Skywatching

truck window

August, & the empty catbird nest catches small walnuts that will never hatch. An early autumn chill settles into my kneecaps. Last night, a cricket made entirely of electrons haunted a cross-continental audio connection between computers. It sped up & slowed down according to no change in temperature that anyone could discern. Thus, perhaps, the Great Motherboard amuses herself. Today at sunset the sky was full of chimney swifts, & I watched them for a while because it’s the height of the Pleiades, & this was likely the only skywatching I would do. Swifts are well named. The clouds turned orange above them while they weaved & wheeled. For whose chimney were they the wayward smoke? And in the morning, sometimes the sun finds a hole in the wall of trees opposite my porch & blinds me for half a minute before inching upward. Then wherever I look I see its negative: dark suns swimming in a cloudless blue.

El Arbol del Tule

Tule tree canopy

Tule tree limbs

Tule tree burl

My brother Mark, a professor of geography at Delta State University in Mississippi, recently returned from a two-week trip to the state of Oaxaca, Mexico, where he was surveying cycad populations with some Mexican colleagues. While there, he took the opportunity to visit the world-famous Arbol del Tule (pronounced too-lay), in the small town of Santa Maria del Tule. I prevailed upon him to share some of his photos of the Tule tree with Via Negativa readers. Please click on the images to see larger versions.

El Arbol del Tule

The tree is an ahuehuete (ah-way-way-tay), known in English as Montezuma cypress or Mexican cypress — Taxodium mucronatum. Genetic tests have shown that it is a single genetic individual, not the fused trunks of several trees as some had thought. Tule is a kind of reed; the town was built on the site of a former marsh. According to the Gymnosperm database,

“Ahuehuete” is a Nahuatl phrase that means “old man of the water,” a fit name for a tree that is always associated with swamps, streams or springs (Bautista 2005). The tree is sometimes also called Ciprés de los Panatanos (Cypress of the Marshes).

ahuehuetes in a stream

The ahuehuete is most often found growing directly in the current of streams and rivers in Mexico. It’s a close relative of baldcypress (Taxodium distichum), the most visible difference being the virtual absence of cypress knees. Like the baldcypress, the Mexican cypress is deciduous, dropping its needles in the dry season.

Santa Maria del Tule

Santa Maria del Tule is a small valley town a few miles east of Oaxaca City. It is easily accessible by local bus. The Arbol del Tule (l) dwarfs the church; a somewhat smaller ahuehuete (r) grows to the right of the church.

Tule tree foliage

Tule tree with tourists

Church at Santa Maria del Tule

The town square is dominated by formal gardens, which include some topiary. One gets the impression from these photos of a rage for order — a natural reaction, perhaps, to the otherwise overwhelming wild presence of the great tree. However, this species has been a literal building-block of civilization in Mexico for a very long time. The Aztecs and other Mexica peoples built cities on shallow lakes by first planting palisades of ahuehuetes, then filling the areas they enclosed with rocks and soil. Tenochtitlan itself was built in this manner, which means that one of the largest cities in the world — Mexico City — had arboreal grandparents, whose bones might still lie buried somewhere beneath it.

Tule tree plaque

Arbol del Tule
Common name: Ahuehuete or Sabino
Family: Taxodiaceae
Genus: Taxodium
Age: More than 2000 years
Girth (circumference): 58 meters
Height: 42 meters
Diameter: 14.05 meters
Volume: 816,829 cubic meters
Weight: 636.107 tons
Source: SEDAF
Town council 1996-98 [those who erected this plaque]

The age and even the exact size of the Tule tree are difficult to determine. The plaque at its base is unlikely to have the last word.

little tree at Tule

This is the smaller tree on the other side of the church, which would be considered remarkable anywhere else. As the aforelinked Gymnosperm database page puts it,

The Tule tree itself grows in a neighborhood that also holds six or seven other very large trees — one tends not to notice them, though, because most are behind walls and not publicly accessible, and because despite their large size (over 300 cm in diameter) they pale into insignificance beside the Tule tree itself.

Tule tree poem by Juan de Dios Peza

Regular readers know of my interest in public poetry. I was happy to see Mark’s photo of an official Tule tree poem, especially since the poem, by Juan de Dios Peza, takes a decidedly via negativistic approach. Here’s the text, along with my quick-and-dirty translation.

El Ahuehuete de Santa Maria del Tule

¡Con qué pompa a la vista
te presentas titan de estas
risueñas soledades!
Si sacuden tu copa las
tormentas sollozan en
las ramas las edades.
¿Qué te puedo decir?
Inspiras tanto que a mí
me basta recoger tu
nombre y darte mi mutismo
como canto ¡Junto a un
arbol así nada es
el nombre!

