August 2, 2009
A CROWD OF BUSHTITS
Nowadays the dry season is beginning to bite. On Thursday the temperature in Grants Pass reached 109° F (42.7° C) and it hasn't rained for so long that the ground is cracking, meadows and unirrigated fields are turning dun-colored, and it feels and sounds crunchy when you walk in the woods. Returning from camping higher up last weekend I didn't see a single bird, other than one Raven solemnly winging across the valley at daybreak. I'm told birds move into the higher elevations at this time of year.
The previous late afternoon, though, up at my campsite on a ridge populated with madrones, just as the heat was easing a bit, a crowd of Bushtits, PSALTRIPARUS MINIMUS, had briefly moved past my tent and a couple of birds had paused to look at me. One is shown at http://www.backyardnature.net/n/09/090802bu.jpg.
"Crowd" doesn't sound right for a gathering of birds but it's the best one I can think of to describe a bunch of foraging Bushtits. Nearly always Bushtits are seen drifting across the landscape in hyperactive, profoundly social groups of a dozen or more birds, foraging for spiders and small insects. The word "flock" is inadequate for evoking their nervous energy. "Swarm" almost gets it but that word implies a larger number. "Mob" implies a threat but there's nothing threatening about these teeny, plain-looking little birds so easily identified by their very long tails and very short beaks. Even with such lengthy tails the birds reach only 3½-inches long (9 cm), so they're much smaller than a chickadee. As they fly about orbiting one another they softly, plaintively keep in touch calling a high, thin, fussing tsit-tsit-tsit...
Bushtits are the only North American member of their family, the Long-tailed Tit Family, or Aegithalidae, the other twelve members of the family being Eurasian. Our Bushtits are also the only species in their genus Psaltriparus.
Bushtits are found in open woodlands, scrubby areas and even suburban shrubbery, from Vancouver, British Columbia south through much of the western US to Guatemala.
TAILED COPPER ON A THIMBLEBERRY
Down in the valley where streamside Thimbleberries grow, the other day a butterfly showed up with rich, dark-rusty coloration different from anything else I've seen here. A little "tail" arose from his hind wings as if he were a hairstreak, but hairstreaks seldom are so foxy colored. You can see all this at http://www.backyardnature.net/n/09/090802co.jpg.
Another view, with sunlight exploding in his wings, is at http://www.backyardnature.net/n/09/090802cp.jpg.
Bea in Ontario with her fast Internet connection identifies this as a Tailed Copper, LYCAENA AROTA, called Tharsalea arota in my old Audubon field guide. Copper butterflies constitute a subfamily in the Gossamer-wing Family. Some copper species occur in the East but the West is home to most of them. Our Tailed Copper is distributed from here in southern Oregon south through California into Mexico, east to the Great Plains and New Mexico.
One reason I may have been missing this species is that it's most commonly found in moist areas, and I'm usually on dry slopes and ridges. Its main host plant -- what its caterpillars eat -- are wild currants and gooseberries of the genus Ribes, and you've seen that we have those here.
Tailed Coppers are "strongly sexual dimorphic," meaning that males and females are very different looking. The male's upper surface is copper-brown with an iridescent purple sheen (that's a male in the picture) while the female is orange with a dark brown pattern. Uncharacteristically for the coppers, male Tailed Coppers are territorial and in the morning perch in sunflecks, often high in trees, watching for females. That's what the one in the picture is doing.
A subspecies known as the Clouded Copper occurring near Los Angeles is classified as critically imperiled, but ours is the common type and is more or less holding its own, tending to be common locally, then absent from large areas.
Up at the pond one you see Water Striders skating across the water's surface, as shown at http://www.backyardnature.net/n/09/090802ws.jpg.
Basically you see water striders doing two things. You see them prowling across the water's surface looking for prey, traveling about five ft/second, or 1.5 m/second. If you flip a tiny bit of wood onto the water they'll jump on it with lightning speed. Second, you see them mating. One strider skates past the other and with the same quickness suddenly one mounts the other. It all happens so fast that you wonder how they can know what sex the other is.
