Issued from Rancho Regenesis
in the woods near Ek Balam Ruins north of Valladolid in
Yucatán, MÉXICO

December 31, 2017


This week I was flabbergasted when I finally identified one of our most homely looking but most commonly encountered weeds, one about knee high, and especially common along the weedy border of the garden. I'd been waiting for several years to try to name this plant, until I could see the flowers. But somehow until now all I've ever see have been the herb's clusters of wafer-like fruits. You can see such fruit clusters a little paler than the dark green, wrinkled leaves around them at http://www.backyardnature.net/n/17/171231dl.jpg

The leaves, arising opposite one another on the stems, suggest members of the Mint and Verbena Families, but those families don't produce wafer-like fruits. The fruits suggest something in the Buckwheat Family, but the leaves are all wrong for that. This week I gave up waiting for flowers and decided to try identifying the plant just by its fruits, so I drew a sprig of the plant close and began "doing the botany" with what's shown at http://www.backyardnature.net/n/17/171231dm.jpg

Now for the first time I noticed that some of the wafer-fruits bore tiny yellow things at their edges, one seen on a fruit in the picture's lower, left corner. With my poor vision I couldn't see what the yellow thing was, but I pushed my little camera's macro capabilities to the limit and got what's revealed at http://www.backyardnature.net/n/17/171231dn.jpg

When that image came onto the computer screen I was stunned, for I'd never seen or heard of anything like it. Apparently the two yellow items are unisexual flowers, the larger one on the left being the male, while the one on the right is the female. At first I was flummoxed, especially because certain features here were familiar, though never seen in such a bizarre configuration.

The male flower's yellow corolla seems to have something dark within it, toward its top. In the gigantic Composite or Sunflower/Aster Family, such dark splotches often show up in the same position in disc flowers in composite-flowers' centers. They're blackish anthers connected at their edges to form a tube around the style. And the female flower with its two pale, slender, outward-bending items more or less forming a V are styles with stigmatic surfaces -- just as with ray flowers like those of the Dandelion, in the Composite Family. The styles join with the top of the bulge below the two flowers, so that bulge is where the ovary or developing fruit is, and the thin wings surrounding the bulge are destined to help the mature fruit be dispersed by wind. If you need to review the Composite Family's commonly encountered but somewhat bizarre floral structure, take a look at http://www.backyardnature.net/fl_comps.htm

So, yes, this is a member of the Composite/Sunflower/Aster Family, the Asteraceae, but who would have thought a species could produce such tiny ray and disk flowers, and be satisfied with just one of each?

Once all this was understood, it was easy to identify this remarkable plain-Jane species is DELILIA BIFLORA, commonly found in waste places throughout tropical America, and becoming invasive in certain other tropical countries worldwide. For such a common plant, amazingly little is known about its life cycle and uses. It's just one of those plants that people ignore, waiting for it to do something flashy, when it's already done that, by being itself!


We've met several indigo plants, genus Indigofera of the Bean Family, certain species within the genus providing the famous indigo dye. Indigo species usually share certain features such as the blossoms' general shape, especially their prominent top petals, or "standards," their pinkish-red color, and the plants' stems and leaves bearing short, slender, somewhat stiff, close-lying hairs. You might enjoy comparing "variations on the indigo plant theme" among the species we've seen so far:

Our Coastal Indigo page is at http://www.backyardnature.net/n/h/indigo2.htm

Our Lindheimer's Indigo page is at http://www.backyardnature.net/n/h/indigo.htm

Our Guatemalan Indigo page is at http://www.backyardnature.net/mexnat/indigof.htm

Now notice these features as expressed by the plant found at the garden's weedy edge this week, at http://www.backyardnature.net/n/17/171231in.jpg

Its flowers up close are shown at http://www.backyardnature.net/n/17/171231io.jpg

A landing pollinator's view of the corolla's throat is seen at http://www.backyardnature.net/n/17/171231ip.jpg

It's pinnately compound leaf with five leaflets, the terminal one of which has a nice stalk, and with all the leaves with the right kind of low-lying or "appressed" hairs, is shown at http://www.backyardnature.net/n/17/171231iq.jpg

The indigo genus Indigofera is an especially large one, embracing over 750 species, including several species producing the indigo dye, and others that are medicinal. Our garden plant traditionally has been used medicinally to alleviate pain. It's INDIGOFERA TRITA ssp. SCABRA often known as Asian Indigo.