Juan de Dios Peza
5 June 1994

The Ahuehuete of Santa Maria del Tule

How grand and stately
the sight of you, colossus
of these inviting solitudes!
When storms rock
your crown, all the ages
moan in your branches.
What could I possibly say to you?
You inspire me so much,
I’d rather withdraw your name
and give you instead my silence
in the form of a song: Next to
a tree like this, a name
means nothing!

Juan de Dios Peza
5 June 1994

Mark Bonta prays to the Tule tree

Mark isn’t a terribly religious guy, but he said he found it strange that people would go into the church to worship with such a tree looming right outside. Here he is, as photographed by one of his colleagues, offering a prayer to the Arbol del Tule.

*

Be sure to check out the latest Festival of the Trees at Fox Haven Journal. The September 1 edition of the blog carnival will be hosted by the Spain-based blog Exploring the World of Trees; email links to Dan (treespecies AT gmail DOT com) by August 29.

Lines for a wet summer

gravel piles

A wet summer.
At the entrance to the hollow,
twin peaks of gravel.

*

Storm-carved ruts
on the gravel driveway
fill up with hailstones.

*

damselfly

Blue damselflies
patrol the slow-moving waters
of the blueberry bog.

*

Done berry picking,
I wash the bog mud off my legs
with brown bog water.

*

Morning thunder,
then rain. “It’s just getting it out
of its system, right?”

*

An indoor picnic.
The child climbs the steep stairs
to the green room.

*

shirt window

In lieu of a curtain,
a checkered shirt catches
the evening sun.

Palimpsest

turning the page

At last the author relinquishes his hold on the book he has been struggling to finish for almost a century. There’s a sound like the rapid turning of pages, or the beating of wings.

leaning tree

Two vultures were circling low above the treetops, as if in a slow-motion chase. I watched their shadows move through the forest, sliding up and down trunks and gliding over the shiny leaves of the laurel. On a cool morning, they were looking for light and warmth like everyone else. They were looking for a lift.

It’s not the vultures’ fault if their very name provokes fear and revulsion, simply because we are ashamed of where we came from. We too are scavengers with naked faces and an aesthetic preference for clean, straight bones. In the middle of the day, when the predators retreat to the shade, we venture out, alert to the crushed leaf, the snapped twig, the blood-dark berry. Stark contrasts are pleasing to us. The savanna — half grass, half trees — was our founding parchment, and we return to that garden every chance we get.

birth of a tree

At this very moment, in some back garden in Damascus, a brand-new tree is struggling to be born.

Buck in velvet

bolete pattern

At daybreak, the sound of hooves on gravel: a small buck accompanied at some distance by a doe meanders up the driveway, sampling the vegetation first on one side and then the other. As he rounds the bend opposite my front porch, I get a better look at the branches sprouting from his head, covered in dark-brown velvet — only four, rounded points so far, but the size and spread suggests he’ll be at least a six-point, and therefore a legal target come October.

Horns, many people call them, but the remarkable thing about antlers is that they are shed and regrow every year in a matter of months, unlike true horns, which are permanent. The energetic cost to the animal must be enormous. A rack, they call it, as if it were designed by God or evolution as a place to hang coats or display trophies. But this most prized of natural artifacts is itself a trophy — to hunters, and perhaps also to the deer, who holds his head so differently from a doe.

It’s just light enough to let me observe what he eats as he approaches the house:

  • the leaves of several goldenrod stalks, starting at the bottom and working toward the top;
  • a couple twigs of a multiflora rose bush, one of two beside the driveway that are as compactly rounded as if they’d been kept pruned by hedge-trimmers;
  • half of a large, compound leaf of a black walnut seedling the same age as the deer;
  • one stalk of wild garlic, starting with the tight fist of baby cloves at the top;
  • several mouthfuls of orchard grass;
  • the tip of a leaf of bracken fern;
  • some brome grass in front of the stone wall that borders my garden.

He’s near enough now that that I can hear the chewing and the smacking of lips. He crosses the road, lured by the sight of black raspberry leaves, and starts working on the end of the very cane that hosts a paper hornets’ nest at its base. A moment later, the anters jerk upright, and he bats at his shoulder with a hind leg. Then with one leap he clears the drainage ditch and lands among the cattails, twisting and rearing like a wild mustang with a bronco-buster on its back. A few seconds of that and he prances over to the woods’ edge, head still held high, to join what I imagine must be his sister — last year’s twins. If any hornets are still following him, he doesn’t show it, and neither does she. Their association is safe for at least a little longer from nature’s maddening sting.

