July 5, 2009
Everyone at least once in his or her life should have the fun of watching a wild bird's daily nesting routines. This week an American Robin, TURDUS MIGRATORIUS, has been incubating her eggs in a nest in an Oregon White Oak's forking branch about fifteen feet up and twenty feet from my door. She's sitting there as I type this, unmoving, her eye fixed on my door, the nest so well camouflaged that I wouldn't notice it if sometimes she didn't fly back and forth. As I look there now all I can see of her is her yellow, upward-tilted beak. You can see her, too, at http://www.backyardnature.net/n/09/090705rn.jpg.
Both the male and female built this nest. Though the female's head is slightly paler than the male's usually I couldn't make out which mate was doing what. Probably the following description penned a century ago, now online at the Birds by Bent Robin Page at http://www.birdsbybent.com/ch31-40/robin.html still is about right:
On every journey, practically, the female brought larger loads than the male, and twenty-two more of them. The actual shaping of the nest was done entirely by the female, the male usually dropping his load haphazard on the edge of the structure."
Robin nests usually hold four eggs, though the number can vary from three to seven. The incubation period ranges from 11 to 14 days
LEONA ON TRANS-GENUS BIRD COOPERATION
Commenting on my note last week about Violet-green Swallows having been seen defending and feeding a Western Bluebird nest, Leona in the Missouri Ozarks writes that one day "... I heard a Jay shrieking, and looked around to see a Jay batting the heck out of a cat's head, and the cat surrendering a Cardinal."
She further writes, "I wonder if birds who help birds of other bird families are responding to SOUND...a squeaky baby bird. Mother people in Wal-Mart's are known to start to go to a kid who says 'MAMMA' or even in my case 'GRAMMA'...it is just built into the brain, you cannastopit. If the female is lactating, THAT happens too."
TUMBLING FLOWER BEETLE
Deep in the mountains far from any paved road I came onto a large, thriving population of Yarrow -- the same white-flowered, ferny-leafed Eurasian invasive "weed" found along roadsides and in fields these days all across North America. Maybe a log-pulling mule a hundred years ago left poop there with a Yarrow seed in it, and this pretty colony results.
Atop one Yarrow's flat-topped, lacy cluster of composite blossoms I spotted a black beetle with a remarkable shape. You can see what I mean at http://www.backyardnature.net/n/09/090705tb.jpg.
Have you ever seen a beetle with such a pointy rear end, or such a curved back? Bea in Ontario identified it as a Tumbling Flower Beetle, genus MORDELLA. The common Mordella species is M. marginata, and this could be that, but I read that California is home to dozens of Mordella species, so who knows?
So, do tumbling beetles really tumble? What they do is to fall off their perches when disturbed, onto the leaves or ground below. It's more than a mere release of foothold, though. The hind legs are flattened and have an enlarged femur with which they can deliver a fair kick, which sometimes can result in a tumbling but more often just puts the beetle in a place other than where it was when it kicked. It's an escape mechanism not requiring too much thinking.
Bea Googled up the identity in just a few minutes and I asked how she did it. She replied, "I merely did a search in Google Images for: 'black beetle pointy abdomen' and I was lucky enough that it brought up one matching picture and I found out from that it was a Tumbling Flower Beetle, then I did a search for Tumbling Flower Beetle and so on... "
That's such a simple but powerful approach, using obvious keywords. Often when we use search engines we make it more difficult than it needs to be, groping for fancy concepts and terms, and end up not finding what we want.
SNAKEFLIES: "LIVING FOSSILS"
For the last couple of weeks a certain glisteny-winged critter has been flying about. When one flew into my trailer and began banging against the screen I finally got a good look at what it was. You can see it at http://www.backyardnature.net/n/09/090705sn.jpg.
Bea with her fast Internet connection had to tell me what that was, too. It's a Snakefly, genus AGULLA, unusual for its slender neck atop a slender thorax. Like dragonflies it bears two pairs of wings, thus four wings. The "stinger" at the rear end is actually the female's ovipositor used in the egg laying process. Snakeflies don't sting. They belong to the Neuroptera Order, which means that they're closely related to antlions, lacewings, dobsonflies and owlflies.
Something about these insects looks primitive, and there's something to that. Jurassic and Cretaceous rock strata turn up an incredible diversity of fossils of snakefly-like insects. However, 65 million years ago when a comet hit the Earth in the area of today's northwestern Yucatan Peninsula, not only did nearly all the dinosaurs consequently go extinct, but also most snakeflies.
