Excerpts from Jim Conrad's
Naturalist Newsletter

from the August 7, 2011 Newsletter issued from written at Mayan Beach Garden Inn 20 kms north of Mahahual, Quintana Roo, México

The road between Mahahual and Sian Ka'an Biosphere Reserve skirts several little ponds with grassy margins. Some of those "grasses" are spectacular, and some aren't even grasses. For example, you can see a small part of a single clump about ten feet high (3m) and as wide as about three large refrigerators below.

Sawgrass, CLADIUM JAMAICENSE, plantlets

Besides its robust vigor, something catching my eye about this plant -- in the picture most easily seen in the bottom, left corner -- was how its leaning stems sprouted leafy plantlets for future vegetative reproduction. A close-up of a plantlet's knobby base is shown below:

Sawgrass, CLADIUM JAMAICENSE, plantlet base

The plants were a little past their flowering peak, but old inflorescences were still present, as seen below:

Sawgrass, CLADIUM JAMAICENSE, old inflorescences

Despite its outward appearance, this plant was not a grass -- not a member of the Grass Family, the Poaceae. Instead of its stems being round in cross-section, like those of grasses, they were triangular. Also, its flowers were not arranged in spikelets and florets the way grass flowers are. Our giant's tiny, messy-looking flowers are shown below:

Sawgrass, CLADIUM JAMAICENSE, flowers

This is a member of the Sedge Family, the Cyperaceae. That's a big family of about 5,500 species in 109 or so genera, centered mostly in tropical Asia and South America. To give you an idea of how the Sedge Family compares with the Grass Family, in my Flora of McLean County, Kentucky, done for my Master's thesis I listed 55 grass species, but only 33 members of the Sedge Family -- of which 22 were sedges, or members of the genus Carex.

The plant we're dealing with here, however, isn't a Carex or any genus found back in Kentucky. It's CLADIUM JAMAICENSE, known as Sawgrass, even though it's not a grass. Sawgrass is famous as being the dominant flowering plant in the Florida Everglades. When you see hovercraft skimming across the Everglades' "River of Grass, that "grass" is the Sedge-Family member Cladium jamaicense. You can see the tiny, sharp blade teeth behind the name "sawgrass" below:

Sawgrass, CLADIUM JAMAICENSE, teeth on blade margin

If a Sawgrass blade cuts at your hot, sweaty arm just right, a rather neat little bleeding cut results.

Sawgrass is such a robust, fast-growing plant that researchers are looking into its potential for producing ethanol fuel.

Many birds nest and feed in Sawgrass clumps, and various reptiles and amphibians find food and shelter there. The plant's seeds are abundant and nutritious. In the Everglades, Alligators use higher ground within Sawgrass stands for nesting sites.

Sawgrass is native from the Southern US through the West Indies, Mexico, and Central America into tropical South America. In this local area Sawgrass only spottily occurs, mostly at the bases of elevated roads crossing wetlands.

It's worth noting that not only have we seen that the dominant palm in our mangrove swamps is the Paurotis, Acoelorrhaphe wrightii, which is the characteristic palm of Florida's Everglades, but also our Sawgrass is the Everglades' most abundant flowering plant.