NATCHEZ NATURALIST
NEWSLETTER:
from the woods near Natchez, Mississippi, USA

January 25, 2004

SAVANNAH SPARROWS
Down near the pond we have a second-year abandoned field covered with weeds, not yet claimed by Loblolly Pines and Broomsedge. For a while I've been noticing sparrows there with heavily streaked breasts, spending most of their days foraging on the ground for weed seeds. As soon as I'd appear they'd quickly take cover inside a blackberry thicket at the edge of the woods. They'd perch there preening and gazing at me, an easy confidence reflected in their eyes, for they knew how perfectly the spiny blackberry canes protected them. Seeing the birds' heavily streaked breasts, I'd been assuming that they were Song Sparrows, which are common in nearly any suburban setting, and abundant here. However, this week I took a closer look at them with binoculars, just for the pleasure of seeing them, and for the first time saw that their "eyebrows" were yellow near their beaks. Song Sparrows never have yellowish eyebrows.

They were Savannah Sparrows, PASSERCULUS SANDWICHENSIS, and that just tickled me. Savannah Sparrows aren't really rare, but usually they go unnoticed because of the general tendency to overlook "little brown thingys" quietly living their lives. You can see this bird's yellowish eyebrows at http://members.tripod.com/caddobirds/images/30Nov02_SavannahSparrow_RM.jpg

On the USGS's Savannah Sparrow page you can view other pictures, as well as the species' summer distribution map (BBS Map link) and winter distribution (CBC Map), at www.mbr-pwrc.usgs.gov/id/framlst/i5420id.html

The distribution maps show that during the summer Savannah Sparrows don't make it much farther south than northern Kentucky, but during the cold months they are densely concentrated in our area, especially in southern Louisiana. During summers the species nests in open, wet grasslands such as tundra, mountain meadows and grassy dunes, so probably our second-year abandoned field next to Sandy Creek feels comfortable enough. My Audubon "Master Guide" says that "Dense cover is essential to this bird. It flies a short distance when flushed, quickly dropping out of sight into weedy cover." That's exactly what I see in our field, except that here their dense cover is a blackberry thicket, from which they seldom stray very far.

Savannah Sparrows occur from the Atlantic to the Pacific. With such a huge distribution you might expect the species to be fracturing into subspecies that eventually may evolve into full-fledged species. There are indeed several recognized subspecies of Savannah Sparrow -- 17 of them! This seems to be a very "plastic," dynamic and successful species. The incredible rate at which we are converting our forests and grasslands into weedy fields may benefit this often-overlooked "little brown thingy."

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THREE THOUGHTS ABOUT BEECH TREES
Wandering through bottomland woods along Sandy Creek I came upon a striking view. On that overcast day the oak-pine forest presented a dark, gloomy impression. However, all through the forest an understory of young beech trees about 10 feet high (3 m) positively glowed with bright, bleached-tan leaves. Seeing this, my mind drifted in at least three directions.

First, I just had to stand and admire those beech trees. In the books they're known as American Beech, FAGUS GRANDIFOLIA, and they grow into noble-looking beings 60-100 feet tall (18-30 m). They're among the easiest trees in our forest to identify because their blue-gray bark is so smooth that in some places it's hard to find a tree on which no one has carved his or her initials. The bark looks like elephant hide. Also, a beech's simple leaves are provided with distinctive saw-toothed margins, and the tree's buds are exceptionally long and slender. You can see a picture emphasizing the species' leafshape and bark at http://plants.usda.gov/cgi_bin/plant_profile.cgi?symbol=FAGR

A map showing beech's eastern North America distribution is at www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/fagus/grandifolia.htm

A second story coming to mind that day dealt with the beech's leaves. During the summer, beech leaves are dark green and glossy but, now, instead of being brown like most fall leaves, they are a bleached tan color that almost looked white in that day's somber surroundings. Moreover, the leaves' texture was like that of thin tissue paper. That's because beech trees hold their leaves far longer than most other deciduous trees, during the process reabsorbing nutrients from them. Most deciduous trees lose significant amounts of nutrients in their discarded leaves, which enriches the soil beneath the tree. In a sense, then, beeches don't share their leaf-riches with the rest of the community to the same extent as most other trees. Of course, they more than make up for their parsimony by providing crops of beechnuts, which are very valuable to wildlife. In fact, beechnuts were so important to humans in ancient times that the word "mast," from the old Anglo-Saxon mæst, refers specifically to beechnuts, though the term also can be applied to bunches of nuts in general.