Asian Indigo is found throughout an extremely large part of the Earth's warmer parts, but its origin is uncertain. Probably it's from Eurasia, though it commonly occurs in much of tropical America and the West Indies. Being spread over such a large area, there's considerable geographic variation, and several subspecies are recognized. Most plants illustrated on the Internet bear leaves with only three leaflets, but the subspecies found in the Yucatan, ssp. scabra usually bears five.

The species typically is described as an herb, shrub or small tree. Our garden plant was about knee high, with a semi-woody base, and long, sprawling, slender, almost vine-like branches.


At http://www.backyardnature.net/yucatan/duckbill.htm we look at a common member of the Bignonia or Trumpet-Creeper Family that sometimes is called Pico de Pato, which means, "Duck Bill." That's because of the corollas' interesting shape. On that page our pictures of the pretty flowers were taken in September, so it's proper that now its fruits are to be found. And they are large, substantial looking fruits, as shown at http://www.backyardnature.net/n/17/171231am.jpg

That one hung all by itself about 15 feet up on the side of a tree trunk up which the woody vine, or liana, had twined.


At http://www.backyardnature.net/mexnat/hampea.htm we look at another woody plant flowering in September, the commonly occurring Hampea Tree, and nowadays it also is producing fruits, a cluster of which is shown at http://www.backyardnature.net/n/17/171231hb.jpg

Notice the neatness with which the capsules open into three parts, each cell bearing a seed. Most of the seeds in this group of opened fruits are blackened with what appears to be a fungus. Notice that the fruit closest to the image's right border has been been gnawed on and partially opened, possibly by a squirrel. The exposed seed in that fruit is blackened, so a good guess is that the other black seeds were contaminated with fungal growth through similar breaks in their fruit's husk, maybe by worms.


During my mid-October visit with a gardening friend in Morelos State, in the high-elevation volcanic belt just south of Mexico City, a certain vine caught my attention. It grew rampantly over my friend's brush piles, and regularly had to be pulled off ornamental evergreens, or they'd cover the trees completely, blocking off sunlight, and kill them. You can see one of the vines just beginning its attack on an ornamental at http://www.backyardnature.net/n/17/171231tc.jpg

With its viny habit and large, soft, hairy, deeply lobed leaves, it looked like a member of the Squash/Gourd/Cucumber Family, the Cucurbitaceae. The flowers' corollas were fleshy and yellowish, typical of the Cucumber Family, but their small size and arrangement at the tips of long peduncles was a bit unusual for that family. Even more peculiar were the flowers' bases, each blossom equipped with ten bulging glands forming a kind of knobby crown atop the dangling flowers, as shown at http://www.backyardnature.net/n/17/171231tf.jpg

A close-up of a male flower shows the typical cucurbitaeous feature of the stamens' filaments fused into a column, atop which the clustered anthers form a yellowish, globular mass, as shown at http://www.backyardnature.net/n/17/171231td.jpg

A frontal view into a male flower appears at http://www.backyardnature.net/n/17/171231te.jpg

Despite the vines having completely covered certain areas of unused land -- the vines can reach 6m long (20ft) -- I couldn't find female flowers. That's a shame if only because it's the female blossoms that produce fruits, and it's the fruits that this vine is known for.

The vine turned out to be very closely related to the famous Chayote vine, Sechium edule, which produces astonishing numbers of highly edible, easily grown, pale greenish squash such as those shown on our Chayote page at http://www.backyardnature.net/mexnat/chayote.htm

Our plant belongs to the same genus as Chayote. It's SECHIUM TACACO, in English usually called Tacaco. It's native to Costa Rica, but grown in Mexico for its fruit, and sometimes plants escape, as at my friend's place. My friend doesn't grow it, but he does buy ornamental plants from many sources, so possibly his "infestation" is from one of his purchased plants.

