Bouteloua curtipendula

Side-oats Grama


View of Bouteloua curtipendula or Side-oats Grama

Car-side view of Bouteloua curtipendula, common name Side-oats Grama.

 Closer View of Inflorescence

The inflorescence of Side-oats Grama. The spikelets that appear attached directly to the rachis. However, they are actually on tiny, short branches, so this is a spike-like seedhead, not a true spike.

Even closer View

The "branches" often droop or extend straight out. Yes, the tiny teeth sticking out from the rachis are actually branches.

Red Inflorescences

Sometimes the seedheads are red, sometimes green. Here you can see very tiny red anthers--the grass was in anthesis, spreading pollen.

 Two Green Seedheads

Here are two of the more common green spike-like panicles of Bouteloua curtipendula.

 Sparce Versus Crowded Spikelets

The left-hand inflorescence has very sparce spikelets. It makes the seedhead appear quite different from those with crowded spikelets.

Bright Red Anthers

These Side-oats Grama spikelets were in anthesis, and the usually-yellow anthers are bright red.

 Roots of Side-oats Grama

Roots of Bouteloua curtipendula are bushy as are the dense, thick above-ground clumps of this grass.

 Enhanced View of Spikelets

An enhanced view of the barely-visible, tiny branches shows that there are several spikelets on each branch. Each pointy thing is a floret, some of which have very short awns.

How to Identify Side-oats Grama

  This is the most common of the similar "sideoats" gramas and one of the most common grasses in Arizona. Side-oats Grama grows medium-high: usually knee-high to hip-high. The spikelets can be red or green as you have seen and they tend to droop downward. Side-oats Grama is perennial.


Similar Species

  There are five other "sideoats" type gramas in Arizona, so this one would not be listed as an easy grass except that it is so common and the others are not. Watch out especially for Bouteloua aristidoides (Needle Grama), which has generally fewer and much longer branches (to 1/4 inch or more) holding its undrooping spikelets. The other look-alikes have bushier spikelets with longer awns, and are mostly restricted to southeast Arizona.

  Porter's Melic (Melica porteri) is rather similar in that it consists of short branches on one side of the rachis. It occurs only in southeast Arizona.