Nowadays snakeflies occur throughout much of the Earth's Northern Hemisphere (they're Holarctic) except in northern and eastern North America. Being "relicts" from the distant past, nowadays most species are distributed over small areas, often restricted to a single mountain range.
SPOTTED CUCUMBER BEETLE
At http://www.backyardnature.net/n/09/090705cu.jpg you see an insect found in many gardens, the Spotted Cucumber Beetle, DIABROTICA UNDECIMPUNCTATA. This one was in our garden; the red background is provided by a nasturtium flower.
Though Spotted Cucumber Beetles look like green ladybugs the two beetle types shouldn't be confused. Ladybugs should be welcome guests, for they eat many of the creatures who eat garden plants. Spotted Cucumber Beetles have a much different reputation.
Adult cucumber beetles eat leaves of cucumber, squash, watermelon, and other vine crops, causing a special kind of damage known as "window-panning." Window- panning results when the beetle eats the lower surface and inside of a leaf, leaving the upper surface intact but causing it to turn brown. Typically so few cucumber beetles inhabit a garden that their chewing damage is negligible.
Much more dangerous to the garden is the beetle's ability to transmit bacterial wilt disease causing the early death of cucumbers and muskmelons. Just one beetle per plant can transmit the disease to a large portion of plants in a garden. Gardeners raising lots of vine crops but unwilling to use insecticides often plant Zucchini and Blue Hubbard squash to draw the beetles away from the real crops, since cucumber beetles are especially fond of Zucchini and Blue Hubbards.
In much of the country the damage done by Spotted Cucumber Beetle adults is nothing to be compared with that done by its larval stage, which is known as the Corn Rootworm, and which can severely damage corn crops.
FIELD CRESCENT BUTTERFLIES
In this spring's March 16th Newsletter I introduced you to a Pearl Crescent butterfly in Mississippi, on a levee next to a swamp. Its picture remains online at http://www.backyardnature.net/n/a/crescent.htm.
This week a close relative, the Field Crescent, PHYCIODES CAMPESTRIS, flitted around me during my mountain hiking and you might be interested in comparing the above picture with this week's relative at http://www.backyardnature.net/n/09/090705fc.jpg.
At first glance there's a lot of difference because the Pearl Crescent is much more orange than the Field. However, notice that the underlying pattern of markings is the same.
Field Crescents are regarded as the most common crescent butterfly in the western mountains. The Audubon guide says of them, "Males fly about the meadows looking for females, while females slowly flutter through the vegetation searching for asters upon which to lay eggs."
WESTERN TIGER SWALLOWTAIL
Speaking of common western butterflies, the Audubon guide says that the Western Tiger Swallowtail, PAPILIO RUTULUS, may be the most conspicuous of all butterflies in the West. You can see one near my place at http://www.backyardnature.net/n/09/090705ts.jpg.
That picture is about the same size and the butterfly is posed the same as in the picture taken this spring in Mississippi of an Eastern Tiger Swallowtail, so it's interesting to compare them. That picture is at http://www.backyardnature.net/n/a/swalltail.htm.
Placing one picture on one side of my computer screen and the other species on the other side, really I can't see any difference between them that I'd trust if trying to separate them in the field.
I know that what we have here is a Western Swallowtail only because that species occupies approximately the western third of the US while the Eastern species occurs in the rest. Some slight hybridizing is reported along the dividing line.
THE MADRONES' NEW LEAVES
This year Oregon's hot, dry season arrived late but finally we're regularly getting afternoon temperatures into the 90s. The air is so dry, however, that high temperatures here aren't nearly as daunting as much cooler temperatures with high humidity elsewhere.
My "summer feeling" is associated with high heat and humidity, and much lushness and greenness. Here the air's dry crispiness subverts that feeling. Our roadsides and forest floors even evoke "fall feelings" because they're littered with large, leathery Madrone leaves. Madrones are ubiquitous, small trees with distinctive smooth, red bark. Bearing green leaves throughout the year, Madrones have been dropping a few leaves ever since I arrived, but the rate of drop recently has increased dramatically. In late afternoon when hot, dry winds stir, sometimes there's even a little flurry of falling Madrone leaves.
Nowadays most Madrones bear both shiny, new green leaves, and older, yellowish ones, as you can see at http://www.backyardnature.net/n/09/090705mn.jpg.
