Astragalus schmollae Ced.Porter

  • Authors

    Rupert C. Barneby

  • Authority

    Barneby, Rupert C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13(1): 1-596.

  • Family

    Fabaceae

  • Scientific Name

    Astragalus schmollae Ced.Porter

  • Type

    "Northwest of Spruce Tree House, Mesa Verde National Park, 6800 feet, May 26, 1925, Hazel M. Schmoll & Deric Nusbaum 1555 (Rocky Mountain Herbarium no. 105889, flowers, no. 105888, fruit)."—Cotypi, RM!

  • Synonyms

    Astragalus platycarpus var. montezumae Barneby

  • Description

    Species Description - Tall and robust, strigulose throughout with fine, appressed hairs up to 0.40.55 mm. long, the stems green or purplish at base, the herbage cinereous, the leaflets pubescent on both sides, the inflorescence± black-hairy; stems few, erect and ascending from the shallowly buried root-crown, 3—6 dm. long, ribbed and fistular below, shortly branched at 1-4 nodes preceding the first peduncle, the internodes below the first branch mostly short and lacking developed leaves, the upper ones much longer, flexuous; stipules 2-7 mm. long, dimorphic, the lowest papery, castaneous or purplish-brown, adnate to the vestigial petiole to form an obtuse or bidentate sheath, decurrent around Vi to nearly the whole stem’s circumference, the median and upper ones herbaceous, obscurely adnate, with deltoid- acuminate, triangular, or lanceolate, mostly deflexed blades; leaves 4-10 cm. long, shortly petioled or the uppermost subsessile, with (7) 11—21 opposite or scattered, linear, linear-oblong, or -elliptic, obtuse or retuse, flat leaflets 6—25 (30) mm. long, all articulate; peduncles erect, 9—21 cm. long, the first 1 or 2 usually very stout and long, the inflorescence mostly projected well beyond the main stem-axis; racemes loosely (7) 10—28-flowered, ultimately secund, the axis (2.5) 4.5— 20 cm. long in fruit; bracts membranous, lanceolate or lance-ovate, 1.5—3 mm. long; pedicels at anthesis 1—1.3 mm. long, in fruit widely spreading, arcuately recurved, or deflexed, a trifle thickened, 2-2.5 mm. long; bracteoles 0-2, minute when present; calyx 6-7.5 mm. long, rather densely and loosely black-strigulose, the slightly oblique disc 1-1.2 mm. deep, the cylindric or cylindro-campanulate tube (5) 5.5-6 mm. long, 2.6-3.2 mm. in diameter, the triangular-subulate teeth 1-1.7 mm. long, all crowded toward the dorsal side of the calyx, the ventral sinus wide and deeply cut back; petals ochroleucous, concolorous; banner recurved through ± 45°, rhombic-elliptic, deeply notched, 14.5-18 mm. long, ± 7-8 mm. wide; wings 13.5-17 mm. long, the claws 6-6.7 mm., the oblong-oblanceolate, obtuse, sometimes very obliquely truncate, or shallowly emarginate, nearly straight blades 8-11.8 mm. long, (1.5) 2.3-2.5 mm. wide; keel 9.5-11.5 mm. long, the claws 5.7-6.5 mm., the lunate blades 4.6-5.8 mm. long, 2.4-2.9 mm. wide, incurved through 95° to the broadly triangular, obtuse, obscurely porrect apex; anthers 0.6-0.65 mm. long; pod pendulous, stipitate, the straight, slender stipe 5-10 (12) mm. long, the body linear-oblanceolate in profile, (2.5) 3-4 cm. long, 3.5-5 mm. in diameter, nearly straight to gently decurved, tapering gradually downward into the stipe, shortly acuminate or cuneately acute and cuspidate at apex, obcompressed-triquetrous, with low-convex lateral and shallowly but narrowly grooved dorsal faces, carinate ventrally by the prominent, thick suture, the thinly fleshy, green, strigulose valves becoming stiffly papery, stramineous, cross- reticulate; ovules 18-20; seeds (not seen quite ripe) ± 3 mm. long.

    Distribution and Ecology - Sandy and gravelly flats and terraces, among junipers and piñons, on sandstone, 6800-7000 feet, locally abundant but known only from the plateau at the south end of Mesa Verde, Montezuma County, Colorado.—Map No. 23.—May and June.

  • Discussion

    The Schmoll milk-vetch might be described as a foliose version of A. lonchocarpus, having quite similar flowers and fruits but all the leaves regularly odd-pinnate and all leaflets petiolulate. The calyx of A. Schmollae tends to be shorter in relation to the petals, and the pod is uniformly pubescent and more narrowly grooved along the back. The known range of the species extends little over a mile or possibly two in diameter, but the plants are abundant locally in gravelly openings among the nut pines and junipers about the aboriginal dwellings. Northward on the Mesa, in oak brush at slightly greater elevations, A. Schmollae is abruptly replaced by the superficially similar A. scopulorum, which may be recognized by its truly connate stipules and sharply trigonous, laterally compressed pod.

    Although only described in recent years, A. Schmollae was first collected in 1890 by Alice Eastwood. Her specimen (US), taken in July, was too far advanced to show the full characters of the species, but Jones recognized it as a relative of A. Coltoni and Rydberg identified the detached fruit as that of A. lonchocarpus.

  • Distribution

    Colorado United States of America North America|