There is disagreement over the taxonomic treatment of Andropogon gerardii Vitman and Andropogon hallii Hack. They have been recognized either as distinct species or as varieties within a single species. Artificial hybridization experiments have shown that thee two taxa are completely interfertile, with offspring showing intermediate morphological characteristics. They do, however, show clear ecological differences - Andropogon gerardii is widely distributed in North America on moist prairie sites, while Andropogon hallii is restricted to drier, sandy soils in the Great Plains. Where their ranges overlap, however, they freely interbreed. In the Nebraska Sandhills, Andropogon gerardii occurs only in low meadows, while Andropogon hallii is restricted to upland sand dunes. Hybrids are found in narrow zones 5 -10 metres wide at the dune-meadow interface[].

Common Name: Big Bluestem

General Information

Andropogon gerardii is a perennial grass forming a tight clump of culms from a rhizomatous rootstock. These culms can be as little as 80cm tall in drier soils but up to 250cm in moister conditions[, ].
The plant was traditionally used as a medicine, though is little used nowadays. It is grown in soil stabilization projects and also as an ornamental grass, where it is valued for its attractive foliage which changes colour seasonally; its good architectural height; and its interesting flower/seed heads[].

Known Hazards

None known

Botanical References

,

Range

N. America - Saskatchewan to Quebec, south to Utah, Mexico and Florida; C. America - Mexico to Costa Rica

Habitat

Dry soils, prairies, open ground and open woods[, ]. Characteristic of climax grasslands throughout the tallgrass prairie region; it once blanketed the region, often comprising 70 - 90% of the vegetation[]

Properties

Medicinal Rating
Other Uses Rating
Habit	Perennial
Height	2.00 m
Pollinators	Wind
Cultivation Status	Ornamental, Wild

Cultivation Details

Andropogon gerardii has a wide native range, growing from the prairies of southern Canada to higher elevations in the tropical regions of MesoAmerica. In the temperate zone it is found in areas where annual daytime temperatures are within the range 10 - 20°c, but can tolerate 3 - 28°c[]. When dormant, the plant can survive temperatures down to about -15°c, but young growth can be severely damaged at -5°c[]. It prefers a mean annual rainfall in the range 700 - 1,200mm, but tolerates 350 - 2,800mm[].
Requires a light porous sandy soil in full sun[]. Easily grown in average, dry to medium, well-drained soils in full sun[]. The plant is tolerant of a wide range of soils and growing conditions[]. It puts out lots of growth in moist, fertile soils, but is less apt to topple in dryish, infertile soils[]. It prefers a pH in the range 5.5 - 6.5, but tolerates 4.5 - 7.6[]. Established plants are very drought tolerant[].
The plant freely self-seeds in optimum growing conditions[].
It develops an extensive root system and is somewhat slow to establish, but, once established, is easy to maintain[].
A very ornamental plant, it forms large clumps, spreading by short stolons[]. Various cultivars have been developed, many of these especially for use in rehabilitating prairie land with native grass species[].

Edible Uses

None known

Medicinal

The plant is analgesic, carminative and diuretic[].

A decoction of the roots is used in the treatment of stomach-aches and flatulence[, ].

A tea made from the leaves is used as a wash to relieve fevers and general debility[, ].

Agroforestry Uses:

The plant has an extensive root system which makes it useful for soil stabilization[].

Other Uses

None known

Propagation

Seed - surface sow in early spring in a greenhouse. When large enough to handle, prick the seedlings out into individual pots and grow them on for the first winter in a cold greenhouse. Plant out in late spring or early summer, after the last expected frosts.
Division in spring.