Often when trees issue green leaves before dropping their old ones they actively recycle nutrients from the fading leaves into the new ones and I'm guessing that that's happening here.
THE SUGAR PINE'S LONG CONES
This week suddenly I've started noticing remarkably long, slender cones dangling from the tips of certain especially tall, slender pines, as shown at http://www.backyardnature.net/n/09/090705pi.jpg.
Those cones are on a Sugar Pine, PINUS LAMBERTIANA, found naturally only from Oregon through California into Mexico's northern Baja. Sugar Pines, reaching 200 feet tall (61 m), are the tallest of all American pines; their cones, up to 26 inches long (66 cm), are the longest cones of any American conifer. During my 2005 summer in California's Sierra Nevadas I photographed the tree's general shape along with two long cones. Those images are still online at http://www.backyardnature.net/sierras/pinesuga.htm.
Sugar Pines belong to the Soft Pine group, most species of which bear five needles per cluster, or bundle. The other pines I've introduced you to from here -- the Ponderosa, Jeffrey and Knobcone -- all are Hard Pines with three needles per bundle, except some Ponderosa bundles have only two.
Even more conspicuous than the Sugar Pines with their long cones are the abundant Tanoaks, LITHOCARPUS DENSIFLORUS, bearing chestnut-tree-like catkins of male flowers, and oak-tree-like acorns, as shown at http://www.backyardnature.net/n/09/090705tk.jpg.
A close-up of an immature Tanoak acorn is shown at http://www.backyardnature.net/n/09/090705tl.jpg.
You know that the overlapping scales on oak acorn cups are blunt and kept pressed close to the cup. The Tanoak's acorn-cup scales in stark contrast flair away from the cup and end in sharp points. Tanoaks are sort of an evolutionary bridge between oaks and chestnuts.
A hundred or more tanoak species are native to eastern and southeastern Asia, but there's only one species outside that evolutionary tanoak center, and that's ours. Recent genetic studies reveal that our Tanoak has been genetically isolated from the Asian species for so long and is so essentially different from the Asian species that probably it should be reassigned to its own genus.
Our Tanoak species is found only in Oregon and California. The field guide says that it grows up to 100 feet tall but what I see seldom higher than 20 feet. Sometimes knee-high Tanoaks bear male catkins and acorns as if they were adults. I'm assuming that these are Dwarf Tanoaks, Lithocarpus densiflorus var. echinoides, which intergrades with the larger variety.
The name tanoak reflects the former use of employing bark extract as a tanning agent. Tanoak acorns are bitter and need two years to mature. Squirrels eat them, and the bitter tannin in them can be leached out with running water. Some groups of indigenous Americans preferred Tanoak acorns because their high tannin content preserved the acorns better when stored for a long time.
Sadly, Tanoak is one of the species most seriously affected by Sudden Oak Death caused by the disease pathogen Phytophthora ramorum, which is not a fungus, not a bacterium and not a virus, but rather something else entirely. Sudden Oak Death disease isn't yet a problem in our local area but I suppose it's just a matter of time.
One of the most commonly encountered wildflowers blossoming these days is also one of the prettiest, the Elegant Brodiaea, BRODIAEA ELEGANS, shown at http://www.backyardnature.net/n/09/090705br.jpg.
Though Brodiaeas often are grown in gardens, they occur in the wild only in western North America. They're a whole different kind of wildflower not found naturally anyplace else on Earth. Brodiaea bulbs are an important food source for burrowing rodents. Native Americans ate the bulbs, which are reported as having a nutty flavor.
Our Elegant Brodiaeas turn up in serpentine barrens, rocky outcrops and even roadsides, especially where earlier in the year water might have pooled or flowed. At first glance the large, violet blossoms remind you of gentians. However, when you do the botany you soon realize that you have a Lily Family member here. You can see down into the distinctive-looking blossom at http://www.backyardnature.net/n/09/090705bs.jpg.
Six purple, petal-like "tepals" surround the sexual parts in the center. The pale structure in the blossom's center consists mostly of three male stamens pressing around the female part like three upraised hands. Each stamen is topped with two baglike anther locules, each of the six locules splitting lengthwise to release pollen. Between each of the three anthers a fuzzy stigma curves outward.