Hat season

Mom in the berry patch

Ah, summer — time of berry picking, vine-ripened tomatoes, corn on the cob, and big ol’ floppy hats. Because it’s also high noon for deerflies, mosquitoes, no-see-ums, and, well, high noon. (There’s a video that goes along with this shot, by the way. Catch it at my mother’s blog.)

Dad in the woods

I’ll admit, though, I was a little shocked when my dad traded in his usual stylin’ John Deere cap for a shapeless straw hat he found in the closet. “The brim goes all the way around with this kind of hat,” he marveled. “The mosquitoes don’t come under it.”

I’m not entirely sure the hat was made for men, but whatever. My dad is nothing if not secure in his masculinity.

mushroom sombrero

It might be that Ma Nature is sending us subliminal messages, though. Between the Indian pipes and the mushrooms, hat-like things have been popping up all over the place. I watched gnats swarming around a rotting amanita yesterday: they crawled all over the top-side, but I didn’t see a single one venture beneath the brim.

Which got me to thinking there might be a big evolutionary advantage to this sort of behavior, because the underside of a mushroom, or any other projecting shelf, would be an ideal place for a spider to lurk. Maybe to the Diptera, it’s not that mushrooms are hats; hats are great big mushrooms.

Just, you know, a theory.

eggshell

When your hat is your home, you take it off at your peril. Things will never again seem as safe and dark and quiet as they did under a hat. Mosquitoes will come and sing in your ears, and not only because they’re looking for a blood meal. They get a darn good echo in there. Ears, being put on sideways, probably don’t look like hiding places for spiders in most cases.

But think of the way an ear is shaped. Maybe, just maybe, the mosquitoes too are looking for a hat.

Richweed


If you can’t see the slideshow, or if you’re on dial-up, go here.

I found the cicada struggling to mount a leaf, clawing feebly at the smooth surface. It had somehow survived the avian gauntlet, but death would come soon one way or another. Elsewhere in the patch, stray wings of less fortunate cicadas were scattered about, looking very much like transparent maple keys.

Few plants offer as many opportunites for arthropod watching when they aren’t in bloom as the large-leaved and aromatic Collinsonia canadensis. I’ve always referred to this plant simply as “horsebalm,” but apparently that name has been applied to other members of the Collinsonia genus as well, along with “stoneroot”; I should be calling it Canada horsebalm to be more specific, or better yet, richweed. Though prized by herbalists, and once an important medicine to the Iroquois and Cherokee, for us it’s mostly just a nice, citronella-scented plant that’s fun to point out to tour groups on hikes up the hollow — we always like to add an olofactory element to our tours. In another month or so it’ll send up spikes of yellow flowers, but why is it so popular with the six- and eight-legged crowd now? From what I could see, simply because its large, horizontal leaves help with thermoregulation: where they intersect with short-lived sunbeams in the otherwise cool forest, they’re great places to sunbathe.

Needless to say, this is a (semi-) macro photographer’s dream. Most of the woods is simply too dark to take photos without a tripod; I’m pretty much limited to snapping what’s in the sun. And since it was a cool morning, the insects were in no hurry to move on. But as usual, my attention was drawn as much to the stage set as to the actors: the shifting patterns of sun and shade, the color and texture of the leaves.

I wasn’t the only one drawn by the concentration of insect life. A funnel spider had set up shop, curling a leaf into a lemon-fresh lair of death. An assassin bug squash bug* seemed less interested in stalking prey than in feeding on a bird dropping. When I came in too close with the lens, it circled to the other side of its prize and assumed that pugilistic pose so typical of its kind. And a pair of harvestmen — or a harvestman and a harvestwoman, as the case may be — seemed most interested in each other. For the entire half-hour I was there, they stood face-to-face, barely moving except for their long front legs, which met and circled like foils in the world’s slowest fencing match.

I think I’ll be calling it richweed from now on.

*See comment by Rebecca Clayton below.

Flickr slideshow created following the very helpful instructions of Paul Stamatiou.

Paths of infection

trail

In a few more years, the path in this picture will be two centuries old. That’s fifty years older than any of the buildings in the hollow. They’re the healed remains of the roads the colliers built when they first clearcut the mountain, with results that must have been catastrophic for the hollow: floods, fire, massive loss of topsoil. But now, chances are if you come to visit in any other season than winter, our moss-covered trails are one of the things you’ll most remember about the place. They’re beautiful. In spring and summer, before the leaves fall and turn every step into a loud whisper, it’s possible to stalk through the forest as quietly as a burglar.