Researchers have looked into that question. They placed little masks on male water striders so they couldn't see (!) and found that if they caused female water striders to issue computer-generated surface- wave and body-contact signals of about 90 waves per second, typical of males, the females were treated as males. Just think of the sensation of the water you're skating on feeling alternately masculine and feminine. An abstract of that research paper is available here.
Water striders stay atop the water because of the water's surface tension and because they have "hydrophobic legs" coated with wax. They paddle forward with the middle pair of their legs, using their fore- and hind legs as rudders.
I'm guessing that the individual in my picture is GERRIS REMIGIS because it looks like other images of that species, and that species is a very common one. However, in the Water Strider Family, the Gerridae, about 500 species are recognized in about 60 genera, so who knows whether it might be a look-alike relative?
EXFOLIATING MADRONE TRUNKS
A month ago our ubiquitous Pacific Madrones, ARBUTUS MENZIESII, were dropping crisp, leathery, yellow leaves, giving the forest floor a crunchy-dry, fallish feeling. Last weekend as I camped on a dry ridge mostly populated with madrones I witnessed something amazing. As a very dry wind approaching 100 degrees filtered among the trees, reddish-yellow flakes ranging from postage-stamp size to shreddings long as my arm showered from the madrones' trunks.
People talk about madrone trunks having three kinds of bark. One bark is "normal" -- dark, woody, scaly -- but in many places, especially on younger wood, this opens up to reveal a reddish bark beneath it, and then sometimes the reddish bark opens up show a pale green bark beneath it. The green bark isn't "inner bark," or the cambium layer. It's just a third layer of bark. You can see a trunk near my trailer showing all three at http://www.backyardnature.net/n/09/090802mn.jpg.
The confetti showering around my tent last weekend was the "middle bark" peeling off, the red one with curled, tan edges in the picture. When a stiff breeze came along it was like a heavy leaf-fall in autumn, except that some of the "leaves" were quite large.
On several trees with large patches of reddish bark exposed I was able to peel off thin, pliable, somewhat moist sheets a foot wide and two to three feet long. A square sheet pressed in a book dried to an admirable but somewhat brittle sheet of "paper" that could have been written on easily.
Why do madrones have three kinds of bark, with the reddish middle one exfoliating so spectacularly at this time of year? I can't find any informed answer. I'm going to make a wild guess, though:
This is happening exactly when it's so hot and dry here that I'll bet the trunks are actually shrinking in size. Maybe being able to shed bark from those large, newer growth areas is an adaptation enabling the trunk to shrink in these spots without the bark buckling. Buckled bark might provide entry points for insects and disease organisms.
If you cherish the days of high summer when you can take seldom-used paths through fields and along woods edges to gather blackberries, this week has been the very one when you'd do that in southwestern Oregon. What's more, blackberry picking here isn't nearly as daunting as in the US Southeast where usually I pick, for here there's no worry about chiggers, or redbugs, and even ticks are rare. The Southerner can hardly imagine such genteel blackberry picking as is normal here.
You can see a big cluster of berries near my trailer at http://www.backyardnature.net/n/09/090802bb.jpg.
In that picture I'm turning over a leaf so you can see an important fieldmark for this species -- the leaves' hairy-white undersurfaces. Another feature is seen at http://www.backyardnature.net/n/09/090802bc.jpg.
That shows how this species' main canes are "five-angled"; in cross-section they're roundly star-shaped.
The species shown, our most prolific wild-growing blackberry, is the Himalayan Blackberry, RUBUS ARMENIACUS (sometimes named Rubus discolor), an invasive species in North America originally from southwest Asia, but not the Himalayas. The species may have been first introduced into North America in 1885. Since its blackberries are larger, sweeter and more prolifically produced than with our native species, Himalayan Blackberries were often planted, and horticultural varieties have been developed from the species, the best known being Himalayan Giant and Theodore Reimers. In North America wild Himalayans occur mostly in the West but they're getting established here and there all across the continent.
Around here Himalayan Blackberries are absolutely abundant, forming dense, wildlife supporting thickets along nearly all roads with halfway moist soil that's not kept cleared. Native blackberry species do show up here and there and often their fruits are fine, though they tend to contain larger seeds and not be as large and sweet as those of the "Asian invader."