The most distinctive features of the blossom, though, are the three pale, tonguelike things with green bases between the purple tepals and pale sex parts. Those are staminodia, which are sterile structures derived from stamens. Most blossoms in the world of flowers don't have them, but some do; most but not all Brodiaeas have them. These are particularly large, conspicuous ones. I would guess that in this species the staminodia's service to the blossom is to force visiting pollinators against the sexual parts, assuring that pollen is left on the out-curving stigmas, and collected from the long anthers locules.
MY NEWEST SOLAR OVEN
Wednesday, July 1, was the official beginning of the fire-hazard season here, so I had to give up my morning campfires. In their place I've constructed my newest solar oven, which you can see in all its glory at http://www.backyardnature.net/n/09/090705so.jpg.
That's a solar funnel cooker, the detailed, illustrated, building instructions apearing at http://solarcooking.org/plans/funnel.htm.
The instructions call for a sheet of cardboard measuring 2 x 4 feet but I used a 3 x 6 sheet for more power. They advised gluing the aluminum foil in place but I stapled mine with a simple office stapler. Their design calls for painting a canning jar black and putting it inside a plastic bag, then cooking what's in the black jar. Anita provided me with a clear-glass pan and top large enough to enclose a small skillet with its handle removed, and I used that. The top of an old pot just happened to fit the skillet. The skillet and pan top both were blackened with soot from woodsmoke. You can see a view inside the cooker at http://www.backyardnature.net/n/09/090705sp.jpg.
The secret here is having the loosely sealed, black cooking container inside a loosely sealed, clear-glass one. Concentrated sunlight is absorbed by the black skillet and lid, they radiate heat, and the clear- glass enclosure keeps the heat from escaping, causing the heat to build to a very high temperature because of the greenhouse effect.
This was a pretty cheap creation and took only two hours to put together, yet it bakes my cornbread, fries eggs, simmers stews -- covers all the basics. A skillet-sized pone of cornbread or a really big biscuit made of whole-wheat flour takes about an hour to bake to perfection, and in an hour a couple of eggs get more than hard-fried. I'd worried that this far north such a design wouldn't function but so far it does as well as the manufactured kit I used in central Mexico a couple of years ago.
Each time I construct a solar cooker I'm reminded how we grossly underestimate the potentials of solar energy. The good part of that is that "going solar" will be much more productive than most of us think. The bad part is that as we screw up the Earth's weather with greenhouse-effect gasses and by releasing solar energy stored in fossil fuels over millions of years, the consequences can be much worse than we imagine.
THE NEXT REVOLUTION
Revolutions, Nature teaches, can lead to wonderful outcomes. One of the greatest revolutions in Earth's history took place when a group of extremist fish couldn't take it any longer and moved onto land, becoming the ancestors of amphibians and other future land-based animals. Other big revolutions include the one set afoot by the dinosaur-destroying Yucatan comet of 65 million years ago, and the arising of the mammalian brain, which enabled empathy and other complex emotions among its possessors.
Right now a revolution is igniting every bit as momentous as those earlier ones. As fish crawling onto land posed the question, "What'll happen when animals escape the limitations of the sea?" the revolution just now beginning asks this:
"What'll happen when humans escape the servitude imposed on them by their genetic heritage?" The background is the fact that humanity's genes were wonderfully fine-tuned for early primates on the African veld, but human cultural, intellectual and spiritual evolution has proceeded much faster than its biological evolution. Consequently, nowadays humanity's genetic programming continually sabotages further human advancement -- in fact threatens all Life on Earth.
The revolution beginning right now demands that self- destructive, Life-on-Earth-threatening values and manners of living dictated to us by our genes be replaced by values and manners of living based on rational thought. Our genes say eat high-calorie foods until sated, but rational thought counsels that we eat only what the body needs. Genes formulated to assure compulsive hunting and gathering among our ancestors now predispose us for gross materialism and overexploitation of resources, while rational thought reveals that for the sake of the biosphere humans must be content with a minimum of material goods. Our genes predispose us to follow the home-area's flag wherever it goes, but rational thought demands that no flag be followed carried by madmen, demagogues and the ignorant.
There's no flag for this current revolution. There's no leader, no Little Red Book or Bible, and no cigar at the end of the ride. There's only one individual at a time spread here and there across the surface of the planet asserting his or her personal will over negative, genetically based impulses arising from within. The revolution will succeed when enough of us, despite our natural urges, begin choosing healthy, psychically satisfying, sustainable living patterns.
Best wishes to all Newsletter subscribers,
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