A third story lay in the fact that in the forest before me the understory was nearly pure beech, though beech was practically absent among the mature trees. In other words, the oak-pine forest was in the process of being replaced by a beech forest. I would guess that originally the forest at that location had been beech forest but then, upon being clearcut, oaks and pines were the first to establish themselves. According to my old silvics book, "Beech seedlings develop better under a moderate canopy or in protected small openings than they do on larger open areas where the surface soil may dry out below the depth of the shallow roots." Whatever the deal is, that day I wished the young beech well, for oldgrowth stands of beech are always majestic and mysterious, seeming cathedral-like to me. It'll be a while before a beech forest reestablishes itself, however. One study of beech seedlings crowded together in the understory of a Pennsylvania forest found them needing 25 years to grow seven feet high.

So, beech are slow growing, sort of stingy with some of their resources, but when they finally reach maturity they bestow onto the landscape a sense of majesty, and their mast is of enormous value to a wide variety of wildlife. I like this species a lot -- the way it is reserved and non-participatory in some ways, but uncommonly generous to the community in others. Except for how the saplings crowd together, I wouldn't mind being a beech. However, since they do, I suppose I'll stick to aspiring to be a sycamore.

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SCOURING RUSHES ALONG SANDY CREEK
Not far from the beech, along Sandy Creek's muddy banks, nowadays the Scouring Rushes, EQUISETUM HYEMALE, are particularly conspicuous. Scouring Rushes are sometimes called Horsetails, and they're members of the Horsetail Family. They form dense, yard-high thickets year round but, now that the creek's banks are so brown, their dark greenness really stands out. These plants essentially consist of unbranched, pointy-toped cylinders growing very close to one another. You can see such a community at http://nasa.utep.edu/chih/plantimage1/equisetum20may02a.jpg and there are several close-up pictures at www.esb.utexas.edu/mbierner/bio406d/images/pics/equ/equisetum_hyemale.htm

Growing up in Kentucky coal country, often as I picked through debris around coal mines I found fossils of the long-extinct plant called Calamites. These were usually about arm thick and consisted of vertically ribbed, regularly jointed stems, with each joint bearing a whorl of slender, simple leaves -- just like our Scouring Rushes, but much, much larger. Calamites grew to 30 feet or more (9 m). It was an ancestor to our present-day Scouring Rushes.

Both the coal and the Calamites fossils around my home were Pennsylvanian in age -- 290 to 323 million years old. Flowering plants didn't appear until the Cretaceous, 65 to 144 million years ago. Therefore, having arisen at a time during evolutionary history when having flowers wasn't an option, Scouring Rushes reproduce by microscopic spores. Among the photos at the last-mentioned link are pictures of the plant's conelike "strobilus" at the top of the stem. That's where spores are produced.

When Scouring Rush spores germinate, they form a tiny, green, thumnail-like item called a prothallus, which lives independently for several weeks. Male and female sex organs appear atop the prothallus, sperm swim through water to the female part, and then a regular Scouring Rush stem grows from the fertilized female part. The mature Scouring Rush then produces more spores, and the cycle starts over. In other words, during the Scouring Rush's lifecycle there's an alternation between the tiny prothallus form, and the part we think of as the Scouring Rush. It's as if during the human lifecycle the female human were to give birth to a jellyfish. Then the jellyfish would do the sex business and the jellyfish's female part would give birth to a human, and eventually this human, without ever having sex, would give birth to another jellyfish, starting the cycle over. It's weird business but not uncommon. All of our ferns do something very similar.

If you scrape your fingernail along a Scouring Rush's stem, it'll feel like fine sandpaper. That's because ground-glass-like silica bodies reside inside the stem. Our ancestors scoured their utensils with Scouring Rush stems. In traditional Mexican markets you can still buy neatly wrapped bundles of Scouring Rush stems exactly for that purpose.

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"JELLY EAR" FUNGUS
Back before we became sensitive about what we called things, my mushroom books identified a certain kind of fungus currently very common on decaying sticks in the woods as "Jew's Ear" -- though it was hard to see any Jewish attributes about the fungus at all. One book now calls the same thing "Wood Ear" and another calls it "Jelly Ear," so I'll choose the latter name, just because it's the funniest. It's AURICULARIA AURICULA, and you can see one at the top, left of my "Jelly Fungus" page at www.backyardnature.net/f/jellyfun.htm

"Jelly Ears" are edible, but they're so tasteless that I can't imagine anyone taking much pleasure in eating them. I've read that in the old days sugar was sprinkled on them, they were set in the sun to dry, and the result was a sort of rubbery candy.