The Tacaco fruit, I read, are green, slightly spiny, and when fully ripe may still be very fibrous, and contain a seed that's too bitter to eat -- even hard as stone, according to one writer. However, immature fruits boiled in water are edible, with a flavor that some find reminiscent of artichoke. The fruits are ±pear-shaped, and average about 5cm long (2in) and half as broad.

In Costa Rica certain people are exceedingly fond of Tacaco fruits, but it seems that Mexicans generally think that if you can so easily grow and eat Chayote, why bother with Tacaco? Besides, as my friend's orchard shows, Tacaco vine can go wild in an aggravating way.


Part of the pleasantness of this season in the Yucatan is that in early morning everything is covered with dew. Most mornings are cloudless, so during the days' first hours herbage everywhere sparkles, each dewdrop a prism potentially turning ruby, silver, gold, jade, or amethyst, depending on the vagaries of breezes. The air itself smells utterly fresh, with mingling undertones of crushed herbage and moist earth, and breathing it in, the nostrils tense with chill. Snag a foot on a vine twining into an overhanging tree limb, and you get a friendly cold shower.

Another very agreeable feature of these first days after the Winter Solstice is that while orange-picking season is ending, tangerines are reaching their peak of lusciousness. What a pleasure seeing the fruits' perfectly ripe, grainy-green husks tinged with orange hanging among shadowy leaves, and to pick whichever fruit you want. With knowingly applied thumbs and fingers the husks almost pop off, but if you're clumsy then juice squirts out, but that's OK, because glistening streaks of sweet orangeness arcing through the morning air is something good to see. And then the tang of the tangerine's juice, both sweet and acid, and the absolute freedom to have another, and another...

Both morning dew and tangerines, then, are accompanied by specifically configured constellations of natural things, events, situations, and feelings and thoughts. So, what happens if on a certain dewy morning -- purposefully and with the intention of being like an artist blending colors to come up with something new, more complex, textured and nuanced than the two begining elements -- we enter the citrus orchard, pick and eat a dew-covered tangerine?

Here's what I'm getting at: With regard to finding joy and fulfillment in the world of reality, which is Nature, Nature Herself does most of the work by providing near-infinite pleasing things to experience, think about and have feelings for. Yet, we can know and feel even more exquisitely by consciously and systematically using our minds to have ideas on how to blend or at least juxtapose the things of Nature into ever more gratifying experiences.

For example, this essay is called "Dew Tangerine." But what if its title had been "Tangerine Dew?" Something in the English-speaking brain feels more comfortable with "Tangerine Dew than with "Dew Tangerine." "Tangerine Dew" implies a close relationship between a tangerine and its dew, but our minds don't know what to do with "Dew Tangerine," since it's hard to see how dew can be much affected by or have much to do with tangerines.

Naming the essay "Tangerine Dew" would have been the conservative approach, the title most comfortably easing into people's preexisting, tested and proven mental pathways. But, "Dew Tangerine" obliges the mind to search for obscure relationships and, finding none very obvious, to invent them, and experiment with new concepts involving dew and tangerines. I believe that by participating in such an artistic process, we ourselves grow in flexibility, perceptiveness and general magnanimity.

And I wonder: Isn't the spirit of "Dew Tangerine" as opposed to "Tangerine Dew" the same spirit with which the Universal Creative Impulse evolves forward the Universe itself, and its more interesting subsets such as Life on Earth? Begin with one thing, then fracture and evolve the ever increasing number of parts toward ever more gorgeous and meaningful diversity, interrelatedness of parts, and always with a general trend toward more profound feeling and awareness?


Best wishes to all Newsletter readers,


All previous Newsletters are archived at http://www.backyardnature.net/n/.