November 12, 2017

RAINY SEASON ENDS ABRUPTLY
This year the rainy season at the rancho ended around 4PM on October 24th. It had begun with a 27mm rain (1inch) on May, 13th. Both the season's beginning and end were amazingly abrupt, and complete -- nothing but a few light drizzles for months before it began, and now not even a light drizzle since it ended on October 24th. Last year there was something similar, but I can't prove it, since last year I didn't keep records. This year I did, day-by-day, except for the two weeks when I was traveling, and then my Maya friend Gener kept notes. You can see a chart showing this rainy season's rain accumulation on a week-by-week basis, at https://www.backyardnature.net/n/17/171112.gif

That chart is surprising. Some years ago I charted rainfall for Mérida, the Yucatan's capital city, and posted it at https://www.backyardnature.net/yucatan/wx-merid.gif

The Mérida chart shows at least a little rainfall throughout the year, with the rainy season beginning in May and lingering somewhat into December. June through October rainfall accumulation followed a more-or-less bell curve distribution, reaching a peak in September. Our rancho chart shows no hint of a bell curve distribution -- if anything, a barbell-curve distribution. The rainiest month appears to have been in June, when normally the season is just getting underway.

The rainy season's abrupt end isn't limited to our area. My gardening friend in Morelos state, in the highlands just south of Mexico City, reports that there the rains stopped so suddenly there that by the time he'd realized the dry season had arrived he'd lost important plants because he just wasn't thinking "dry season" and didn't water them as he should.

Our rainiest week of the season was the one beginning June 4th, with 117mm (4.6 inches) .The second wettest week, beginning October 15th, produced 110mm (4.3 inches). The whole rainy season accounted for 1087mm (42.8 inches). If the upcoming dry season is like last year's, probably until May, 2018 we won't see more than 20mm or so of rain (less than an inch), coming in occasional brief showers and drizzels as cold fronts from the north move through, so our year's rainfall will probably little more, if any, than the 1087mm documented here.

However, patterns are more and more unpredictable, so who knows what we'll really end up with?

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TICK TREFOIL BESIDE THE PIT
Every organism, even the most noxious weed, sometime during its life history has its moment of beauty, and that's the case with a certain herbaceous plant that volunteered to grow at the very rim of the deep pit beside the hut. In a morning shaft of sunlight its stately form is reminiscent of a little pagoda, as you can see at https://www.backyardnature.net/n/17/171112dm.jpg

With compound leaves consisting of three broad leaflets -- trifoliate leaves -- looking like leaves of garden bean vines, we can assume that this is a member of the Bean Family, the Fabaceae. A better look at the leaves is at https://www.backyardnature.net/n/17/171112dn.jpg

This is a vigorous herb, one with its stems and petioles thickly mantled with long, stiff hairs. Also, at the base of each leaf's petiole unusually large, well formed stipules flare from around the stems, reminiscent of garden peas. This is shown at https://www.backyardnature.net/n/17/171112do.jpg

If you're still unconvinced that we have a member of the Bean Family, look at the blossoms' classic "papilionaceous" shape -- bilaterally symmetrical, with an enlarged top petal forming a "banner," two side petals called "wings," and two lower petals fused to form a scoop-like "keel" -- at https://www.backyardnature.net/n/17/171112dq.jpg

A side view of a flower's corolla perkily nodding atop its long, hairy pedicel is shown at https://www.backyardnature.net/n/17/171112dp.jpg

So, it's some kind of Bean Family member, a kind of "leguminous" plant, so it ought to produce legumes. On older plants such as the twelve-ft-tall one (3.7m) in the garden, legumes are being formed, such as the one shown at https://www.backyardnature.net/n/17/171112dr.jpg

That's a special kind of legume called a loment. Loments are leguminous pods that when mature break into one-seeded joints. You can see that the loment is covered with stiff hairs. Up close it's seen that at least some of the hairs are hooked at their tips, shown at https://www.backyardnature.net/n/17/171112ds.jpg

So, the loment breaks into pods covered with hooked hairs that catch onto passing animals or trouser legs, carrying the pods into new territory.

