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Andropogon gerardii Vitman

Kingdom: Plantae Rank: Species Parent: Andropogon Status: Invalid Reason: unverified

Common Names:

  • BIG BLUESTEM - English, United States of America

Morphological Description

Diagnosis: Plant to 2 m tall, essentially glabrous, often glaucous; inflorescences of 2–7 digitately arranged branches, the branches 4–11 cm long; sessile spikelets usually scabrous, often glaucous; upper lemma of sessile spikelet awned (sometimes awnless in subsp. hallii); pedicellate spikelets about as large as sessile, awnless. Aug–Nov.


Notes: This polyploid species has chromosome numbers of both 2n = 6x = 60 and 2n = 9x = 90; the plants are virtually indistinguishable morphologically (Norrmann et al. 1997). Hybridization between these two main cytotypes is possible, with the resulting individuals having a range of chromosome numbers (Norrmann & Keeler 2003). The reproductive biology of this species was studied by McKone et al. (1998) and was found to be very unusual in allocating more resources to male reproduction (pollen production) than to female reproduction (seed production). (gerardii: for Louis Gérard, 1733–1819, French botanist)