It was fasciation, I know*
If the seed head of eastern gamagrass shown in a recent post was deformed, so was the stalk of the Liatris mucronata plant shown here, which I found growing on the prairie in far north Austin on August 2. In contrast to the eastern gamagrass, this plant was suffering from what botanists call fasciation, a word based, with some imagination, on the Latin fascia that meant ‘a strip of material, ribbon, band, bandage, swathe.’ As Dr. T. Ombrello wrote: “One interesting type of mistake that is occasionally found in plants is known as a fasciated or crested growth form. It is usually the result of a growing point changing from a round dome of cells into a crescent shape. Subsequent growth produces a flat stem. In some cases fasciation is the result of several embryonic growing points fusing together, with the same flat-stem appearance.”
The deformed flower stalk of eastern gamagrass shown in the recent post was one of a kind: the other nearby plants of that species were normal. In contrast, the Liatris mucronata in today’s photograph was one of several fasciated plants of that species growing in close proximity.
Update: see the following post to compare a few normal spikes from this species.
* The title of today’s post is an allusion to the classic song that begins with the line “It was fascination, I know.”
© 2011 Steven Schwartzman