October 30, 2016
On Tuesday, unexpectedly I got to use the Internet in Ek Balam. The first order of business was to figure out what species persimmon tree is shown at http://www.backyardnature.net/n/16/161030di.jpg
That's the branch of a tree about ten feet tall (3m) along the woodland trail through the forest to the Rancho. With the fruit's color, texture and size, what could it be but a persimmon? Breaking open the fruit, inside were several seeds just like a persimmon is supposed to have, and the custardy flesh tasted more or less like persimmon. The opened fruit is shown at http://www.backyardnature.net/n/16/161030dj.jpg
Seven persimmon species -- seven species of the genus Diospyros -- are listed for the Yucatan, so which is our roadside tree? On the Internet, no pictures of the fruits of several of the seven species could be found, and fruits shown didn't look like ours. However, the online Flora Mesoamericana provided a written key to species of the genus Diospyros, and with that and the list of species published for the Yucatan, with fair certainty our little tree seems to be DIOSPYROS YATESIANA, a species endemic just to the Yucatan, Guatemala and Honduras. It has no English name but with that binomial nobody should complain about calling it "Yates's Persimmon."
The Internet provides pictures of leaves and flowers for Yates's Persimmon, but not mature fruits on a living tree, so possibly our pictures will be appreciated by future researchers.
The main feature the ID is based on is the fact that on this tree several mature fruits cluster together, not just one or two in leaf axils, as with most persimmon species. The Flora Mesoamericana description of the species indicates that it's similar to the species Diospyros campechiana, which doesn't occur here, but which also bears clusters of several fruits. Also, the fruits on our tree are almost "sessile" -- without a fruit stem, unlike most other species. And, on the fruits of most persimmon species there's a conspicuous, much enlarged, semi-woody calyx subtending the fruit, but on this one there's no room for such a calyx. The calyx shows up as a blackish spot beneath the fruit.
During my unexpected session on the Internet, also I got to work on a seven-ft-tall grass species I've been wondering about. The grass's general appearance is just like that of the abundant African Guinea-Grass that normally dominates roadsides and weedy fields in this area, and it grows in the same habitats as Guinea-Grass. However, its diffuse flowering heads are very different. For comparison, first you can see Guinea-Grass's flowering heads at http://www.backyardnature.net/yucatan/guinea-g
The very different flowering heads of this other seven-ft-tall I'm talking about are shown at http://www.backyardnature.net/n/16/161030bb.jpg
This big grass is hairy. On its stem, you can see its stiff hairs often tipped with glands and arising from swollen bases, at http://www.backyardnature.net/n/16/161030bc.jpg
The flowering heads consist of spike-like divisions on which the individual spikelets, each containing a single floret, array themselves along just one side of the stem-like rachilla, as shown at http://www.backyardnature.net/n/16/161030be.jpg
Looking at the rachilla from below, you can see that the spikelets are aligned one above the other, and that they bear sparse but long, often gland-tipped hairs, at http://www.backyardnature.net/n/16/161030bd.jpg
The big, hairy grass has ligules consisting of a fringe of fine, short hairs forming a kind of collar where the blades make contact with the stem, as shown at http://www.backyardnature.net/n/16/161030bf.jpg
During my surprise afternoon with Internet access I needed four solid hours to figure out this grass's identity, and it sure was fun. At first I was almost certain that our grass was a member of the genus Paspalum, like the Paspalum langei we profiled at Chichén Itzá this August. You can review how similar that species was compared to our present one at http://www.backyardnature.net/mexnat/paspalum.htm
Several Paspalum species are listed for the Yucatan, but our unknown grass wasn't any of them. In fact, it turned out that our mystery grass is not listed at all by CICY, Yucatan's Center of Scientific Investigation, as existing in the Yucatan.
Our mystery plant is BRACHIARIA BRIZANTHA, in English variously known as Beard Grass, Palisade Grass, Palisade Signal Grass, and -- what seems most appropriate to me -- Insurgente Grass. Appropriate, because from what I can see this robust species from Africa is rapidly pushing aside Guinea-Grass, which itself is known as extremely vigorous and aggressive.
