a couple and she gave one to me, saying that if I carried it in my pocket I'd never get arthritis. I actually did carry it for a year or two.

Native Americans slow-roasted, peeled and mashed buckeye fruits to get a nutritious meal for making porridge. The roasting was important because otherwise the fruit and other parts of the tree are toxic, containing saponins. Still, traditionally minute doses of the seed were used internally in the treatment of coughs and asthma, and externally as a tea or ointment for arthritis and hemorrhoids.

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MESQUITES FLOWERING
At this time of year the Mesquites, PROSOPIS GLANDULOSA, lend a special touch of grace to the landscape with their elegant low, widely spreading shapes, the way wind and sunlight mingle so congenially inside their airy interiors, and the surprising emerald greenness of their new leaves. In this landscape otherwise dominated by dark, hard hues of oak and juniper. You can see the interior pleasing branching of a Mesquite in my backyard at http://www.backyardnature.net/n/13/130512mq.jpg.

Up closer you can see the Mesquite's twice-compound leaves structured like two feathers joined at their bases atop a single arching petiole at http://www.backyardnature.net/n/13/130512mr.jpg.

That picture also shows yellowish spikes of tiny flowers among the leaves. A close-up of some flowers whose petals are only about 1/8th inch long (3mm) is at http://www.backyardnature.net/n/13/130512mt.jpg.

It's interesting to note the hairiness at the tips and margins of the petals, possibly providing pollinators footholds as they wander over the blossoms looking for nectar. A feature of the flowers that surprised me when I saw the above picture is that many of the yellow, hotdog-bun-shaped, pollen producing anthers bear tiny, white, globular items at their tips. These items were so unexpected that I had to snip off a flower and look at its anthers under our dissecting scope. You can see what I found at http://www.backyardnature.net/n/13/130512mu.jpg.

The spherical items are glands. A study found that inside active glands secretory cells degenerate to release a protein carbohydrate exudate, which passes through openings of the gland's surface. The nutritious exudate spreads across the glands' surfaces attracting foraging insects, which provide the tree pollination service.

Here in the southwestern Texas Hill Country Mesquites aren't nearly as abundant as they are in drier landscapes to our south and west. There sometimes you see nearly pure stands of Mesquite stretching horizon to horizon. Here some landowners complain about Mesquite encroaching on their ranches, thinking of the tree as a scrubby, desert species. In fact, Mesquites may be invading our area because global warming is making our arid land even drier, enabling the vast Chihuahuan Desert to our west slowly to expand toward us. Maybe Mesquites are harbingering what's to come.

Old-timers here also know that Mesquite makes good firewood, is excellent for making charcoal, and that find fence posts can be made from them.

Mesquite leaves contain tannins, so traditionally they've been dried and made into powder to apply to cuts and scrapes to cut down of inflammation and to pucker cut veins so they don't bleed so much. Mesquite leaf tea has been used against sunburn, rashes, bites and other such skin irritations, and can be gargled for a sore throat and mouth sores.

*****

TWOLEAF SENNA FLOWERING
A common wildflower blossoming now in grassy spots and elsewhere where the soil is thin atop limestone is the 15-inch (40cm) perennial herb shown at http://www.backyardnature.net/n/13/130512ca.jpg.

Lots of wildflowers nowadays bear yellow-orange blossoms like these, but up close you notice that this plant's leaves are unusual. They're compound, with each leaf consisting of only two stiff, slender leaflets joined at their bases forming wide Vs. A close-up of two leaves is shown at http://www.backyardnature.net/n/13/130512cc.jpg.

Up close the inch-broad flowers (2.5cm) immediately bring to mind flower types we've often seen in the Yucatan, as you can see at http://www.backyardnature.net/n/13/130512cb.jpg.

Besides the yellow-orange color, what's notable is that the corolla is almost radially symmetrical, but not quite; it's barely bisymmetrical, with some petals a little larger than the others. Moreover, the nine or ten stamens -- looking like little yellow bananas on stems in the corolla's center -- are different sized as well, some so small and poorly formed that they're sterile.

These field marks point us toward the big Bean Family genus Senna, of which maybe 300-350 species are recognized, and in Mexico we've seen our share. Though Senna leaves always are compound, normally they're divided into many leaflets, so this species' mere two leaflets is something very special. In fact, that feature gives the species its main common name, which is Twoleaf Senna. It's SENNA ROEMERIANA.

Twoleaf Senna as well as many other senna species are regarded as medicinal, the most common usage being that of serving as a laxative. Tea made by boiling the plant irritates the lining of the colon causing "peristalsis and bowel evacuation," as they say. Several commercial laxatives are based on sennas, the best-known in the US probably being Black Draught.

As you might expect from a harsh irritant of the colon, in high doses Senna extract is toxic. In fact, in these parts sennas are mostly thought of as dangerous for cattle, goats and horses to eat, symptoms including diarrhea, weakness, dark urine, and death.

