August 9, 2009
AN ECLIPSING WOOD DUCK
From up at the pond I heard a familiar, quick hoo-EEK! call, went to see, and sure enough a male Wood Duck, AIX SPONSA, paddled at the pond's edge, his long, slicked-back crest dangling behind his head. And what a curious-looking Wood Duck he was! He's at http://www.backyardnature.net/n/09/090809wd.jpg.
The young male was in his "eclipse plumage" -- a distinct plumage between the immature and adult plumages. Notice how the bird in the picture has the adult male Wood Duck's chestnut-colored chest but his flanks are white instead of the adult's tan. Though his crest is well developed, it lacks the adult's white strip through it, and the adult male lacks the wide, white eye-ring this duck has.
I hadn't realized that we have Wood Ducks out here but it turns out that the species is broken into two widely separated populations. The main body is in the eastern US and southern Canada and the other is mostly in the western tier of states, as shown on the map at http://www.mbr-pwrc.usgs.gov/bbs/htm03/ra2003_red/ra01440.htm.
At http://www.ncbi.nlm.nih.gov/pubmed/16156812 a research paper abstract addresses this curious distribution. Since mutations occur randomly at known rates along certain lengths of DNA strands, when a population breaks in two, the time of separation can be estimated by counting the number of mutations the two populations do NOT share. The more unshared mutations there are, the longer ago the populations separated. Knowing the approximate rate at which mutations occur naturally, a ballpark guess of the time of separation can be made.
The researchers, at the University of Maryland, report that the original Wood Duck population "most likely split about 34,000 years ago, and this time of divergence is consistent with the occupancy of multiple glacial refugia during the Late Wisconsin glaciation." In other words, the last ice age split the population and the separated groups haven't reunited yet.
Who'd have thought that a familiar hoo-EEK! one morning this week would end up thrusting my mind back into the last ice age?
There's a whole group of butterflies known as "the Whites," because they're mostly white, usually with only a little dark or dingy marking. The most commonly known white is the Cabbage White, introduced from Europe, often seen fluttering above garden cabbage plants. However, plenty of other much rarer and more interesting Whites can be looked for.
For instance, suddenly this week a White species has begun showing up here. One trapped in a spider web by the tips of both of his down-bent wings is shown at http://www.backyardnature.net/n/09/090809bu.jpg.
That tragic, pretty little creature is the Pine White, NEOPHASIA MENAPIA, fairly generally distributed in piney regions of western North America. Its caterpillars eat the needles of various conifers, especially pines, which is a little unusual for a White. Genetically the Pine White lies somewhat apart from other whites in our area because it's most closely related to tropical species who feed on mistletoes. There's conjecture that Pine Whites "got into pines" by having ancestors who fed on a mistletoe species parasitizing pine trees.
Pine Whites also "lek," which means that the males concentrate in a small area -- the upper regions of pine trees in this case -- in order to collectively display to females. Females tend to mate with the strongest, flashiest, sexiest, etc., in the group, with the consequence that usually only a handful of males pass on their genes.
Pine Whites also sometimes undergo snowstorm-like population explosions. On my hike this week I saw hundreds of them, but nothing like that.
The whole seasonal feeling here has changed. During the last week of July we had a week of hot weather, over 100° each day. Before that week, the world seemed abloom and springy, but now most things are fruiting, not flowering and, at least to me, it feels like fall. Suddenly the emphasis is on fruits, not flowers.
For instance, at about 4000 feet, small, head-high thickets of Bitter Cherry, PRUNUS EMARGINATA, are bearing clusters of little, reddening cherries, shown at http://www.backyardnature.net/n/09/090809pr.jpg.
The pea-sized cherries are too small and bitter for humans to eat, very astringent. If you've chewed on green cherry-tree stems, that's the taste, but stronger. Still, birds and small mammals eat them gladly. Also, the tree's slender, stiff stems provide preferred browse for Black-tailed Deer. The dense thickets the trees form by root-sprouting create important cover for many kinds of wildlife.
Bitter Cherry trees also benefited Native Americans. Fruits were used as laxatives and the roots and inner bark were boiled and ingested to prevent heart disease. The tree's bark peels off in long fibrous strips that can be used for making baskets and other implements.
This is a very important native species, occurring from British Columbia south to southern California, and east to Montana, Utah and New Mexico.
OREGON ASHES FRUITING
It's always a pleasure to meet for the first time a healthy, well established, dignified tree growing in its native land, photosynthesizing, flowering, fruiting, making shade, recycling nutrients, sheltering wildlife, just doing its thing, minding its business, contributing all it can to Life on Earth. Maybe there's something in my genes that causes me to be charmed by trees, and that's OK with me.
So the first time I came face to face with an Oregon Ash, FRAXINUS LATIFOLIA, one at a woods edge displaying its opposite, compound leaves as if in a museum, and graced with large, pale clumps of maturing fruits, I just had to stand back and admire, soaking in its presence. You can see such a Oregon Ash branch at http://www.backyardnature.net/n/09/090809oa.jpg.
