Post by: Wes Hauser ’15
The Prairie Dropseed (Sporobolus heterolepis) is a fantastic member of the grass family, Poaceae, that can be seen in bloom in front of the Wabash College Fine Arts Center. Like other members of the Poaceae, S. heterolepis has quite the unusual floral structure and arrangement. Its flowers are organized into what are called florets which have 2 outer organs called the palea and the lemma with stamens and carpels (plant reproductive organs) housed within (see the diagram below, borrowed from floridagrasses.org). These florets are then organized along the grass’s reproductive axis (inflorescence) as a spikelet. Be sure to also check out the close-up pictures of spikelets from S. heterolepis! They’re pretty cool and look strikingly similar to those of Eragrostis, the genus of grasses I’ve been working with in Professor Ingram’s lab this summer. Unsurprisingly, Eragrostis and Sporobolus are closely related and are often confused for one another by amateur taxonomists.
Sporobolus heterolepis is a perennial plant that has a large native range in the United States– it can be found in most states in the Midwest and along the eastern seaboard. Like other members of the Chloridoideae, S. heterolepis undergoes C4 photosynthesis, where carbon fixation is spatially separated at the cellular level to make photosynthesis more efficient. This makes the Prairie Dropseed quite drought tolerant and a great candidate for prairie restoration projects. It is particularly useful in these situations because it is a great indicator of ecosystem vitality. Its emergence and success after a wildfire or control burn often signals the reestablishment of other prominent prairie flora such as the Big Bluestem (Andropogon gerardii) and Indian Grass (Sorghastrum nutans).
Prairie Dropseed also has several other interesting uses– the seeds were once used by the Native Americans to make flour, it is continuously prized for its landscaping capabilities, and some even say the seeds smell like popcorn! So if you see this shrub growing in its usual bunching habit, try taking a whiff if you’re not entirely convinced!