I always confuse the path with the destination. Don’t you? I start out intending to go somewhere, but then something catches my eye and I slow down for a closer look. Then I notice more. An hour hour later, I’ve only made it half a mile from the house.

laurel leaf

Nothing draws the attention quite like someone or something with a disfiguring disease. Whatever is decimating the mountain laurel here begins with colorful eyespots: brown rimmed with red and yellow, like targets in reverse. With certain kinds of sickness, yes — the leading edge of infection is marked by unnatural brightness. That fever glow.

rash

I found a black gum tree with a bad case of warts. Each wart is a hermit’s cell for an Eriophyid mite, a microscopic, two-legged relative of spiders. It goes through a mere two larval instars, and manages to have sex while maintaining its immaculate separation from others of its kind:

Mites do not mate with each other; sacs that the male leaves lying around on the leaf surface fertilize the female as she walks around.

Freedom from sexual contact can be liberating. Some species of Eriophyid mites alternate all-male generations with all-female generations. Very little is known about them beyond these basic facts. Some 90 percent of Eriophyidae have yet to be named and classified by taxonomists, so I suppose chances are good that this is one of them.

For the tree, the galls aren’t the sickness, they’re the treatment. The tree would say, with some justification, that each mite is walled in to keep it from spreading. But the mite, like thousands of other gall-making arthropods, is in fact practicing a kind of ju-jitsu, using the tree’s defenses against itself. The feeding chambers are not only ideal for solitary contemplation, if such be the bipedal mite’s inclination, but keep out most predators, as well.

After they attain adulthood, the Eriophyidae abandon their chambers. This is the time when accidental sex may occur. Many of them also take to the wind and float for miles, like the Daoist sages of legend. Some of them, no doubt, end up in my lungs.

bear tree

This black gum bears the scars of somewhat larger animals — bears and humans. When I painted a trail blaze on it seven years ago, I can’t remember seeing the other marks there, but judging from the depth of scar tissue, bears have been carving up this tree for some time. Though they much prefer electric and telephone poles to communicate their “Kilroy was here”-type messages to other bears, any conspicuous tree, living or dead, will do. For hikers, this is a useful reminder that they aren’t the only ones using the trails. For bears, it is perhaps a gratifying reminder of the fact that our paint marks are no match for their claw marks. Bears often destroy human-made things left in the woods — it’s as if they regard us as some kind of enemy.

For the tree, unless and until the trunk is completely girdled, none of this is a real impediment to continued growth and prosperity. Black gum trees are masters at walling off wounds with thick scar tissue. They almost all rot out at an early age, making them impossible to date by ring counts. But the outer shell of a mature black gum is hard as iron.

charred

White pines fight disease with tars, which can sometimes keep them standing after death for as long or longer than they stood as living trees. A century after the forest fire, a short-lived path that the flames took up the trunk of a pine tree is still marked with charcoal and a livid blaze.

A non-plague of non-locusts

egg-laying cicada

The locusts are, it must be said, a bit of a plague on the locusts. The males call “Pha-roah! Pha-roah!” in a slow southern drawl while the females plunge their scimitar-shaped ovipositors into the thorny twigs, sometimes so deep that they break. All along the top edge of the field, the black locusts are acquiring a pruned and chastened look, as if they were the victims of some very localized storm.

cicada damage

Of course, 17-year “locusts” are really cicadas (see Brood XIV). According to some sources, when early European settlers first encountered periodical cicadas in eastern North America, the only parallel they could think of for such an extreme insect outbreak was the plague of locusts in the Bible, so “locusts” they became — despite the fact that, as members of the order Homoptera, they could scarcely be more distantly related to true locusts, which are grasshoppers, Orthoptera. According to the Locust entry in the Wikipedia, however, the conflation goes much further back, to “the Vulgar Latin locusta, which was originally used to refer to various types of crustaceans and insects.” The English essayist Thomas Browne was bemoaning the confusion between locusts and old-world cicadas as early as the 17th century. And obviously the popular description of the call of Magicicada septendecim as “Pharoah” shows the unabated influence of Exodus 10:4-15.

However, it would be a great exaggeration to say of these “locusts” that “they covered the face of the whole earth, so that the land was darkened; and they did eat every herb of the land, and all the fruit of the trees which the hail had left: and there remained not any green thing in the trees, or in the herbs of the field, through all the land.” Here’s what the folks at Cicada Mania say:

Question: Will the cicadas kill my trees, shrubs and flowers?
Answer: Possibly. Cicadas don’t kill flowers and shouldn’t damage shrubs, but they can do damage to young, wimpy trees like ornamentals. If you have wimpy little trees, you can net them to keep the cicadas off. Tree species that aren’t native to North America won’t fare as well as native species. Trees that lose a lot of branches typically revive after a year or two, but they will be ugly in the mean time. Cicadas actually are a benefit to trees, as they destroy the weaker branches. Please don’t use pesticides — you’ll destroy the good bugs as well as the “nuisance” bugs, and ultimately do your garden and the environment a huge disfavor.