These are all features of a particular Bean Family genus, the genus Desmodium. Species of Desmodium generally are called tick trefoils because of their trifoliate (trefoil) leaves, and the loment pods that stick to our clothing like ticks. In North America numerous Desmodium species present themselves as wildflowers and weeds.

The species in our pictures is DESMODIUM DISTORTUM, native of southern Mexico south through Central America to northern South America, plus it's invasive in much of the Old World tropics. The Yucatan Peninsula seems to be a little too arid for it, so it occurs here only spottily, and where it does occur it behaves like an invasive weed. In the area around the rancho it's fairly common, but I never saw it near Chichén Itzá.

Despite the stiff hairs that give the plant a rough feeling, the FAO suggests it as acceptable livestock forage and "green manure."

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MEXICAN CREEPING ZINNIA
During my mid-October visit with a gardening friend near Tepotzlán, Morelos, in the uplands just south of Mexico City, one of the most eye-catching plants wasn't one of the treasured ornamental plantings, but rather a small, mat-forming, daisy-like herb growing weedily in the mowed lawn and along the road. You can see the pretty effect offered by the blossoms in early morning sunlight when the leaves were still dewy wet, at https://www.backyardnature.net/n/17/171112sa.jpg

Two flowering heads are showed up close with my fingers in the background for scale at https://www.backyardnature.net/n/17/171112sb.jpg

Since the heads' blackish centers are composed of many tiny, cylindrical, crammed-together "disc flowers," and the orangish-yellow, petal-like structures are "ray flowers," we know that this is a member of the enormous Aster or Composite Family, the Asteraceae. That family embraces so many genera and species that usually it's a challenge to identify them to species level, so from the beginning we know to "do the botany." First, take a look at the leathery, scale-like "involucre bracts" forming a kind of bowl from which the disc and ray flowers arise, at https://www.backyardnature.net/n/17/171112sc.jpg

These involucre bracts are reminiscent of those of zinnia flowers, which also belong to the Composite Family. When identifying composites, it's wise to break apart a head to see how the disc flowers are arranged, and that's what has been done at https://www.backyardnature.net/n/17/171112sd.jpg

Important field marks to be noted there include the fact that each purple-topped disc flower is partly surrounded at its base by a scale, or bract. Also, the tops of each pale, achene-type fruit consists of a "pappus" of one or two teeth or sharp awns, instead of slender, white hairs such as those atop dandelion fruits, or some other configuration. Removing a ray flower from the head, we find the pappus atop the greenish fruit to consist of larger, purple awns, as shown at https://www.backyardnature.net/n/17/171112se.jpg

In that picture only one awn is seen. The slender, dark brown, curving item pointed at the picture's top, left corner is the dried-out style.

So, this attractive little plant in English often is known as the Mexican Creeping Zinnia. It doesn't belong to the genus Zinnia, but on the Composite Family's phylogenetic tree it occupys a very nearby branch, which explains those zinnia-like involucre bracts. Mexican Creeping Zinnia is SANVITALIA PROCUMBENS, native from Mexico south to Costa Rica. In the US sometimes it shows up as a weed but apparently it doesn't establish permanent populations. In Spanish it's acquired numerous evocative names such as Ojo de Gallo (Rooster Eye), Ojo de Loro (Parrot Eye), Hierba de Pollo (Chicken Herb), Hierba el Sapo (Toad Herb), and more.

In Mexico Mexican Creeping Zinnia traditionally has been considered a medicinal herb -- making "teas" by putting it in boiling water -- for dealing with stomach problems such as diarrhea, dysentery, indigestion, stomach ache, and vomiting. Other reported uses include for painful urination, inflamed gums, inflamed testicles, nervousness, and the "evil eye." Despite all these uses, to date no clinical tests have confirmed the plant's efficacy.