*****

WARM TOWNS, COLD COUNTRYSIDE
This week I made a brief run into Natchez and was astonished by how far advanced into spring the flora there was over here. Narcissuses were in flower and patches of lush, green clover grew over ankle high. Here my Narcissuses are far from flowering and the clover patches, while green, sure aren't lush.

Everyone knows that urban areas are warmer than the countryside because pavement and buildings absorb heat during the day and reradiate it at night. Friday morning, Jerry in central Mississippi wrote me that "Temperature this morning in Pelahatchie was 29F, 30 minutes later in Jackson it was 36F, shows the variation of rural and city."

So, the question is whether these drastic differences between our location along Sandy Creek, and Natchez 12 miles to the west, is merely "rural vs. city" or whether something else also is involved.

During the 12-mile return trip from Natchez I watched closely as each mile returned us to a colder season. Three to five miles east of Natchez the advanced spring still showed itself, long after the town's pavement and buildings had been replaced by oak-pine woods. This leads me to think that more is at play here than rural vs. city. I think the Mississippi River may contribute an enormous moderating effect on local phenology.

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ICE NEEDLES & SPATIAL DENDRITES
Most mornings this week a thin crust of ice formed in the old bathtub next to the barn where in summer I like to sit and cool off. Sometimes the ice crust was smooth and featureless but other times it was beautifully ornamented with long, intersecting ice- needles, or feathery designs known as spatial dendrites.

Since ice is just crystalline water (technically it's a mineral), and the shapes of crystals reflect the geometric arrangement of molecules, it seems that ice should have a fixed, regular form. Crystals of salt are cubical and quartz crystals are hexagonal, so why does ice assume so many configurations?

The answer lies in the fact that water molecules have a peculiar problem lining up with one another.

Atoms in most crystals align with one another rather neatly. In cubical grains of salt, the molecules squarely line up 90° relative to one another. In ice, water molecules align themselves according to a special force called "hydrogen bonding." The bond angle between an oxygen atom's hydrogen bond and the hydrogen in the molecule to which it is bonded is 109.47°. And that is NOT a convenient angle with which to construct simple geometric figures. Well, it's all a bit complex and I don't understand it so well myself. You can read a detailed, semi-technical account of ice in all of its forms at www.du.edu/~jcalvert/phys/ice.htm

You can see stick diagrams explaining hydrogen bonds and the molecular configuration of ice at http://stezlab1.unl.edu/Chem-191H-2002/Tony/Website/Page2.htm

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COMFORTING VISIONS OF VULTURES & MAGGOTS
A friend and I have been exchanging notions on what we want done with our bodies when we die. She's all for cremation, because she likes the idea of recycling her body's nutrients into her garden.

I regard cremation as acceptable, but not preferable. My problem with cremation is that the petrochemical- powered burning process doesn't benefit a rainbow of natural decomposers. I prefer for critters and microorganisms to benefit as they convert my fat to simple compounds of carbon, oxygen and hydrogen, my protein to simple nitrogenous compounds, and the calcium phosphate of my bones to ions of calcium and phosphate in solution.

My preferred first step for this process is for my body upon death to be devoured by vultures, chambered by maggots, and to have my bones gnawed on by any animal disposed to gnaw them.

I did not come lightly to this viewpoint. My middle- class, rural Kentuckian beginnings set me into the world with all the usual, culturally appropriate belief systems and sensibilities. Every reevaluation I ever made of my culturally bestowed predispositions was a painful process. I suppose that nothing would taste so good to me right now as a fried baloney sandwich with white bread and lots of mayonnaise. However, on mostly ethical grounds, I banished that pleasure from my life over 35 years ago.

It seems nearly always to be the case that every significant circumstance is compounded of features arrayed in opposition. This often means that there's a narrow and forbidding gate to paradise. In the present instance, the consoling vision of my remains diffusing back into the mother ecosystem must be attended by the knowledge that the appetites of vultures and maggots will comprise the vehicle of my release.

I accept this as a condition and, in fact, insist on it -- as one final gesture of generosity toward the mother ecosystem, and as one last ceremony confirming my confidence in the boundless magnanimity of the Creator of that ecosystem.