RESULTS - SOUTH DAKOTA 



Aster paucif lorus Nutt. 



Asteraceae; Astereae Tribe 



Marsh alkali aster 



A. Description 



1. General description: Perennial herb arising singly from 

 a rhizome, often in clumps, stems branched above, 10.2-50.8 cm 

 (4-20 in) tall. Leaves linear, up to 5.1 cm (2 in) long and 

 less than .64 cm (1/4 in) wide, often appearing succulent to 

 fleshy. Infloresence few-headed (usually less than 10) at 

 ends of branches, ray flowers blue to light pink, involucral 

 bracts glandular (from Van Bruggen 1985) . Collection dates of 

 the three Harding County records are all between July 15-3 0, 

 though it apparently has indeterminate flowering and may bloom 

 between July-September (Great Plains Flora Association 1986) . 



2. Technical description: Glabrous perennial 2-4(6) dm tall, 

 arising from a creeping rhizome. Leaves cauline, linear to 

 linear-lanceolate, the prominent ones 3-4(9) cm long and 3-45) 

 mm wide, glabrous, entire, somewhat firm and fleshy, the 

 uppermost reduced and bractlike. Infloresence an open, 

 corymbiform cluster of (1)3-8 heads; involucre 4-7 mm tall, 

 glandular; involucral bracts imbricated in 2 or 3 series, 

 lanceolate; ray florets 15-25, ligule blue or purple to light 

 pink, 5-7 mm long; disk florets with corolla yellowish or 

 white. Achenes pubescent, ca 2 mm long; pappus of numerous 

 white bristles 3-6 mm long (Great Plains Flora Association 

 1986) . 



3. Diagnostic characteristics: Marsh alkali aster 

 superficially resembles common asters of western South Dakota 

 in having distinct ray flowers, and narrow leaves which are 

 not clasping. The key character, as reflected in the species 

 epithet, is the few-flowered infloresence, with less than 10 

 heads vs. 20 or more for Aster ericoides , A. falcatus and A. 

 pansus . The leaves of Marsh alkali aster have a succulent 

 appearance, unlike all other asters. It is also highly 

 restricted in its habitat compared these other prairie asters, 

 being restricted to alkaline flats and extremely dry settings. 



B. Present legal or other formal status 

 1. Federal 



A. U. S. Fish and Wildlife Service: none 



B. U.S. Forest Service: none 



C. Bureau of Land Management: none 



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