Although never common, bunches of Joint-tail Grass can be found
in south Texas along creeks and streams where livestock are not
grazing. Joint-tail Grass is related to teosinte, the precursor
of modern corn, and shares many of its attributes. This
specimen was found along Medio Creek in Bee County. Here you
see a close-up of the two-pronged seedstalk. It is a woody
spike with the seeds inside small cavities, one seed per joint.
These spikes break apart at the nodes as part of the normal
process of scattering the seeds. Robert Benson photo.
Identifying LBBs and Odd Grasses. As a
naturalist I feel that I am expected to know how
identify everything. But of course this is
impossible. The best a naturalist can do is to know a
little bit about everything in general. And hopefully,
each naturalist knows a lot about something. In other
words, we naturalists specialize in some aspect of
Some of us specialize in birds, others know botany well,
some focus on insects, and a crazy few specialize in
scat. This last one is not my specialty; all scat looks
like poop to me!
think my specialty is bird identification. I have spent
many years learning the birds and their field marks.
Even so I still cringe when someone asks me, “What is
that little brown bird?”
usual answer, “Er…hum. A sparrow?”
that might satisfy the incurious person, but most people
want to know what kind of sparrow. There are over 40
species of sparrows in North America. And they all come
in various shades of brown.
Identifying south Texas sparrows is hard. But once you
learn them, you’ll be proud of your ability. It’s best
to start with the easy ones like this Lark Sparrow. It
is common in the hedgerows and fields of the brush
country. It is the only sparrow with a showy harlequin
face pattern, an unstreaked breast, and a spot just
below its throat (the stickpin). When it flies, it
shows white spots on the corners of its tail. Robert
Sparrows are hard to identify. Birders tackle sparrow
identification last as they learn their birds. These
little brown birds (LBBs as I call them), take a lot of
practice. But it can be done. Look at the
bird-in-question’s breast and then its head. Look for
patterns and plainness. By this method you can usually
narrow down an LBB to a species. Good luck!
Grasses are even more difficult to identify than
sparrows. Grasses are green, and unless you find them
in flower or with seeds, they really all look alike to
the uninitiated. At least they do to me. But I am
working on learning grasses.
can ID johnsongrass (big with yellow mid-veins and an
open, reddish panicle) and inland seaoats (midsize,
grows in shade, and has a side-drooping panicle with
flat spikelets). Also, these two are pretty easy to
figure out using pictures.
It’s the vocabulary that gets me. I mean, what exactly
is a panicle, a spikelet, a lemma, or a glume?
I’ve learned that a panicle is a branching seedhead.
The individual seed with its wrappings is called the
spikelet. Glumes and lemmas are those wrappings (I
when I came upon a new grass in the bottomlands of our
South Texas creeks, I knew it wasn’t johnsongrass or
inland seaoats. No panicle. Instead there was a
two-pronged seedstalk (called a spike) sticking out of
the top of the grass.
spike was cylindrical, woody, and had nodes (joints)
about a half inch apart. When I touched the spike, it
broke apart at the nodes! I examined my handful of the
sections and realized each one had a groove leading to a
small hole on one side. Cutting one open I found a
single seed nestled in a hollow inside the section of
This grass was Joint-tail Grass (Coelorachis
cylindrica). I think it is pretty cool how its
seeds were protected inside the stalk. A wind or a
brush with an animal would break the little joints off.
A rain could carry them to a new location.
Joint-tail Grass is found in the southern states, but it
is not too common anywhere. I read that it is quite
palatable to livestock. If grazing animals find it
first, you’ll never see it. But the joint may protect
the seed while it passes through the digestive tract of
the animal. It can then be deposited, along with a bit
of manure to fertilize it, in a new home.
most fascinating thing about Joint-tail Grass is that it
is very similar to teosinte, a wild grass from
Mexico. Archeologists think it has been in cultivation
for over 10,000 years. Teosinte is believed to be the
ancestor of modern corn.
Wild-type teosinte seeds are enclosed in a hard case
formed from the seed stalk. Over 4,000 years ago,
Aztecs in central Mexico discovered a mutation in their
fields of teosinte. The seeds were only partially
covered by the hard case. The new teosinte kernels were
attached to the side of the stalk and were much easier
to extract for food.
They selected these and planted them instead of the
hard case variety. Thus they moved the evolution of
corn forward greatly. Modern geneticists have
discovered that a single gene was responsible for this
change. It seems that only five genes were involved in
the transformation of teosinte to modern corn. It is
very likely that each genetic change was selected for by
humans growing teosinte for food. Corn was, and is, a
staple in the human diet.
wonder the Aztecs called it teotl + cintli in the
Nahuatl language. “Teotl” means God, and “cintl” means
dried ears of maize. Did that translate as Corn of the
Gods? Or perhaps it meant the Corn was a God.
Food and culture writer, Michael Pollan, suggests that
corn is actually using us humans as a means to dominate
the world. Over the centuries of improvement, corn has
manipulated us to plant it over millions of acres, to be
dependent on it for food and related products, to
genetically modify it so that it makes its own
insecticide. Maybe Pollan is right. Corn is rapidly
becoming King Corn.
from humble Joint-tail Grass here in South Texas, we
connect to one of the most widely grown crops in the
world. Interesting, no?