Muhlenbergia wrightii

Spike Muhly

Just a pretty picture of Muhlenbergia wrightii.

A field of dry Spike Muhly. Note the thick clumps, these over a foot in diameter.

Closer view of seedheads. The separated basal seedhead bits are short branches, so these are not true spikes!

These seedheads show the typical texture of Spike Muhly. There are no awns.

This row of seedheads shows the best diagnostic feature of Spike Muhly: the basal gap(s) in the continuity of the column.

Sometimes the seedheads are shorter. The interruption at the column base is characteristic but not ubiquitous.

It's the interuption in the base of the seedhead!

Spike Muhly leaves are quite short compared to many grasses.

These massive roots show that the Spike Muhly is a perennial.

How to Identify Spike Muhly

  Spike Muhly is a perennial bunchgrass. Its seedheads are usually about 2 to 6 inches long. It is not the only spike-like grass in Arizona that usually has a break or two in the seedhead, but it is the most common. The separate basal outliers are actually branches, so this is not a true spike. On true spikes all spikelets emerge directly from the rachis (the seedhead stem). Even when fresh, Spike Muhly seedheads look gray.

Similar Species

  A person could call Spike Muhly an elongate, cylindrical puff, and I believe I will. Phleum pratense (Timothy) is similar but has no seedhead gaps. When Junegrass is in its spike-like form, before opening out to a panicle, it can have breaks in the seedhead. It is a different color and shinier, ...or you can check its longer, appressed branches.