A close-up of the fruits, sometimes known as "keys" but more technically called samaras (a winged fruit that doesn't split open at maturity), is at http://www.backyardnature.net/n/09/090809ob.jpg.
Oregon's forests are so heavily coniferous that only three broad-leafed, deciduous trees are listed as growing over 100 feet tall: The Golden Chinkapin, Black Poplar, and the Oregon Ash. Of these the Oregon Ash is the main general-forest tree, so out here Oregon Ashes are even more striking than they might be if growing in the East. Also, there's only one ash species here; six are listed in Weakley's Flora of the Carolinas.
Oregon Ashes occur in moist, fertile soils from western Washington through western Oregon into central California. Possibly because it's usually surrounded by outstandingly important timber producers such as Douglas-fir, its main use here is for burning, its wood being known for splitting easily and having a high heat value. Historically there's been local use of its wood for tool handles, sports equipment, boxes, barrels and furniture.
Golden Chinkapin, CHRYSOLEPIS CHRYSOPHYLLA, is another of Oregon's three broad-leafed, deciduous trees over 100 feet tall, and these days they also are flowering, though I find them only along ridges above about 4000 feet. You can see their really spiny female fruits at http://www.backyardnature.net/n/09/090809gc.jpg.
In the July 5th Newsletter Oregon's Tanoak trees, Lithocarpus densiflorus, were introduced. They are closely related to Golden Chinkapins and were described as evolutionary links between oaks and chestnuts. The Tanoak's nutty fruits, which look more like oak acorns than chestnuts, are shown http://www.backyardnature.net/n/w/tanoak.htm.
Golden Chinkapins also are evolutionary links between oaks and chestnuts, but you can see that their spiky fruits look more like chestnuts than acorns. At maturity the spiny husks, or "cupules," usually contain three, sweet, edible nuts that can be pretty hard to extricate from their spiny covers.
Older field guides place Golden Chinkapins in the genus Castanopsis, of which about 120 species are found in Asia. Recent genetic sequencing studies indicate, however, that the Golden Chinkapin became genetically isolated from its Asian homeland so long ago that it's evolved away from the original stock enough to be placed in its own genus, Chrysolepis. Only two Chrysolepis species are recognized and both are found in this area.
A POND OF "GRASS"
In the pond above my trailer about a month ago slender spikes of "grass" began poking above the water's surface. As stems and blades rapidly elongated mostly they tipped over and began floating, creating the water-clogged, "pond of grass" shown at http://www.backyardnature.net/n/09/090809jt.jpg.
Now the "grass" is issuing flower clusters, shown at http://www.backyardnature.net/n/09/090809ju.jpg.
A close-up of individual flowers is seen at http://www.backyardnature.net/n/09/090809jv.jpg.
In the last picture the white, fuzzy items at the top are three stigmas, fuzzy to catch pollen that germinates there and sends a pollen tube down through the slender style below the stigmas into the roundish ovary below. Inside the ovary, ovules fertilized by the pollen's male sex germ will mature into seeds, and the ovary will become a capsular fruit.
You can see from the flowers that this isn't a grass at all. Grass flowers don't have petal- and sepal-like appendages surrounding a spherical ovary like this. What we have here is a rush of the Rush Family, the Juncaceae. It's the Jointed Rush, JUNCUS ARTICULATUS. The best-known rush, or fellow member of the genus Juncus, is Path Rush, a wiry, foot-tall, tufted plant common along trails in woods and weedy places, and with flowers similar to those in the picture.
Jointed Rush is native not only to North America (but not most of the US Southeast and some central states) as well as to Europe, Asia and North Africa. In fact, it's such an adaptable, even aggressive plant that it's become a waterway-clogging aquatic weed in South Africa, Australia and New Zealand.
When I waded into the thigh-deep pond for pictures, one reason this species spreads so easily quickly became apparent. I used an opening through the cattails where deer and other animals enter the pond at night, leaving a trail through the rush-clogged water like an icebreaker trail through ice. As an animal wades across the pond, the rush's stems break and float to the surface and the stems' nodes often bear both roots and young sprouts, as you can see at http://www.backyardnature.net/n/09/090809jw.jpg.
In that picture the green, horizontal spike is the shoot -- technically known as a tiller -- and the tan, stringy things arising from the tiller's base and dangling downward are roots. Looking behind me where I'd waded I found several rooted tillers loose on the pond's surface. All they needed now was to reach mud, root, and join in the fun clogging the pond.
PORTULACA'S BOWL OF JEWEL-LIKE SEEDS
The world of fruits is huge, and fruits can be categorized in many ways. My overview of the fruit world is at http://www.backyardnature.net/fruits.htm.
