Grasses really are flowering plants

Grasses don’t get a lot of love. People walk on them, dogs do their business on them. If they get noticed at all it’s only for the time it takes the gardener to sigh or curse, depending on temperament, at how tall the grass has gotten before heading off to fire up the lawnmower. Even native gardeners like me often don’t bother to know the various species they might have in their yards, except for the showy ornamentals like muhly grass or purple lovegrass.

They’re so overlooked that people forget that they truly are angiosperms, flowering plants. I was reminded of this the other day when I was out chasing bugs for the camera and I noticed the exquisite flowers on a spikelet of grass in the back yard.

The species is the ubiquitous St. Augustinegrass, which is supposed to require a lot of care (read, fertilizing, weedkilling, pesticide applications, frequent mowing) if you want to use it as turf here in South Florida, as many homeowners do. My experience was completely different, however: all I had to do to get this grass to invite itself into my yard was mulch the back yard completely and then let it grow in. It came on its own, with no encouragement from me, and has been spreading in competition with two or three other species of  grass and a few nongrassy flowering ground covers like Mexican Clover (Richardia grandiflora). But it’s doing quite well, having conquered about half of the nonplanted area in my back yard, and it’s making good inroads into the clover-dominated terrain.

All this while I’ve been doing absolutely nothing that your typical lawn-happy homeowner does. Zip, zero, zilch, nada.

Of course, without all the fertilizer and weedkiller and other chemicals that I refuse to introduce into my local environment (my children play in this yard!), it’s not a beautiful monoculture turf, but that’s not really what I’m looking for in my native-planted back yard. And since I prefer the meadow to the golf course, I’ve let the grass grow up tall around the edges, where it grows the most beautiful little flowers, if you take the time to look closely enough.

See?

St. Augustinegrass flower

St. Augustinegrass (Stenotaphrum secundatum). Boca Raton, FL, May 22, 2013

Grass Terminology

I still haven’t mastered my graminology, so I have to have my references next to me when I write about it, but according to the dean of Florida botanists, and the first graminologist I’d ever heard of, Walter Kingsley Taylor, the flowering part of the grass you see pictured above is usually called the culm, and depending on species may be “single (simple) or branched (multiple)…creeping, ascending, spreading, erect, abruptly bent (geniculate), or prostrate (decumbent).” For this species, they are “branching, creeping, compressed, terminal and axillary.” (I think the comma after “compressed” is a typo.)

From just looking at the picture above, I can tell you in my own words (and then in translation to graminological terms) that I love the purple spikelets (stigmas), the gold whatzits (technically called anthers, familiar to those who know wildflowers), and the little white trailing whoozits (filaments). They sure are purty, ain’t they?

Many grasses propagate vegetatively. That means they spread by growing sideways, rather than needing to grow from seed. They spread vegetatively by two means: stolons, or aboveground runners, and rhizomes, or belowground runners. St. Augustinegrass sends out long aboveground runners, so it uses stolons.

Etymology

This genus’ name is derived fro the Greek words stenos, narrow, and taphros, trench. Again according to Taylor, this refers to the shallow cavities or depressions of the rachis. What’s a rachis? Well, according to our local graminologist, George Rogers up at Palm Beach State College (Palm Beach Gardens campus), this is:

Rachis: The stem of a spike or raceme—the stem of a branch within an inflorescence. Image from floridagrasses.org

The species name is Latin and has been adopted by botanists into the English word secund (not a typo): a botanical term used of plants when similar parts are directed to one side only, as flowers on an axis. (Lat. secundus, “following”). It’s not entirely obvious from my shot of the flowering St. Augustinegrass, but the flowers truly are on only one side of the “stem.” I had a hard time finding one of these in flower in the right light; most of them were on the shady side of the stem.

References

Bradford, J, G. Rogers, and J. Wilkinson. Grasses of Palm Beach and Martin Counties. floridagrasses.org.

Taylor, W. K. (2009). A Guide to Florida Grasses. Gainesville: U of Florida P.