THE POND'S MARSH SPEEDWELLS
Up in the pond for a couple of months a little aquatic herb has been appearing here and there in shallow water along the banks, issuing one or two tiny flowers at a time. The plant projects the image of a retiring, reticent, frugal little being, but of course that's exactly the way it needs to be for it ecological niche. You can see the pagodalike plant arising from shallow water and bearing a single pink-striped flower at http://www.backyardnature.net/n/09/090802ve.jpg.
At http://www.backyardnature.net/n/09/090802vf.jpg you see the tiny, pretty blossom with its two stamens and with its lowest corolla lobe being smaller than the others. That may remind you of the flower of the Ivy-leafed Speedwell we looked at in Karen's yard when we passed through Mississippi in February. You can see that species' very different growth form but very similar flower structure at http://www.backyardnature.net/n/h/veronica.htm.
The two flowers are so similar because they're both speedwells -- both members of the genus Veronica. Our shy little Oregon aquatic is the Marsh Speedwell, VERONICA SCUTELLATA, and like the Ivy-leafed Speedwell we saw in Mississippi it's also an invasive from Europe. In North America it occurs coast-to-coast, spottily, mainly in northern wetlands.
Nowadays a yellow-flowered Composite Family member flowering along weedy roadsides is so similar to many other yellow-flower Composites that most people never give it a second look. You can see it at http://www.backyardnature.net/n/09/090802gw.jpg.
However, if you look closely at an immature flower head you'll see something very strange, as shown at http://www.backyardnature.net/n/09/090802gr.jpg.
At the left, the green, curled-back bracts, or phyllaries, forming the flower head's lower parts are pretty unusual because they are so slender and curled-back, but what's amazing is the copious, white latex filling the head's "cup." All the immature, green flower heads on any given plant of this species are absolutely gummy with this sticky latex. As the heads open and the yellow disk and ray flowers expand, the latex disappears, until finally the head looks "normal" like the head at the right -- though the curled-back phyllaries are still very striking.
This is one of 18 gumweed species listed for North America, GRINDELIA SQUARROSA. During my 2005 stay in California's Sierra Nevadas we ran into Grindelia hirsutula, which struck me as even gummier than this species. You can compare the current one with that one at http://www.backyardnature.net/sierras/gumweed.htm.
Back then my friend Fred told me how local folks there filled jars with gumweed heads and alcohol, and used the resulting lotion as a treatment for Poison Oak.
Sometimes I find small insects mired in the latex, dying. I can't find anyone explaining why the plant produces such large amounts of latex. Maybe it's just to keep insects from eating the flowers or laying eggs among them, or maybe there's no reason at all, it just happens.
There's research showing that species of Grindelia may make a good crop for planting in arid lands because their latex is chemically similar to "extractable diterpene resin acids" from which turpentine and other important chemicals are derived.
In the April 26 Newsletter I told you about the gray fruticose lichen Usnea, Old Man's Beard, pictures and story at http://www.backyardnature.net/n/x/usnea.htm.
At my trailer's elevation Usnea is the most conspicuous bushy lichen but as you go up in elevation into cooler, moister climes an intensely yellow lichen with the same bushy form appears. Atop higher ridges the yellow species is by far the most common. It's Wolf Moss, LETHARIA VULPINA, shown on a pine snag at http://www.backyardnature.net/n/09/090802wm.jpg.
Like many plants and fungi reproducing with wind-disseminated spores, Wolf Moss also occurs in the Old World. The story is that its name arises from the fact that Wolf Moss contains a toxic chemical, vulpinic acid. Ancient Europeans would mix Wolf Moss with ground glass and meat and leave it in the woods so wolves would eat it and die. Apparently the glass would puncture the gut making it easier for the vulpinic acid to do its dirty work. Northern California's Achomawi people poisoned their arrowheads with it but in dilute solutions other groups used it to wash external sores and wounds. The Okanagan-Colville people made a weak tea of it for treating internal problems and the Blackfoot used it for stomach disorders. Wolf Moss also could be boiled, either alone or with grape bark, to produce a bright yellow dye for decorating baskets.