Twoleaf Senna is endemic to arid northeastern Mexico, southern New Mexico, most of Texas and a tiny bit of Oklahoma.

*****

PINCUSHION DAISIES
At roadsides in some of the driest, thinnest, most unaccommodating-looking dirt imaginable, a certain 15-inch-tall (40cm) plant has been catching my attention for some time. It consists of nothing but a spherical cluster of tightly packed blossoms, for it's a member of the Daisy or Composite Family, atop a stiff, slender stem arising from a meager rosette of deeply lobed, dandelion-like leaves. A typical plant is shown at http://www.backyardnature.net/n/13/130512gl.jpg.

I've been waiting for ray flowers to develop before I took a closer look, but finally I noticed that butterflies frequently visit the rayless heads, apparently taking nectar from mature flowers. It turns out that this is one of those rare Daisy Family members lacking petal-like ray flowers, and whose cylindrical disc flowers are packed into a spherical head. A close-up of a flower head is at http://www.backyardnature.net/n/13/130512gn.jpg.

In that picture you see many cylindrical, purplish-red disc flower corollas packed side by side. From their tops emerge fuzzy, pollen-collecting style branches with stigmatic surfaces, and at the base of the corollas arise pale scales tipped with needle-like bristles or "aristae," which constitute the pappi atop the developing fruits, or cypselae. The most commonly encountered pappi type are white hairs, like those that become the fuzz atop parachuted dandelion fruits, and many Daisy Family members have no pappi at all, so such pappi as these are a little unusual.

A closer look at the basal cluster of lobed leaves can be had at http://www.backyardnature.net/n/13/130512gm.jpg.

With so many unusual features, this wildflower was easily determined to be a species going by several common names such as Pincushion Daisy, Rayless Gaillardia, Fragrant Gaillardia and Perfumeballs. It's GAILLARDIA SUAVIS, especially adapted to calcareous and sandy soils of prairies, desert scrub, and juniper woodlands like ours. They occur in arid northeastern Mexico and in the US from Texas north to Kansas.

Another unusual feature about Pincushion Daisies I didn't know about until I read it is that many individuals of the species do indeed produce petal-like ray flowers causing the flower heads to look like those of typical daisies. In fact, most pictures of the species on the Internet show heads with ray flowers. All the ones I've noticed are rayless. Maybe it's because of our severe drought, or maybe our local ones simply tend to not produce rays.

Also I was surprised by the Pincushion Daisy's other common names alluding to the flowers' fragrance. During my visits I've not noticed any aroma. Maybe it was too windy or maybe I just stayed upwind from them. But I read that they smell of gardenia. Certainly butterflies are attracted to the heads.

*****

PRAIRIE PHLOX
Down inside knee-high grass in patches of prairie here and there nowadays you can find the foot-tall, purple-flowered wildflower blossoming shown at http://www.backyardnature.net/n/13/130512px.jpg.

With corollas of that color and that particular shape -- slender tubes topped by five horizontally spreading lobes -- and with two leaves per stem node (opposite leaves) anyone halfway familiar with North American wildflowers or common garden plants will recognize this as a phlox, a member of the Phlox Family, the Polemoniaceae.

In our area we have two common phlox species. The other species, the Goldeneye Phlox, displays a conspicuous golden eye at the blossom's center, which our species doesn't. The species in the picture is about equally known as the Prairie Phlox and the Downy Phlox. It's PHLOX PILOSA, occurring throughout most of the eastern US, though absent from New England and the Appalachians. It's most common in the westernmost states of Eastern North America.

A pretty picture suggesting why one name of the plant is Downy Phlox is shown at http://www.backyardnature.net/n/13/130512py.jpg.

The long hairs on the calyx and long, slightly curved corolla tube are soft to the touch. A longitudinal section of a blossom showing that the hairs are gland tipped, and that the stamens -- typical for the genus Phlox -- are inserted on the corolla tube at different levels, is at http://www.backyardnature.net/n/13/130512pz.jpg.

Huron Smith's 1928 publication Ethnobotany of the Meskwaki Indians, dealing with the Fox Tribe, reports that Prairie Phlox roots were used as "love medicine." In other cultures, traditionally a tea of the leaves was used externally to treat eczema.

*****

TEXAS NEEDLEGRASS
Behind the cabin nowadays a certain two-ft-tall grass (60cm) calls attention to itself by its abundance and by the way sunlight slanting in at dawn and dusk accentuates the grass flowers' long, stiff "awns," as displayed by a group leaning through the deer fence around my raised beds at http://www.backyardnature.net/n/13/130512st.jpg.

Each flower's developing grain, or caryopsis-type fruit -- of which there's only one per flower, or spikelet -- bears an awn, and those long, stiff, slender awns are the special thing about this grass, making it easy to recognize. You can see how the needlelike awns stand out when you look closely at a grass's open panicle at http://www.backyardnature.net/n/13/130512su.jpg.