Of course, as larvae, cicadas do subsist on tree sap, but given that cicadas and deciduous trees have evolved together, I doubt that they do much to weaken the trees. Though the science is inconclusive, it’s likely that their extensive tunneling benefits the trees by aerating the soil, and possibly by creating macropores for new roots and fungal mycelia. An AP article quotes a Dr. Frank Hale from the University of Tennessee:

The holes from which they emerge aerate the soil around the tree roots, Hale said. The millions of decaying cicada bodies supply nitrogen and other nutrients, which rain washes down the holes to the tree roots.

However, a Penn State Ag School publication for orchardists assumes the worst, and considering the unique stresses on heavily pruned and sprayed trees in monocultural plantations, it may well be on-target with its recommendation to prevent egg-laying at all costs. It also emphasizes netting if feasible, and mentions the harmful effects of pesticides on beneficial insects.

cicada in scrub oak

Do the various Magicicada species vary in their arboreal preferences? I’ve mentioned black locusts as a favorite for swarming and egg-laying activity (see my video at the Plummer’s Hollow blog), but I suspect that’s largely because of their location in the field-forest ecotone. The cicadas here do show an affinity for forest edges and openings, regardless of where they originally emerged. I don’t know if the fact that locust trees are nitrogen-fixing legumes makes them any more attractive as adoptive mothers to cicada larvae. We have noticed relatively few cicadas in the black walnuts that surround the main house, which might seem logical given the toxicity of walnut roots to many other plants, but it seems that if we had the rarer third species, Magicicada septendecula, that might not be the case:

Within the same brood, the three species are always perfectly synchronized, but they are separated microspatially by having different habitats within the same woodland. Magicicada septendecula prefers ovipositing in hickories and walnuts, and emerges in higher proportions under those trees than under comparable oaks. Both M. septendecim [the “Pharoah” species] and M. septendecula occur together in upland woods, but septendecim exhibits much less host specificity than septendecula. The latter species is much rarer than septendecim; it can usually be heard chorusing in local patches within a woods occupied by septendecim. Magicicada cassini is a species of floodplain woods, and characteristically can be seen to replace septendecim and septendecula as one moves down a wooded slope leading to a stream. Over much of the eastern United States, however, the original forest has been extensively disturbed. Periodical cicadas survive and reproduce surprisingly well in cutover, scrubby second growth. Tree species characteristic of floodplains, like American elm, are often a component of upland second growth, and, especially in such situations, cassini, septendecim, and septendecula become intermixed though they remain reproductively isolated. The present lack of microspatial separation in many situations, then, is an artifact of human disturbance.
—Henry S. Dybas and Monte Lloyd, “The Habitats of 17-Year Periodical Cicadas (Homoptera: Cicadidae: Magicicada Spp.),” Ecological Monographs, Vol. 44, No. 3 (Summer, 1974)

That might explain why the M. cassini cicadas are so much louder and more numerous around Canoe Creek State Park, much of which is floodplain or early-succession second growth. At our annual Audubon Society picnic last week, they were nearly deafening. In fact, a friend just told me that the dog-day cicadas are usually very numerous there, too — and regardless of the species, they make excellent fish bait, he said. Hardly the stuff of plagues.
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Today is the deadline to submit links to the next Festival of the Trees. Details are here.

The shortest night

top-heading garlic

The morning after the summer solstice, which arrived just before 8:00 p.m. here, the garlic tops have each coiled another half-turn. Irises that were once blue dangle curled brown locks and raise flags of surrender, milky as a blind man’s eyes. It’s chilly. I grab my hooded sweatshirt off the doorknob and stand staring for a moment at my reflection in the bald brass.

cicada wings1

A 100-foot section of the mowed path leading from the garage into the woods is bejeweled with cicada wings, hundreds upon hundreds of them, covered with dew and glinting in the morning sun. What brought them there?

They had to have been brought: it’s not an area where either the emergence or the courtship of the 17-year cicadas have been particularly intense, or indeed noticeable. There are no overhanging branches from which birds might have discarded the wings as they ate — in fact, the wings peter out as soon as small trees begin to line the trail.

I suspect raccoons. What else could it be? I can picture them gathering there in the light of the just-past-full moon, squatting companionably as they pull the wings off their squirming victims and chew, chew, chew.