I spent several days in the Bootheel of Missouri, last week. I ran across many new and exciting plants in this northern-most extension of the Mississippi embayment. Treats like Quercus nuttallii, Q. pagoda, Q. phellos (The Brian Fellows Oak), Q. falcata, Q. lyrata, Q. michauxii, Fraxinus profunda, Styrax americana, Leersia lenticularis, Carex reniformis, Brunnichia cirrhosa, Iris fulva, Gleditsia aquatica and Juncus nodatus were quite common.
While driving along back roads through the Mingo Swamp, I kept seeing this large Juncus in open areas. Finally, I decided it just might not be the large J. acuminatus I convinced myself it was. So, I pulled over for a closer look. As I stood next to the plant I was shocked to find it reached the height of my chin (5 ft and then some). Upon examination of the flower, I realized it was no Juncus. A long, hard style projected from involucral scales. I gave the exerted style a tug and found the other end attached, to an achene the size of a rice krispie. I galloped back to the truck and feverishly flipped through the Flora of Missouri (vol. 1) for answers.
The gelatinous depths my brain knew it was a Rhynchospora with its tuberculate style and overall architecture, but I wouldn't listen. It was just too big! I wanted it to be a Scirpus. After several failed attempts at an identification under Scirpus, I gave in and tried Rhynchospora. The first couplet made sense; the leaf blades were 8-20mm wide. The second couplet also fit; the perianth bristles were 2-4mm long. Alas, the giant sedge had a name, Rhynchospora corniculata!
Following Keith's tradition of providing english interpretations of scientific names, Rhynchospora means "nose seed" (perhaps why they are called "Beak Rushes") and corniculata means "horned". Both are apt descriptions of the long-horned style of this crazy-big sedge. It is a species of swamps throughout the southeastern United States.