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Published In: American Journal of Botany 71: 285. 1984. (Amer. J. Bot.) Name publication detail
 

Project Name Data (Last Modified On 7/9/2009)
Acceptance : Accepted
Project Data     (Last Modified On 7/9/2009)
Status: Native

 

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2. Calamagrostis porteri A. Gray ssp. insperata (Swallen) C.W. Greene (Ofer Hollow reedgrass)

Pl. 133 a–d; Map 540

C. insperata Swallen

Plants forming loose colonies of scattered tufts. Flowering stems 25–100(–120) cm long. Leaf sheaths glabrous or less commonly with a line or band of minute, appressed hairs at the tip, the ligule 3–8 mm long. Leaf blades 3–40 cm long, 3–12 mm wide, flat, bluish green, glaucous on both surfaces. Inflorescences 10–30 cm long, open to dense, but not spikelike, the branches ascending at maturity, the longest branches more than 2 cm long. Glumes 3.5–6.0 mm long, elliptic‑lanceolate, tapered to a sharp point at the tip, roughened along the midnerve. Floret with the basal tuft of hairs about 1/2 as long as the lemma. Lemma 3.0–4.5 mm long, narrowly ovate, the awn attached toward the base of the midnerve, abruptly twisted and bent near the middle. 2n=56. July–September.

Scattered in the Ozark Division (Ohio, Indiana, Kentucky, Illinois, Missouri, and Arkansas). Shaded ledges and tops of bluffs with mesic upland forests, usually on acidic substrates, often on north‑facing exposures.

Van Schaack (1954) and Steyermark (1963) cited only two 1930s specimens from Douglas and Ozark Counties to support the inclusion of this taxon in Missouri (a third specimen from Texas County went unnoticed at the time). Periodic searches by a number of botanists failed to relocate these plants in nature, and the taxon was presumed to have become restricted to the few extant populations in southern Ohio. However, in 1990, during a Missouri Natural Features Inventory of Texas County (Ryan and Smith, 1991), Bill Summers located a new population. The insights from this find led to the rapid discovery of additional populations (mostly by keen‑eyed Summers). Amazingly, by 1996, about 80 populations had been documented as growing in the state. The secret to these finds is that C. porteri exists mostly as vegetative colonies, with flowering uncommon and very sporadic. Even when they flower, plants fail to produce mature fruits, for reasons that are not presently clear (most populations may consist of individual, self‑incompatible clones or there may be other genetic barriers to seed set). Vegetatively, the plants are distinct within their habitats. They occur as large, loose colonies of scattered tufts and are characterized by long rhizomes, membranous ligules, and glaucous, bluish green herbage. Other bluish green species, such as some species of the wild rye genus Elymus, have shorter ligules, lack well‑developed rhizomes, and occur as tufts or clumps. Agrostis perennans (Walter) Tuck., upland bent, another bluish green species with membranous ligules, has narrower leaf blades, and thinner stems that sometimes root at the lower nodes, but also lacks rhizomes.

The other subspecies, ssp. porteri, is a high polyploid (2n=84–104) that differs morphologically from ssp. insperata in its light green herbage and leaf sheaths with a dense beard of long, spreading hairs at the tip (Greene, 1980, 1984). It is distributed mostly in the Appalachian Mountains from New York to Virginia and with western outliers in Kentucky and Tennessee. The two subspecies occur in relatively close proximity in western Kentucky.

 


 

 
 
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