One important structural feature used to differentiate fruits is that of whether the ripe fruit splits open or not -- whether it "dehisces." Ripe pea pods, okra pods and milkweed pods dehisce to release their seeds, but apples, bananas and squash don't. Of those fruits who do dehisce, the most common manner is to split lengthwise, like a pea pod splitting along its length. Alternately, some fruits develop holes, or pores, in their walls so that when the dry fruits are shaken atop their stems the seeds tumble out -- as with poppy pods.
The Portulacas, or Rose-Mosses, PORTULACA GRANDIFLORA, in Anita's rock garden, do none of that. Their manner of setting the seeds up for being knocked from the mature fruit is amazing. But, first, look at Anita's pretty serpentine-rock-garden Portulacas at http://www.backyardnature.net/n/09/090809po.jpg.
At http://www.backyardnature.net/n/09/090809pq.jpg the close-up shows a flower's bunch of stamens consisting of orange, pollen-releasing anthers atop slender, stiff, dark-purple filaments, with the several-parted style looking like a star-burst at the far right, each style arm ending in a fuzzy stigmatic zone where pollen grains are supposed to germinate. The style arms unite and lead down to the oval ovary hidden by the stamens.
Once ovules inside the ovary are fertilized by the male sex germs, the corolla dries up and shrivels as the ovary grows to approximately the size of a pea. When the shriveled corolla falls off, the ovary remains, now a mature fruit, and here's the thing I'm referring to that's amazing about it: It looks like a can opener has cut a slit around its circumference. Instead of splitting lengthwise like normal dehiscing fruits, this one splits around its middle. Take a look at http://www.backyardnature.net/n/09/090809pp.jpg.
The red "bowl" there is the bottom of the ovary. The white rim is scar tissue where the top half has come off. And the bowl is filled with shiny, finely ornamented, jewel-like, black seeds.
Pods that dehisce around their middles like this are said to be "circumscissile," and a more elegant way of offering up seeds to be scattered in a world of hard knocks can hardly be imagined.
BLOSSOM END ROT IN TOMATOES
A few of our tomatoes have on their bottom ends large, dark, scabby areas such as the yellow tomato shows at http://www.backyardnature.net/n/09/090809er.jpg.
That condition is known as blossom end rot and it's not caused by disease organisms, so it's not contagious and no fungicide or insecticide helps. It's caused by a number of environmental factors affecting the supply of water and calcium to fast-developing fruits. For example, if you hoe too close to the plant and break some roots, this may diminish the supply of water with calcium dissolved in it, resulting in end rot. Planting tomatoes too early in cold soil also can cause end rot, and so do periods of hot, dry weather with not enough watering.
I'm not sure why occasionally one of our tomatoes turns up with the problem. Our garden is watered with a sprinkler, so maybe the tomato plants are absorbing water through their leaves and that water may not contain the calcium that soil-water would.
OCCULTISM IN THE MOUNTAINS
On my hike this week, deep in the mountains on a road inaccessible by anything less maneuverable than a 4x4, I came upon a lonely open area where someone had spray-painted on the ground the symbol you can see at http://www.backyardnature.net/n/09/090809xx.jpg.
I assume that this is an occult symbol. Several times during my hikes this summer I've stumbled upon groups ranging from black-clad, target-shooting skinheads to folks looking like they might be doing something otherworldly. I suppose that I'm such a gawky old fellow that no one really cares when I stumble into their presence, so always people just ignore me. My impression is that gun-shooters, off-roaders and people holding meetings or ceremonies of some kind outnumber folks who enter the local national forest strictly for the natural environment.
History shows that during times of stress and uncertainty people become more religious, join cults, conduct séances, practice magic, etc. I understand why: When an individual wants more control of his or her life, it's easier to dance around a symbol on the ground or to pray for the intercession of angels than to confront problems at hand, and human minds are structured so that they can be convinced of almost anything.
Despite understanding, running into this symbol spray- painted deep in the forest cast me into a blue funk. For, I suspect that here was yet another example of someone going to an extreme seeking guidance or inspiration when guidance and inspiration already are freely available all around, in the forest, the sky, the Earth itself.
It was like seeing someone desperately looking for answers in a book, but instead of reading what's plainly written on the pages they open the book in random places, jot down the page numbers, and then use numerology to decipher "hidden messages" they imagine to be encrypted in the written-down numbers.
My lifelong experience with Nature suggests that the Creator of the Universe does not play around with hidden messages that way. The Creator writes Her will very plainly in the thing She has created, which is Nature. As music reflects the composer's mindset, Nature reveals the Creator's will.
If guidance in life is being sought, here are some of the most obvious of Nature's suggestions:
# Revere and protect diversity
# Use resources frugally, and recycle
# Keep evolving, struggling toward every higher states
# Know that some things can't be explained, and qualify as miracles; there's mystery in the Universe
This guidance is free and available to everyone. There's no need to dance around symbols spray-painted on the ground to have it revealed to you.
Best wishes to all Newsletter readers,
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