Genetically, Insurgente Grass is described as predominantly polyploid and apomictic. Polyploid species may arise abruptly when during meiosis chromosomes in a parent species don't separate as they were supposed to, resulting in a new species with twice, thrice, or some other multiple of the parents' chromosome number. Polyploids can't cross with their parents or other species with different chromosome number, may look quite different from them, thus constitute a spontaneously appearing, new species.
Apomictic species are those who produce normal looking seeds, but the seeds don't result from normal sexual fertilization; rather, genetically, they're clones of their mother plant.
How did this kinky African Insurgente Grass get to the Yucatan? It was intentionally introduced into the northern Yucatan on the grounds that it makes a superior forage plant for livestock, and is able to thrive on thin soils developed atop limestone in a tropical environment -- exactly like we have in the Yucatan.
In the immediate area around the rancho, Insurgente Grass is fairly common, appearing as small islands of plants within an ocean of Guinea-Grass. However, this week I got to travel the 80kms or so between here and Río Lagartos directly north of us and over the entire distance I saw abundant Guinea-Grass along the road and in pastures, but only four or five small populations of Insurgente Grass, mostly in the cattle-producing region just north of Tizimín. However, those small populations of Insurgente Grass were nearly purely Insurgente Grass, with little to no Guinea-Grass mingling with it.
When I see how aggressively Insurgente Grass is taking the place of Guinea-Grass, and noticing that Insurgente Grass produces much fewer wildlife-nurturing grains than Guinea-Grass, I wonder if introducing it here was a good idea.
The world is full of yangs and yins -- good and bad, male and female, hot and cold, pleasure and pain, strong and week, light and darkness, positive and negative, etc. Last week my bicycle offered a refresher course in the matter.
For, I've never known a bicycle with so many problems. By now only the seat and front tire rim have not been replaced or repaired. Last week I spent four mornings, and this week two, walking the three miles or so between the rancho and the small Maya village of Santa Rita, where the area's only good bike repairman lives. Normally I do my own repairs but here nobody has tools and parts but the experts.
The bicycle's yang/yin teaching arose with the tiring, time consuming, sweat producing nature of the walks. That was the yin. However, all that yin was balanced by the yang, which was the fact that the exercise I got between the rancho and Santa Rita made me feel great. I always forget how therapeutic and vitalizing walking is. I'm 69 years old now and though my vision and hearing are going, nowadays the body feels as good as when I was in my 40s. I'm a doddery old codger riding around in a race car.
But, maybe the most valuable part of the bicycle's yin/yang teaching was mental, not physical. In the mental domain, the yin manifested on the morning of my first walk to Santa Rita, carrying a bike tire on a stick over my shoulder like a hobo. Maybe because of a recent birthday, I got to wondering what my parents would have thought that crisp October morning in rural western Kentucky back in 1947 if they'd been able to see me now, an old man among Mexican weeds and cow poop, in soiled, sweaty clothes, tramping between two tiny Maya villages. And, what about all that schooling, all that resume building, the published works, the extensive traveling and networking... ?
But, during the course of those morning walks, yin gave way to yang as I penetrated ever deeper into the world of robust weeds along the trail sparkling with lingering morning dew, and smelled the moist earth and freshly macheted plants along the trail and plants very much alive emanating wholesome, sweet fragrances, and when I commiserated with an old farmer whose crop of beans was being eaten by rabbits, and when I happened to be the one in all that Chinese-painting landscape taking the time to pay attention to the blue sky 's clouds so gracefully expressing their meaningful moods.
Three of the six times I went to Santa Rita, the repairman wasn't home, though he'd promised me he'd be there. This repairman became my Zen guru revealing in his own way a certain nuance of the yin/yang thing.
That repairman who was there and not there, along with the bicycle which now I ride through forest, among fields and below the broad blue sky, said:
Best wishes to all Newsletter readers,
All previous Newsletters are archived at http://www.backyardnature.net/n/.