Dalea lanata var. lanata
Rupert C. Barneby
53a. Dalea lanata Sprengel var. lanata
(Plate LXII)
Stems commonly glandless or nearly so; vesture of stems and leaves always dense, relatively long, the longer hairs (often on the upper leaf-surface) up to 0.3-0.7 mm long; calyx-tube 2.2-2.5 mm, the longest (dorsal) tooth 1.5-2.1 (2.3) mm long; petals relatively large, the blades of the epistemonous ones 2.8-3.8 mm long; 2n = 14 (Mosquin).—Collections: 49 (iv).
Deep sandy soils, usually on hummocked dunes or drift-sand plains, near sea-level in s. Texas up to ± 1260 m (4200 ft) in the interior, forming extensive colonies but local and discontinuous, Pecos Valley in s.-e. New Mexico n. to the upper Canadian, Cimarron, and Arkansas rivers in s.-e. Colorado, s.-w. Kansas, and the Oklahoma Panhandle, downstream interruptedly along the Arkansas to Pulaski County, Arkansas, and e. in Texas through the Panhandle and Red River drainage to the upper Brazos and Trinity valleys in n.-centr. Texas; one old record from the North Platte in n.-e. Colorado (Dr. James); disjunctly on the Gulf Coastal Plain, in sandy live-oak woodland, in Kenedy, Brooks, Jim Hogg, and Starr counties, s. Texas. — Flowering in spring and summer n.-ward, intermittently through the fall s.-ward.—Representative: Colorado: W. A. Weber-5141. New Mexico: Fendler 128 (NY, UC); Ripley & Barneby L\817 (CAS, NY, US); Mosquin et al. 6938 (DAO, NY). Kansas: Rose & Fitch 17,033 (NY, US); Rydberg & Imler 780 (NY), 925 (NY). Oklahoma: G. W. Stevens 1080 (NY); Goodman & Kelting 5331 (NY). Arkansas: Demaree 8697, 8724 (NY). Texas: McVaugh 7253 (NY); Lundell 13,068 (NY, UC); Hinckley 3070 (NY); D. & H. Correll 10,661, 33,014 (RENNER).
Dalea lanata (woolly) Spreng., Syst. Veg. 3: 327. 1826.— "Ad fl. Arkansa Amer. bor."—No typus known to survive, and no collector mentioned in the protologue, but from the circumstances and date certainly described from an isotypus of the next, sent to Sprengel by Nuttall. — Parosela lanata (Spreng.) Britt., Mem. Torrey Club 5: 196. 1894.
Dalea lanuginosa (woolly) Nutt, ex T. & G., Fl. N. Amer. 1: 307. 1838. "Gravelly banks and islands of the Arkansas, near Fort Smith, Nuttall! On the Platte, D. James!" — Holotypus, "Dalea *lanuginosa. Arkansa. Nuttall," BM! isotypi, GH, NY (2 sheets, one ex herb. Torr., one a dupl. ex herb. Nutt. BM)! paratypus (James), NY!
This is a graceful but not a showy plant, found only on dunes or deep sandy soils, sometimes associated northward with D. villosa and on the coastal plain of Texas with D. obovata and D. aurea. It has a characteristic habit, the solitary or few stems branching as they rise from the sand into openly fanshaped sprays of gray or silvery foliage, the leaves all displayed so as to face the zenith. The flowers are vivid in hue but small and fugitive; few open at any one day, and their little epistemonous petals, best seen in the early hours, fall from their high perch on the androecium a few hours after the column expands. The flower suggests, except for the free keel-petals standing below the exposed tassel of golden anthers, that of several Mexican species of Marina, but the sessile calyx, paired ovules, and chromosome number are all in accord with Dalea.
The range of var. lanata is notably discontinuous, like that of Astragalus ceramicus Sheld. patterned and limited by the selective dune habitat. There seem to be no modern collections from north of the Arkansas River in western Kansas and the head of the Cimarron in s.-e. Colorado, nothing to confirm Dr. James’s discovery on the South Platte in 1820. The stations in the state of Arkansas are situated directly on the eponymous river where the species is most probably an old immigrant, water-borne from upstream. The populations isolated out on the Coastal Plain in southern Texas seem not to differ in any appreciable way.
References: [Article] Barneby, Rupert C. 1977. Daleae Imagines, an illustrated revision of Errazurizia Philippi, Psorothamnus Rydberg, Marine Liebmann, and Dalea Lucanus emen. Barneby, including all species of Leguminosae tribe Amorpheae Borissova ever referred to Dalea. Mem. New York Bot. Gard. 27: 1-892.Multimedia:
