January 27, 2013

WAXWINGS
Birds aren't migrating through here headed north yet, but still the spring feeling has begun to diffuse through the entire bird community, arousing a certain quickening of spirit, a finer alertness, a sharper vivacity. This is visible in their more intense sociality, greater curiosity, and playfulness. Of course I'm being anthropomorphic here, but we humans and birds are both animals with the same distant ancestors, so why shouldn't the spring feeling that gladdens my heart these days not also be gladdening the heart of birds around me?

I thought those thoughts this week when a flock of maybe 20 medium-sized birds flew over the cabin and descended into the top branches of a nearby leafless Netleaf Hackberry still heavily laden with its crop of sweet-fleshed, red fruits. As soon as the birds landed, instantly each one began stretching for red hackberries, testing this one and that one before plucking the one that was just right. You can see a few enthusiastic foragers at https://www.backyardnature.net/n/13/130127wx.jpg.

Unmistakably, with those pointy head crests, black masks and dainty daubs of yellow, they're Cedar Waxwings. There's another slightly larger but very similar waxwing species, the Bohemian Waxwing, of northwestern North America, but that species never shows up this far south.

Thinking about how the waxwing flock's appearance set me to anthropomorphizing, I remembered how in earlier times great naturalists felt more at ease describing the behavior of other animals in terms of feelings shared with humans. For example, as a kid I collected most of the twenty-one volume series called Life Histories of Familiar North American Birds, published by the Smithsonian Institution between 1919 and 1968. Now that wonderful series ripe with anthropomorphic imagery is freely available online at http://www.birdsbybent.com.

In the 1950 edition describing the Cedar Waxwing, New Englander author Winsor Marrett Tyler wrote:

What a pleasure to see these birds so lustfully enjoying their hackberries, and for awhile to settle my mind in an intellectual ambiance which itself was like a carnation in the day's buttonhole.

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STYLONYCHIA
As spring comes on, water from the little Dry Frio River behind the cabin grows more and more populated with microscopic organisms, and my safaris through drops of river water become more interesting. This week's drop was animated with footprint-shaped, hyperactively fast-moving little beings that zipped across the microscope's field of vision with such velocity that I didn't even try to photograph one... until one turned up boxed inside a square pen formed by overlapping filaments of Spirogyra alga. Around and around he went trying to escape his Spirogyra cage until finally the brainless little creature seemed to pause to think, and I snapped the picture at https://www.backyardnature.net/n/13/130127s2.jpg.

In school we studied the famous Paramecium and I recall how it moved through water with the help of tiny hairs, or cilia, scattered across its body, and it was somewhat similarly shaped, and inside its body it contained similar bubble-like affairs which we were taught were food vacuoles. But Paramecium was a little more slender than what's in the picture, plus its cilia were evenly spread over the body's surface, while the hairs on our little being appear to be clustered at the ends and, unlike the even-lengthed hairs of Paramecium, of different lengths. Still, I figured that what I had was a member of the protozoan Class Ciliatea, a unicellular Ciliate, like Paramecium, so that was the starting point of my identification attempt.

With a bit of Internet browsing it became clear that here we had a member of the genus STYLONYCHIA.

Stylonychia species are carnivorous and prey mostly on other protozoans and bacteria. When starved, they turn to cannibalism. Learning this, and seeing how fast they dart through the water, I began thinking of them as top predators in my jungly drop of water, like juiced-up Bobcats on a scrubby hillside with lots of rabbit warrens.

Cilia on the body surface of Stylonychia sweeps food into an "oral groove" leading into its body through a "mouth pore" that ends in the gullet, at the bottom of which a sort of bubble forms with the food inside. This bubble with food inside becomes a food vacuole like those seen in our picture. As food vacuoles wander through the body of Stylonychia, organelles called lysosomes fuse with the vacuoles, emptying digestive enzymes into them. The enzymes break down the food into small pieces, which can then pass through the pores of the vacuole membrane as the vacuole travels through the cell supplying food to different parts of the cell body.

Cilia on Stylonychia not only sweep food into the body, but also -- unlike cilia on Paramecium -- they can be used like legs to move the body with a walking motion. In fact, our picture fairly matches one on the internet where the observer interpreted his Stylonychia as walking upside-down across the undersurface of his microscope slide's coverglass.

Stylonychia are described as very common inhabitant of ponds. I think the one in our picture is about 150 microns in length, a bit longer than the width of an average human's hair.

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DEVIL'S CLAWS
I first met the local species of Devil's Claws when Elvis the Neighbor's Billy Goat stood on his back legs with his front legs atop the fence to greet me as I left the cabin, but this time he wasn't baaing the way he usually was. When I went over to him I saw why he was so quiet: his muzzle seemed to be clamped shut with a muzzle apparently made of stiff wire or hard plastic. Along one side of the muzzle there was a boxlike, woody affair bristling with sharp spines, the longest of them entering Elvis's mouth, surely pricking the goat's lips and tongue. Who could have done such a mean thing to poor old Elvis?

Finally it began dawning on me that this thing around Elvis's mouth was too weathered and irregularly formed to be wire or plastic. Unwrapping it from around his muzzle I began recognizing it as the fruit of an interesting plant known by several evocative names, including Devil's Claws, Cow Catcher, Unicorn Plant, and the Spanish Cinco Llagas, which means "Five Sores." You can see two of these fruits attached to the top of the annual plant that produces them, found decaying on the ground, at https://www.backyardnature.net/n/13/130127pb.jpg.

Plants producing these fruits belong to the genus Proboscidea. Four Proboscidea species are listed for Texas, all with similar fruits, thus they are more easily distinguished by their flowers. Only one species is widespread and fairly common, so I'm assuming that that's the one we have here: PROBOSCIDEA LOUISIANICA, of the small Martynia Family, the Martyniaceae. The family is noted for the sticky, glandular hairs that cover its species' vegetative parts, and for the capsular fruits the species produce, with long, curved beaks. Most species in the family occur in the American tropics and subtropics.

Of course Devil's Claws' extraordinary fruits haven't evolved to make animals miserable, but rather to facilitate fruit dispersal. The long "claws" latch onto hairs of larger animals, and entrap the fruits on animal feet. You can see how one fruit hitched a ride on my boot at https://www.backyardnature.net/n/13/130127pc.jpg.

In that picture, notice how the capsule's top bears a crest consisting of numerous woody, jagged scales pointing upward. If the fruit were latched onto an animal's hoof, the scales would hurt with each step. Maybe the plant "wants" the animal to take a few steps, feel the pain, then remove the fruit before wandering so far that it might end up out of its preferred environment.

Devil's Claws' fruits seem to be too large for the animals that might transport them, such as deer. Also, the curved "claws" seem too long for the short fur on our area's animals. Some have suggested that Devil's Claw's fruits are anachronistic -- that they evolved to hitchhike on the much larger, hairier animals that roamed the Americas during the last million years, but now are extinct, such as Giant Ground Sloths.

In Mexico we've encountered another member of the Martynia Family, genus Martynia, which also produced woody capsules with curved claws, but those capsules and claws were much smaller. You might enjoy comparing our present fruits with those at https://www.backyardnature.net/mexnat/devlclaw.htm.

Mature Devil's Claw fruits have been used in basketwork in several indigenous American cultures.

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KING RANCH BLUESTEM
Though the last week has been warm enough -- the afternoon temperature on Thursday reached 77°F (25°C) -- I've been unable to find a new spring wildflower blossoming. And the two plants featured last week as the first blossomers of spring have disappeared, probably into the guts of deer. However, I did find a grass flowering, a tiny one huddled against the cabin's southwest side where it basks in afternoon sunshine and where it's clearly been nibbled on repeatedly by Minnie the Neighbor's Cow, who both cuts and fertilizes the grassy area around the cabin. You can see what a small, abused looking and homely little grass it is at https://www.backyardnature.net/n/13/130127gr.jpg.

Yet, the grass was indeed flowering and, at least up close, very prettily. You can see the tiny, purplish flowers with their stiff bristles, or awns, and with their fuzzy stigmas deployed to catch pollen at https://www.backyardnature.net/n/13/130127gs.jpg.

Hungry for spring flowers of any kind I was thankful to this humble little grass for being tough and optimistic enough to blossom in my cow-chomped grassy area here in January. I could hardly wait to identify it, and commit to memory this first flowering grass of the year. A distinctive fieldmark helping during the identification process is the collection of long hairs arising from bulging bases, as shown at https://www.backyardnature.net/n/13/130127gt.jpg.

The little grass turned out to be BOTHRIOCHLOA ISCHAEMUM var. SONGARICA, sometimes called Yellow Bluestem but in Texas usually referred to as King Ranch Bluestem. The species is native of central and eastern Asia, from Russia to India, but now occurs nearly worldwide in hot to warmish climates. In its native lands this grass is regarded as excellent for soil and water conservation because of its ease of establishment, rapid growth, grazing tolerance and high forage quality.

For this reason in the late 1800s and early 1900s the species was introduced into the US, and the variety songarica was created on the enormous and historic King Ranch here in Texas. Now the variety has spread beyond the King Ranch and is found widely in the US, mostly in the southern states. Mainly it occurs on soils developed atop limestone, and along roadsides and in weedy fields. And the remarks made about it in Shinners and Mahler's Flora of North Central Texas are typical of opinions about the grass in the US: They say it's "A pernicious weed crowding out native species."

The Institute for the Study of Invasive Species says on its webpage for King Ranch Bluestem that "... this dominating grass can create monotypic habitats which in turn reduce the diversity of insects, birds and rodents; which can further devastate natural ecosystems. Not only is the grass a threat but so is the insect that utilizes the King Ranch Bluestem as a host plant, the red streaked leafhopper. The red streaked leafhopper has been observed to carry a virus to sugarcane in Thailand, creating crop losses of up to 100% in some areas." That webpage is at http://www.tsusinvasives.org/database/king-ranch-bluestem.html.

So, the humble little plant singing of spring next to the cabin and filling my heart with gladness with its purple stigmas unfurled into the spring air is a pernicious weed, the bane of insects, birds and rodents, and diversity in general.

Such is the world, illusion piled upon illusion, and the heart hardly knows where to hang its hat.

*****

ALABAMA LIPFERN
Down behind the cabin where the little Dry Frio River runs beside a vertical limestone wall I've been putting off identifying a certain hand-sized, frilly little fern until it began producing spores. Lots of fern species are hand-sized and frilly looking, but normally they can be distinguished from one another by how they arrange their spore-producing parts. You can see some fronds growing from cracks in a limestone rock at https://www.backyardnature.net/n/13/130127fn.jpg.

The field mark I've been waiting for is seen on a frond's underside at https://www.backyardnature.net/n/13/130127fo.jpg.

Instead of grouping its spore-producing sporangia into dots or lines scattered in distinctive patterns across the undersurface of the leaflets, or "pinnae," this fern's sporangia are ordered in continuous lines beneath the curled-under margins of its pinnae. Not many fern species do this, and when I saw it immediately I knew we had a member of that group of ferns known as lip ferns, the "lip" being the pinnae edges partially folding over the sporangia.

This lip fern keys out to the Alabama Lipfern, CHEILANTHES ALABAMENSIS, a fairly common species within its ususual distribution area, which is mostly in regions of limestone outcrop in the southern Appalachians, Alabama and Tennessee and westward through Arkansas and Texas into northern Mexico's arid northern states.

You might notice that the pinnae margins on the fronds in the first picture are less scalloped than on those in the second picture. That's because fronds in the first picture were sterile, and pinnae margins on sterile fronds are slightly different -- more curvy -- from those on pinnae with spores tucked into their curved-under margins.

Having a dissecting scope handy I decided to look at this fern's sporangia, and saw what's shown at https://www.backyardnature.net/n/13/130127fp.jpg.

In that picture a curled-under pinna margin runs along the left side. To understand the items that look like segmented centipedes you must take into account how fern sporangia work.

Sporangia are tiny, baglike, more or less spherical affairs holding spores. Each sporangium of the Alabama Lipfern typically contains 32 spores; other species often have different spore numbers. To help the microscope spores disseminate into the wind, each sporangium has a crestlike ridge running across it -- the "centipedes" in our picture -- called the annulus. The annulus consists of cells (the segments in our picture) growing end-to-end. The cells are filled with liquid. When the spores inside the sporangia are mature and a dry day comes along, then the annulus' cells begin losing water and shrinking, exerting a pulling pressure, or tension, along the length of the annulus. Eventually this shrinkage of the annulus causes such tension across the surface of the sporangium that the sporangium violently splits open, sending spores flying.

In our picture the elongated annuluses are of sporangia that already have split open. The stretched-out annulus at the top, right in the picture bears part of the shattered sporangium covering beneath it. At the lower, left in the picture several sporangia not yet exploded are visible, looking like little snails.

So, the Alabama Lipfern is a fine little fern and I'm glad to have it as a neighbor. And I'm glad it's producing these sporangia, for that's yet another sign of spring.

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PERFORATED RUFFLE LICHEN
Bark of large, spreading, lower branches of our abundant Texas Live Oaks is likely to bear a crust of lichens -- mainly the Eastern Speckled Shield Lichens and Cartilage Lichens we've already looked at, but also less frequently occurring species. One of those less conspicuous yet not uncommon species is the foliose, grayish white lichen on a low live oak branch shown at https://www.backyardnature.net/n/13/130127li.jpg.

In that picture there's a second lichen, a darker, warty one, at the lower left in the picture, but we're not talking about that one.

Using the excellent but rather technical "Dynamic Key" at the LichenPortal.Org website at http://lichenportal.org, the main lichen in our picture was identified as the Perforated Ruffle Lichen, PARMOTREMA PERFORATUM, described as usually found on trees in open habitats but sometimes on rocks. It occurs here and there worldwide.

On other lichens we've seen that the craterlike growths visible on several of the lichen flakes, or thalli (singular thallus), are apothecia. Apothecia are reproductive structures produced by the fungal component of the lichen, and of course lichens are "composite organisms" composed of a fungus and an alga and/or a cyanobacterium. The apothecium's inner surface is covered with innumerable, microscopic, tubelike affairs called asci (singular ascus) stacked next to one another and containing spores (ascospores), which escape from the tubes' tops. When the fungal spores land in a good spot they germinate, their mycelium wrap around an appropriate alga or cyanobacterium cell, and begin growing into a lichen.

Many lichen species produce apothecia. However, the Perforated Ruffle Lichen's thalli bear something else less commonly observed on foliose lichens, and that's the slender, black, hairlike structures along the ruffled margins of the thalli. Those black hairs are called cilia and in lichen identification they are important because most lichens don't have them, but some do. Moreover, from species to species, the cilia's general appearance and disposition along the thalli margins vary greatly.

Most lichens reproduce more vegetatively via fragmentation than they do sexually, so I had always assumed that cilia on lichens bearing them would disintegrate and each tiny cilia particle would then form a new lichen. However, to form a new lichen asexually you need to have both fungal and algal cells bundled together, but lichen cilia are purely fungal in nature, consisting of bundles of fungal hyphae. I can't find an explanation of the purpose of lichen cilia, despite the fact that the ruffle lichen genus Parmotrema seems to regard them as desirable.

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SPINACH
The wooden sides of my raised garden beds are high enough to stretch plastic across them, thus converting the beds into coldframes. Consequently, despite our having had a couple of nights recently when the temperature dropped to 24°F (-4°C), currently I have pretty crops of coldframe-grown lettuce, Chinese cabbage, Japanese radishes, mustard greens, carrots, cilantro and spinach. In the big garden I'd planned to have much, much more at this time of year, but the leafcutter ants have caused me to completely abandon it. All that's left there is the garlic, which the ants don't seem to care for, and a large patch of defoliated turnips that shine in their sheared baldness. Sometimes the leafcutters even carve small flakes from the turnips' surface, pockmarking them.

On the day back in November when I discovered hoards of leafcutter ants branching out from the turnips into my other crops, I dug up what was left of the lettuce and spinach, and transplanted them into the raised beds, so that's what I'm enjoying now. The bok choy, beets, kohlrabi and other such winter crops were all destroyed by leafcutter ants. The leafcutters are staying away from the coldframes as long as I spray diesel around the coldframe bases. I slacked up a bit on that a while back and lost my cabbage crop before I realized what was going on. You can see a pretty little rosette of spinach leaves in a coldframe at https://www.backyardnature.net/n/13/130127sp.jpg.

When the warm afternoon sun stings my back and face and the land smells moist and rich, I like sitting beside the spinach, nibbling, admiring its taste and texture, visualizing all the spinach's antioxidants, vitamins, minerals, folate, betaine, protein and amega-3 fatty acids coursing through my body, blossoming from my stomach then coursing through my body in veins and capillaries, relieving a vitamin deficiency here, supplying a needed mineral there, the body consequently humming with satisfaction and well being, in harmony with the sunlight, and the springy feeling in the air. And I like to think about spinach's history, too, for it's fairly well documented.

They say that the Spinach plant originated in Iran and thereabouts. Arab traders carried it into India, from which it was introduced into China via Nepal. Getting to China was important because today China produces about 85% of the world's spinach, with the US coming in second at 3%.

Spinach reached Europe in 827 AD when Islamic traders introduced it into Sicily. By the 1200s it had filtered up to Germany. It got to England and France during the 1300s, and into the Americas a couple of centuries later. Nowadays the US is both an importer and an exporter of spinach, exporting more than it imports. Most of the US's imported spinach comes from Mexico but some is from Canada and China. In the US, California produces about three quarters of our spinach.

During my student years the Spinach plant, SPINACIA OLERACEA, was regarded as a member of the Goosefoot Family, the Chenopodiaceae, along with the Beet and the weed called Pigweed. But gene sequencing data now has found no difference between the Goosefoot and the Amaranth Family, so the Goosefoot Family with its Spinach and Beets has disappearead into the Amaranth Family, with its amaranths, the Amaranthaceae.

It's a beautiful thing on a warm January afternoon when the blue sky giggles occasionally with a Snout Butterfly fluttering by, or the spring song of a Cardinal or House Finch, and there are tender, innocent, wholesome spinach leaves to break off and eat with a slab of cornbread carried into the garden; a bite of spinach, a bite of cornbread, chewing in the sunlight, butterflies and birdsong, what a joy.

*****

FEATURED ESSAYS FROM THE PAST:

"Song Spirit," from the March 9, 2003 Newsletter, at https://www.backyardnature.net/n/p/030309.htm

"Songs Without Words," from the February 9, 2009 Newsletter, at https://www.backyardnature.net/n/p/090209.htm

*****

Best wishes to all Newsletter readers,

Jim

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