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BRAZILIAN DUTCHMAN'S PIPE
During my mid-October visit with a friend near Tepotzlán, Morelos, in the uplands just south of Mexico City, one of the most spectacular blossoming plants in my friend's garden was a woody, evergreen twining climber spectacularly covering a wall. One of many blossoms is shown at https://www.backyardnature.net/n/17/171112ar.jpg

At the right in that picture is an unopened flower. The yellow hole in the opened flower curves downward behind the flaring purple-and-white part forming a cylindrical tube, which then makes a U-turn upward. By tearing away one side of the tube and the corolla-like part, you get a better idea of the flower's structure, at https://www.backyardnature.net/n/17/171112as.jpg

You might recognize this as an amazingly large-flowered specimen of the group of vines known as Dutchman's pipes, or birthworts, genus Aristolochia, often grown in gardens, and with native species occurring in much of North America and the tropics. This giant-flowered species is ARISTOLOCHIA GRANDIFLORA, commonly called Brazilian Dutchman's Pipe or Giant Pelican Flower. It's a member of the Dutchman's Pipe or Birthwort Family, the Aristolochiaceae, native to Central and South America, but planted in the tropics and subtropics worldwide.

Instead of the flowers consisting of the usual calyx and corolla, they produce a corolla-like calyx, or perianth. The perianth's unusual U-shaped tubes helps the flower with its pollination. The blossom's strong fragrance entice insects, mostly flies, to enter the yellow opening, and descend the tube. In the above picture you can see that the tube constricts at its bottom, then opens into a larger chamber. This makes it harder for the pollinator to find the way out, so the pollinator spends a lot of time wandering around depositing pollen from previously visited blossoms, and gathering pollen to leave in the next flower visited. Making it even harder for the pollinator to leave, sharp hairs on the perianth's inner surface point downward, always encouraging the pollinator to continue toward the pollen, but discouraging attempts to leave. You can see downward-pointing hairs at the perianth's constriction at https://www.backyardnature.net/n/17/171112au.jpg

Aristolochia sexual parts also are somewhat unusual, in that the six stamens group around the style and are fused with it, forming the interesting structure shown at https://www.backyardnature.net/n/17/171112at.jpg

North America's native Dutchman's pipe species are known as important hosts for Pipevine Swallowtail butterfly larvae. The Brazilian Dutchman's Pipe is a threat to this butterfly. Pipevine Swallowtails lay their eggs on its foliage, the eggs hatch, and the tiny larvae crawl around eating the leaves voraciously, and then die after about three days because the leaves are toxic.

Often the name birthwort is applied to Aristolochia species. In fact, the genus name is derived from the Greek words aristos meaning "best," and locheia meaning childbirth. That's because some people see the flower structure of certain Aristolochia species as resembling a human fetus in the womb, and in the past the vines were used medicinally to treat pain and infections associated with childbirth.

The Dutchman's pipe name result from the flowers' shape resembling the meerschaum pipes once common in the Netherlands and northern Germany.

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IN SEARCH OF...
My friend Eric in Mérida sent us a poem that had been emailed to him from Wil, a friend up north, who'd come across the poem by accident. The poem, called "In Search Of," had been written by Dina G. McIntyre, an Indian-born follower of the Mazdayaznan religion and a Zarathustran (Zoroastrian) scholar, as well as a retired lawyer who has practiced before the US Supreme Court.

At first glance the poem turned me off because it began, "Beloved, I search for Your Face." It's just my makeup to get crusty around the use of such words as "beloved," and the mention of someone's face, but then I remembered that Eric doesn't send me schmaltz and happy-face-icon stuff. Also, I noticed that in the poem the words "Your Face" were capitalized. I myself capitalize the word "Nature" when I mean to show piety toward Nature as the physical-world manifestation of what others might call the Deity or God.

So, I gave the poem another chance, this time paying attention to the capitalization as the words' thoughts blossomed around me. The work still didn't appeal all that much to me, but something else about it did.

What I liked was how this poem was floating from person to person, along the way offering positive, friendly vibes. It'd been written by someone who felt moved spiritually, and then that special feeling had been shared with others. Wil up north found something worthy in the poem, and shared it with Eric, who liked it enough to share it with me, and now I'm passing it along to you.

This kind of sharing is especially important right now because nowadays a tidal wave of aggressive, bigotry-based negativity is washing across the world. To fight it, people like us need to be sending out all the ripples of nurturing, caring influences we can, for when enough ripples merge together, they become a tidal wave, too.

Here's Dina G. McIntyre's poem, a ripple that merged with Wil's ripple, which merged with Eric's ripple, which I'm rippling out to you, just in case you can deal with words like beloved and Thee:

*****

Best wishes to all Newsletter readers,

Jim

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