Dalea frutescens
Rupert C. Barneby
57. Dalea frutescens Gray
(Plate LXIV)
Slender, intricately branching shrubs up to 3-8 (12) dm tall, glabrous up to the nearly always thinly or minutely pilosulous axis of the flower-spikes, the branches either erect and ascending or decumbent at base and then commonly layering and thence incurved-ascending, thereby forming small thickets, the older stems pale brown furrowed, the new twigs greenish or livid, at least distally gland-tuberculate, the foliage green, the leaflets thick-textured, ± bicolored, brighter green above, paler and punctate beneath; leaf-spurs 0.2-1 mm long; stipules subulate to narrowly triangular-acuminate, subglandular becoming dry and papery, 0.3-1.3 mm long; intra- petiolular glands 0; post-petiolular glands conic, prominent; leaves shortly petioled, the main cauline ones 1-2 cm long, with narrowly margined, ventrally grooved, punctate rachis and 4-9 (10) pairs of obovate to broadly oblanceolate and obtuse to emarginate, or obcordate, mostly navicular but not tightly folded leaflets 1.5-3.5 (5) mm long, the rameal and spur-leaves shorter, with fewer smaller leaflets, the terminal leaflet of all leaves sessile; peduncles leaf-opposed and terminal to all ultimate branchlets, 0.2-4.5 (5) cm long; spikes (3) 6-25 (30)-flowered, most commonly subcapitate to moderately dense and oblong, rarely loose (calyces finally up to 2-4.5 mm apart), the pilosulous (rarely glabrous) axis becoming 2-25 (35) mm long; bracts deciduous from peglike spurs, broadly ovate and short-acuminate to merely gland-mucronulate, less often ovate and long-acuminate, navicular and enfolding the buds, 2.2-3.4 (4.5) mm long, glabrous or nearly so and gland-pustulate dorsally, commonly ciliolate near base, thinly pubescent within; calyx 3.8-4.2 mm long, the shallowly pleated, lustrous, glabrous tube 2.6-3.2 (3.5) mm long, the reddish or concolorous ribs becoming prominent, the rather firm intervals charged with ±3-5 (7) elliptic, red or orange blister- glands, the orifice silky-ciliolate, the teeth deltate-acuminate to broadly triangular or low-deltate, often gland-spurred, the dorsal one 0.5-1.2 mm long, the ventral pair broader and shorter; petals bicolored (exceptionally all white), the banner whitish with green-yellow eye but early rubescent, the vivid pink-purple epistemonous ones perched 1.5-3.5 mm above hypanthium, all eglandular or the banner and keel rarely gland-tipped and the banner charged with a small gland-crescent; banner 5.1-6.2 mm long, the claw 2.4-2.9 mm, the ovate-cordate, hooded blade recurved through 50- 80°, deeply recessed at base into a comet, 3.2-4.2 mm long, 3.4-4.6 mm wide; wings 5.5-6 mm long, the claw 1-1.6 mm, the ovate-oblong blade 4.3-5.2 mm long, 2.7-3 mm wide; keel 6.5-8 mm long, the claws 1.5-2.2 (2.4) mm, the ovate-elliptic blades (5) 5.3-6.5 mm long, 3.3-3.9 mm wide; androecium 6.8-8.2 mm long, the longest filaments free for 1.8-2.7 mm, the connective gland-tipped, the anthers 0.55-0.75 mm long; pod obliquely triangular in profile, 2.8-3.5 mm long, the style-base latero-terminal, the prow slender but prominent, the valves hyaline in lower ½, thence thinly herbaceous, minutely gland-sprinkled, glabrous or thinly pilosulous; seed brown, ochraceous, or olivaceous, smooth, 1.7-2.3 mm long; n= 7 (Spellenberg, 1973).— Collections: 107 (vii).
