Deertongue is native to eastern North America. It prefers partially sunny sandy, acidic soils, such as woodlands, savannas, swamps,
and stream and pond boundaries.
Plants: Plants are 1½-4½′ (45-137 cm) tall, unbranched
at first, branching occasionally during the fall. Spreading via their root systems as well as by
seed, they often
appear in clonal clusters. Stems (culms) are hairy.
Leaves: Five to ten clasping, alternate leaves occur along the stem.
Each leaf is up to 10″ (25 cm) long × 1″ (3 cm) wide, and lanceolate,
widest about a third of the way from the stem and tapering to a sharp tip. They may have a
few thin hairs, increasing in density closer to the stem. Veins are parallel to the long dimension.
Flowers: There are two types of flowerheads.
Topping the main stem is a panicle that branches into many fine wavy spikelets tipped by flowers that
are open, available for pollination. These flowerheads are prominant, 2½-6″ (6.3-15 cm) in size, and
distinctive.
Hidden in the leaf sheaths of secondary branches that appear during the fall are a second type of
flowerhead, containing cleistogamous flowers, that is, flowers that never
open, instead fertilizing themselves. Flowers appear from June to September.
Fruits: Seeds are ~1/16″ (2-2.5 mm) long, ovoid in shape,
and somewhat flattened, in green or purple husks.
Medical: Deertongue has been used to help treat
malaria, but it contains coumarins, which thin the blood and cause liver damage.