Chenopodium subqlabrum (Wats.) A. Nels. 



Chenopodiaceae 



Smooth goosefoot 



A. Description 



1. General description: Annual herb, with a wide range in 

 branching forms and stature depending on site conditions, 

 typically 7.6-20.3 cm (3-8 in) tall. Blades linear, entire, 

 green and glabrous, with a single vein from base, up to 2.5 cm 

 (1 in) long. Infloresence of remote, small, compact cluster 

 of flowers (glomerules) . Sepals five, glabrous, exposing a 

 jet-black fruit at maturity; stamens five; stigmas two. 

 Fruits containing a seed that readily detaches from the 

 surrounding pericarp. 



2. Technical description: Annual, stem solitary or branched 

 from base, sometimes branched above, up to 8 dm tall. Blades 

 linear, entire, to 3 cm long, with single vein from base, 

 glabrous, exposing fruit at maturity; stamens 5; stigmas 2. 

 Fruits horizontal, 1.2-1.6 mm in diameter, pericarp readily 

 separable from seed (Great Plains Flora Association 1986) . 



3. Diagnostic characteristics: Chenopodium subqlabrum 

 sometimes occurs with and is most closely related to C. 

 leptophyllum , a widespread species that is sometimes 

 adventive. They both have linear, single-veined leaves but 

 the leaves of smooth goosefoot are glabrous rather than 

 farinose white. Smooth goosefoot typically has a highly- 

 branched growth form with widely-spaced glomerules compared to 

 the slender form and tight infloresence of C. leptophyllum 

 with a single axis. They are technically distinguished by 

 characters that require a hand lens: smooth goosefoot has a 

 readily detachable pericarp, instead of an attached pericarp. 



B. Present legal or other formal status 

 1. Federal 



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

 is imperiled in Canada (Argus and Pryer 1990) . In the 

 United States, it is possibly a Great Plains endemic, but 

 annotation of reported specimens in the midwest and 

 northwest is needed to clarify distribution if not 

 taxonomy. Recent repeated collections in eastern Wyoming 

 cast doubt the appropriateness of recommending it as a 

 candidate for federal listing (Hartman pers. commun.). 



B. U.S. Forest Service: None for South Dakota; 

 sensitive for North Dakota. 



C. Bureau of Land Management: none 



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