Rocky hillsides, washes, and stony clay flats, often associated with scrub-oaks, junipers, or mesquite, ascending in New Mexico to 1950 m (± 6500 ft) and in trans- Pecos Texas to 2240 m (7450 ft), strongly but not obligately calciphile, widespread over central Texas n.-ward from Balcones Escarpment through the hill country to Fort Worth and Dallas, and locally to the Arbuckle and Wichita mts. in s.-centr. and s.-w. Oklahoma, w. (very abundant) over Edwards Plateau and through trans-Pecos to the Guadalupe and White mts. in s.-e. New Mexico, s. (still frequent) through detached mountain ranges of Coahuila to extreme n. Zacatecas (mpo Mazapil) and the e. piedmont of Sierra Madre Oriental in Nuevo Leon (Monterrey s. to Montemorelos), from Coahuila w. into the angle of Chihuahua below the Big Bend of Rio Bravo, and feebly w. across the Conchos valley (Julimes) to the e. foothills of Sierra Madre Occidental in centr. Chihuahua (near Cd. Chihuahua).— Flowering (May) July to November. —Representative: UNITED STATES. New Mexico: Earle & Earle 407 (NY, W); Wooton 534 (NY). Oklahoma: E. J. Palmer 44,042 (NY, UC); Waterfall 6397 (NY, OKLA); Hopkins et al. 808 (OKLA, WIS). Texas: Tracy 8333 (NY, W); Mainland & Barkley 14,519 (NY, OKLA, UC, WIS); Ripley & Barneby 13,242 (CAS, MEXU, MICH, NY, US), 13,531 (CAS, MICH, NY, US); Warnock 21,825 (NY, UC); Moore & Steyermark 3345 (NY, UC). MEXICO. Chihuahua: Pringle 658 (BR, F, M, NY, UC); Stewart 2420, 2517 (GH). Coahuila: Palmer 205, 206, both in 1880 (F, NY); Johnston 8268 (GH, TEX), 8948 (GH); Marsh 1350 (F, GH, OKLA); Ripley & Barneby 14,220 (CAS, NY, US); Ripley 14,957 (CAS, NY). Nuevo Leon: Palmer 212 in 1880 (NY); E. W. Nelson 6093 (F, NY, US). Zacatecas: Stanford, Wetherford & Northcraft 564 (ARIZ, NY).
Dalea frutescens (becoming shrubby) Gray, Boston Jour. Nat. Hist. 62 (Pl. Lindh. 2): 175. 1850. — "376...on the Guadeloupe, Sabinas, and Pierdenales. July, August. (Western Texas, Mr. Charles Wright. Monterey, N. Mexico, Dr. Edwards in Herb. Torr." — Holotypus, Lindheimer 376, collected in 1846, GH! isotypi, NY, US, W! paratypi, Wright 119, NY, OXF, US, and 1353, NY! (from Live Oak Creek and Pass of the Limpia, respectively), Edwards & Eaton in 1846, NY (herb. Torr.)! — Parosela frutescens (Gray) Rose, Contrib. U. S. Nat. Herb. 8: 303. 1905.
Parosela laxa (loose, of the flower-spike) Rydb., N. Amer. Fl. 24: 85. 1920.— "Type collected in the vicinity of Devils River [ Val Verde Co.], Texas, October 16, 1913, Rose & Fitch 17957..." — Holotypus, NY, isotypus, US! — Parosela frutescens var. laxa (Rydb.) B. L. Turner, Field & Lab. 24: 16. 1956.
A small, neatly attractive shrub, seldom more than knee-high, with crooked stems that root when decumbent and so form little thickets of rich green foliage, this disappearing in summer or early fall under a veil of rose-purple flowers. Except where it approaches, in Nuevo Leon and adjoining southeastern Coahuila, the related but taller and yellow- flowered D. hospes, it is the only dalea in its range characterized by a short-toothed calyx glossily glabrous externally but fringed around and within the orifice with short silvery hairs. Variation in D. frutescens is noticeable only in a few features and amounts to little in the context of sect. Parosela. In Texas the main cauline leaves have four to nine pairs of leaflets, and most of them five or more; south of Rio Grande there are seldom more than five pairs. Prevailingly the flower-spike is moderately compact, but varies according to number of flowers from capitate to oblong, the spikes terminal to lateral branchlets being generally shorter than that terminal to a primary axis. A loose spike, with flowers or pods spaced along the axis at intervals of 2-4 mm, is of some frequency in southcentral Texas, especially on the lower Pecos and Devils rivers. It was found first by Charles Wright (no. 120), as mentioned by Gray in Plantae Wrightianae, and is the one differential character ascribed to Parosela laxa. However, plants with subcapitate and loosely spicate inflorescences have been seen side by side in Kerr County, Texas (Barneby 13,538). and much of the material from outlying stations in the Arbuckle Mountains in Oklahoma are of the laxa type (cf. A. & R. Nelson & Goodman 5385, in part, UC). Turner (1959, p. 150, map 92) maintained for this form a D. frutescens var. laxa, but it seems hardly to deserve formal recognition. Ordinarily the spike-axis is pilosulous, but the hairs are sometimes few and short, occasionally absent. In east-central Texas the peduncles are mostly short (up to 1.5 cm) whereas in Mexico and west of the Pecos the more vigorous, central spikes are elevated on peduncles up to 1.5-4.5 cm long. In Mexico the bracts tend to be longer than in Texas, their tails longer and more tapering. In short, there are signs of incipient racial differentiation within the species, but none emerge as stabilized or geographically segregated.
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:
