Not Just Any Old Grass

The four primary grasses in the Tallgrass Prairie are Big Bluestem, Little Bluestem, Indiangrass and Switchgrass. A number of grasses could be considered primary riparian grasses. An excellent riparian grass must grow well in shade or partial sun, have deep, strong root systems capable of stabilizing the soil, thus preventing erosion, and be capable of growing in the moist soil of stream banks and in the overbank zone.

I would include Switchgrass, Inland Sea Oats and Eastern Gamagrass among the top candidates as primary riparian grasses. Each of these three grasses have their own unique characteristics.

Eastern Gamagrass (Tripsacum dactyloides) is a bunch grass that is a close relative of corn. Like corn, it is monoecious, meaning it has separate male and female flowers on the same plant. Unlike corn, the male and female flowers are on one continuous spike with the male flowers at the distal (outer) end of the spike.

The female flowers, located immediately below the male flowers on the spike, produce stacked yellow kernels that closely resemble corn kernels when ripe.

In addition to being an excellent soil stabilizer, Eastern Gamagrass is an important food source for both birds and mammals.

This set of photographs was taken along the Mission Reach of the San Antonio River near the Roosevelt Park Trailhead on Thursday, October 31, 2013.