A single spikelet showing a developing grain with its awn arising from a neck-like "crown," and the grain subtended by two slender, sharp-pointed, purplish glumes, can be seen at http://www.backyardnature.net/n/13/130512sv.jpg.

In that picture, notice how the base of the awn atop the grain twists. As grains mature and the grass dries out, the awns twist more and more, causing the awns to bend into odd shapes. You can see an older inflorescene with awns beginning to crook at http://www.backyardnature.net/n/13/130512sw.jpg.

The awns' twistiness increases as the awns dry out but decreases when they are moistened. This causes the awns constantly to be changing their shapes, sometimes so fast you can see the movement. When a grain falls to the ground and undergoes humidity changes, the moving awns catch on nearby objects and in a somewhat haphazard fashion assist the grain in screwing itself into the soil.

In much of the southern US this interesting grass used to be a dominant species but now it's mainly found in Texas and contiguous states, and arid northeastern Mexico. It goes by several common names, including Texas Needlegrass, Texas Wintergrass and Texas Speargrass. It's NASSELLA LEUCOTRICHA. In literature of my younger days it was placed in the genus Stipa, and many sources still refer to it as Stipa leucotricha. About 116 species of Nassella are recognized, with the evolutionary center assumed to be South America, since that's where most species occur.

Texas Needlegrass not only produces regular florets which open to expose their stamens and stigmas for pollination -- the common condition of most flowers and known technically as "chasmogamy" -- but also "cleistogamous" ones, which remain closed and thus are not cross-pollinated. Studies show that the drier the soil, the more cleistogamous florets are produced. Since we're experiencing an extreme drought here I figured I could find cleistogamous florets on our grasses, but I couldn't.

In southwestern Texas this is an important grass, often found in prairie patches, brushy areas, roadsides and disturbed spots. It produces good forage for livestock during the winter, though the awns on the grains at this time of year can injure livestock mouths, sometimes having to be removed surgically.

*****

JELLY EAR FUNGUS
Many folks don't pay attention to the fact that each species of tree they plant around their houses has its own specific needs. Someone who once lived in the cabin I'm occupying was like that, for they've planted several garden flowers, bushes and trees that might make sense out East where it's much rainier than here, but not in our area at the edge of the vast Chihuahuan Desert. For example, they planted Sycamores around the house, even though in nature Sycamores usually occur next to streams. Consequently two summers ago when our long-term drought was especially bad, the Sycamores died. The trunk of one still standing leaflessly beside the cabin now is being colonized by the special kind of brown, gelatinous fungus shown at http://www.backyardnature.net/n/13/130512fu.jpg.

A close-up of a cluster of the fungus's spore-producing bodies is shown at http://www.backyardnature.net/n/13/130512fv.jpg.

Two days of dry, hot wind after the above picture was taken, the same cluster was photographed, and you can see how its appearance had changed by then at http://www.backyardnature.net/n/13/130512fw.jpg.

Soon after that picture of the dried-out fruiting bodies was taken, a small shower came through, and the next morning the same fungus was brown and jelly-like again. This is a species able to "go into suspended animation" when it gets dry.

But the species is common not only in arid lands but also in temperate regions worldwide, where it grows on both dead and living wood. It's AURICULARIA AURICULA-JUDAE, which, when I was a kid, mushroom field guides matter-of-factly identified as Jew's Ear Fungus, reflecting the binomal first published in 1888 (the Latin auricula-judae meaning "Judas's ear"), but which in our more politically correct times now usually is called Jelly Ear.

Whichever name we use, this is a good fungus to know not only because it's so widely occurring and easy to identify, but because it's edible and medicinal. The Chinese use it in their hot and sour soup. The fungus doesn't have much taste of its own but it soaks up the flavor of whatever it's cooked with. In America's pioneer days sometimes the moist little "ears" were covered with syrup, let to dry, and eaten in the winter as candy.

Both in the Orient and the West Auricularia auricula-judae has been used medicinally in various ways. In China it was used especially against hemorrhoids and as a general body strengthener. In fact, modern research finds that extracts of the fungus display certain anti-tumor, hypoglycemic, anticoagulant and cholesterol-lowering properties. Mushroom guru Tom Volk at the University of Wisconsin mentions cases of internal bleeding from particularly sensitive people who accidentally ate too much Chinese hot-and-sour soup combined with stir-fry containing this fungus. There is some evidence that regular ingestion of Auricularia in small doses can help prevent strokes and heart attacks.

*****

FEATURED ESSAYS FROM THE PAST:

"On Changing the Textures of Life," from the September 26, 2004 Newsletter, at http://www.backyardnature.net/n/p/040926.htm

"On Living Gracefully," from the August 29, 2004 Newsletter, at http://www.backyardnature.net/n/p/040829.htm

*****

Best wishes to all Newsletter readers,

Jim

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

Visit Jim's backyard nature site at http://www.backyardnature.net