Astragalus ceramicus var. filifolius (A.Gray) F.J.Herm.
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Authors
Rupert C. Barneby
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Authority
Barneby, Rupert C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13(1): 1-596.
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Family
Fabaceae
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Scientific Name
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Type
"Upper Louisiana, Bradbury."—Holotypus, labeled "Pursh’s specimen," PH! isotypus, NY (fragm. ex herb. Lambert.)!
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Synonyms
Astragalus pictus var. filifolius (A.Gray) A.Gray, Astragalus filifolius A.Gray, Psoralea longifolia Pursh, Orobus longifolius Nutt., Physondra longifolia (Pursh) Raf., Phaca longifolia (Pursh) Nutt. ex Torr. & A.Gray, Astragalus ceramicus var. imperfectus E.Sheld., Astragalus ceramicus var. longifolius (Pursh) Rydb., Astragalus angustus var. longifolius (Pursh) M.E.Jones, Astragalus longifolius (Pursh) Rydb., , Astragalus angustus var. imperfectus (E.Sheld.) M.E.Jones, Astragalus longifolius (Pursh) Rydb., Astragalus mitophyllus Kearney
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Description
Variety Description - Leaves 2.5-17 cm. long, commonly all reduced to the filiform rachis, only some lower leaves with 1-2 (3) pairs of lateral leaflets; racemes 2-7-flowered, the axis 1-4.5 (5.5) cm. long in fruit; calyx (3.7) 4-6 mm., the tube (2.3) 2.5-3.5 mm. long, 2.5-3 mm. in diameter, the teeth (1.4) 1.6-3 mm. long; banner 7.4-10.8 mm. long, 6.2-8.5 mm. wide; wings 6.9-10.6 mm. long, the claws 2.4-3.4 mm., the blades 4.6-8.2 mm. long, 2.3-4 mm. wide; keel 7-9.1 mm. long, the claws 2.5-3.4 mm., the blades 4.5-6.1 mm. long, 2.2-2.8 mm. wide; stipe of the pod 1.5-3 mm. long.
Distribution and Ecology - Dunes and sandy hollows in rolling plains, sometimes in sandy fields or on sand bars of intermittent streams, mostly below 7000 feet, locally plentiful in scattered stations over the higher Great Plains from western North Dakota and eastern Montana south through eastern Wyoming and Nebraska to the Arkansas Valley in Colorado and western Kansas, and south just into the Oklahoma Panhandle; in Colorado extending west up the Arkansas into Chaffee County and to San Luis Valley in Saguache County, there reaching 8300 feet.—Map No. 33.— Late April to July.
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Discussion
The var. filifolius is especially common on the sandhills of western Nebraska. The pod in this region is very large, up to 5 cm. long and proportionately swollen; elsewhere pods over 4 cm. long are rarely met with, but in other respects the plants of the prairie states do not vary greatly. All leaves, except a few of the lowest, are reduced to the unadorned rachis which may be truly filiform or a little dilated distally in the form of a linear leaflet. Thus the general aspect of the average plant is leafless and broomlike; the stems are weak and pliant, offering little resistance to the wind. Mention has been made already of a relatively leafy variant with pods of moderate size found on the east slope of the Rocky Mountains in southern Colorado at elevations near 8000 feet. This form, known from only three localities (Crestone, Saguache County, Ramaley & Johnson 14,836, NY; Buena Vista and Salida, Chaffee County, Ripley & Barneby 10,350, RSA & Clements 114, NY), deserves further study.
Few species, I suppose, have accumulated a more massive synonymy of the purely nomenclatural sort. All fifteen binomial and trinomial combinations listed above are based ultimately on Psoralea longifolia Pursh. At the time of its discovery the painted milk-vetch was an altogether unprecedented type of papilionaceous legume, and early transfers to Orobus and the specially created Physondra recall that fact. When compared subsequently with several of Nuttall’s leafless Homalobi, its affinity to Phaca and Astragalus became apparent, although it still differed from genuine Homalobus in its inflated fruit. Names proposed since 1864, when Gray consolidated these genera into Astragalus sens. lat., reflect the search for epithets acceptable in their category under rules of nomenclature which have shifted as often as the very sands in which the species grows.
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Objects
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Distribution
North Dakota United States of America North America| Montana United States of America North America| South Dakota United States of America North America| Wyoming United States of America North America| Nebraska United States of America North America| Colorado United States of America North America| Kansas United States of America North America| Oklahoma United States of America North America|