This pretty, strange-looking organism must have been regarded as especially powerful and mysterious by those who once used it. I can just imagine shamans, herbalists and basket makers among the native people of these parts occasionally climbing into the upper elevations, maybe along the same trails I sometimes use, to gather it.
Some apple trees here are infected with apple scab disease, the symptoms on leaves and fruits shown at http://www.backyardnature.net/n/09/090802sc.jpg.
The "scabs" occur not only on apples and leaves but also on petioles, pedicels, and twigs. The disease organism responsible for this is a fungus, VENTURIA INAEQUALIS, and besides apples it infects pear, firethorn, and hawthorn. Here's how it works:
In spring when the temperature and humidity are just right -- about when tree buds are turning green before sprouting -- spores are released from infected leaves that have overwintered beneath the tree. The spores land on trees, germinate, and send rootlike hyphae into developing tissue.
As the hyphae mature they sprout asexual reproductive structures called conidia, which produce conidial spores. Conidial spores are unlike the spores we started with, so we're talking about two kinds of spores here, the first being special "ascospores" resulting from sex, the second being more like dusty fragments budding off vegetatively. We're seeing the asexual conidia-forming stage in picture. Notice that certain spots have gray fringes. That's where conidial spores are being produced.
The conidial spores cause secondary infections, causing the disease to get worse and worse through the summer. Eventually the apples may have much larger spots that crack open, and the apples themselves may be deformed. The tree's leaves may fall early, weakening the tree. You can see a mature infection at http://www.backyardnature.net/f/applscab.htm.
Venturia inaequalis overwinters mostly on fallen leaves, in immature fruiting bodies known as pseudothecia. This is where sexual reproduction takes place so that the following spring a new generation of ascospores can be released, starting the disease all over again. Scab lesions on woody parts may also overwinter, not undergoing sexual reproduction cycle. However, their production of conidial spores may continue the following spring.
Our first line of defense against apple scab is to plant resistant tree varieties, among which are Enterprise, Goldrush, Liberty, Jonafree, Macfree, Prima, Pristine, Redfree, and Sir Prize. The second most useful strategy is to rake up and burn all leaves below infected trees in the fall. After that, typical advice is to use copper- and/or sulfur-based fungicides per instructions. I personally don't like copper-based solutions, such as Bordeaux Mixture, because of copper's toxic effects as outlined at this link
HEAT'S LONG-WAVELENGTH THOUGHTS
On silent afternoons with no breezes, the temperature beyond 100°, sunlight heavy and glaring, there's a stunned, trancelike feeling. Some say they can't think when it's like this, but I believe we never stop thinking. It's just thinking of a different kind, less linear, more abstract, maybe on longer but more penetrating wavelengths. Here's a hot afternoon's long-wavelength thought from this week, inspired by watching nestlings fledge from their nests:
Like a nestling, a human baby is absolutely self- centered, focusing only on its own needs. Quickly the baby bonds with the mother and becomes part of a mother/baby unit. Further bonding with the father and siblings makes the baby's world more interesting and offers more life opportunities. This trend continues as years pass and the maturing child integrates into his or her community, then the nation.
This is a cumulative process, and at each stage of development the individual finds life more enriching. An enlarging perspective imparts ever higher levels of enlightenment with regard to what it means to be human on Earth.
Maybe most people end their growing-up process at the community or national level because maturing further takes effort. Also, conservative fellow members of the group often oppose further growth, seeing it as betraying family solidarity or as being unpatriotic.
But, with continued study of and experiences with "Life on Earth" one eventually bonds with the planetary biosphere, not just local subsets of it.
Moreover, I sense that beyond "Life on Earth," with successful meditation and flexibility of spirit, one can identify with the mystical creative impulse from which all experience arises in the first place.
The main trend in this growing-up process is that, step by step throughout life, the baby's intensely personal "me" grows ever more nebulous and less central while gradually the community, the "greater good," and finally the mystical Unity of things become ever more transfixing, ever more satisfying to identify with.
On these hot days when the body sits waiting for a cool breeze, moment by moment it seems as if there's less "me" hereabouts, that the landscape swims in heat of the pure, mystical Unity of things. Yet, what a thing that even in all this, there are little birds just leaving their nests with their "me-me-me" calls.
Best wishes to all Newsletter readers,