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Excerpts from Jim Conrad's
Naturalist Newsletter
from the August 11, 2008 Newsletter, issued from the forest near Natchez, Mississippi; elevation ~400ft (120m), ~N31.47°, ~W91.29°:
INDIAN WOOD OATS
The grass shown above is one of the most graceful, common and easy-to-identify of all wild grasses. It's CHASMANTHIUM LATIFOLIUM, going by such English names as Indian Wood Oats, Wild Oats, Spangle Grass and many others. It used to be placed in the genus Uniola.
In the picture the plant arches from one of Sandy Creek's steep, overgrown banks, its leaves and flower heads quaking in a soft breeze flowing up the stream. Those flattish items at the end of the arcing stem are its flower heads.
Below you can see a close-up of a spikelet:
When I started learning my grasses back on the farm in Kentucky, this was the first species I was able to identify with certainty using technical keys, so I've always had a special place in my heart for this species. It was my "first grass" because its flowers are much larger than those of most grasses, so the parts were much easier to see and interpret than the flowers of most grasses.
For example, in the above picture notice that the spikelet consists of about ten teardrop-shaped items, which are the actual flowers, or florets. The very top of the spikelet is crowned by small, leaflike scales. These two scales are "glumes," and when you're identifying grasses the glumes' disposition, size, texture and other features are critically important.
Each of the ten or so florets below the glumes is encased in a scaly, scoop-shaped husk referred to as the "lemma." Lemmas are analogous to the calyxes of a regular blossoms. Indian Wood Oats' lemmas, my Gray's Manual of Botany says, are "hispidulous on the winged keel." It's referring to the fact that the lemma's flattish sides are folded together beneath a crease so sharp-edged that it's like a wing. "Hispidulous" describes to the tiny, silvery, slender hairs barely visible along the lemmas' winged keels.
Inside the lemmas are even tinier and more elegant details, for that's where the sexual parts are.
In fact, studying grass flower-anatomy thrusts your mind among such unforeseen and pleasing-to-the-eye details that one can't help but to be cast into a good mood. Inside the flower of every grass there's a wonderland of exotic forms, textures, colors and processes.
You might enjoy looking over my Grass Flower Page at http://www.backyardnature.net/fl_grass.htm.