PLANT: Shrub 1-2 m tall, dense, intricately branched, thorny; branches often flexuous, yellowish, gray, or reddish to purplish black, glabrous or very sparsely puberulent; thorns slender and sharp.
LEAVES: 1-5 cm long, 3-15 mm wide, glaucous green, glabrous, oblong-spatulate or oblanceolate to broadly elliptic; apex acute or rounded; base attenuate into a short petiole, the midvein and primary lateral veins usually visible.
FLOWERS: pendulous, borne singly or in groups of 2-3 (Fig. 2G); pedicels slender, 4-16 mm long; calyx cup-shaped to campanulate, blue-glaucous, glabrous, 5-8 mm long, 5-lobed, the lobes lanceolate to ovate or elliptic, equalling or exceeding the tube in length, their margins sometimes sparsely pubescent; corollatube elongate-funnel form, 12-25 mm long, expanded conspicuously at the top, from white to lavender purple, most commonly greenish with purple veins, the 5 lobes oval or rhombic, 1/5 to 1/3 the length of the tube, their margins commonly remotely ciliolate; stamens exserted; filaments adnate to a little below the middle of the corolla-tube, the free base of the filaments and the adjacent corolla-tube pilose, or the filaments densely hairy nearly to top of corolla-tube; style varying in length from about equal to stamens to surpassing them.
FRUITS: red or reddish blue due to glaucescence, ovoid, about 1 cm or slightly less in diameter, 4-50-seeded. n = 12.
NOTES: Desert grassland, riparian areas, chaparral, pinyon-juniper woodland: all cos. except La Paz, Maricopa, Santa Cruz, Yuma (Fig. 1G); 800-2250 m (2500-7400 ft); Mar-Jun, occasionally at other times; CA to TX, n to UT and CO; Coah., N.L., S.L.P., Mex.
REFERENCES: Windham, M.D. And G. Yatskievych. 2009. Vascular Plants of Arizona: Isoëtaceae. CANOTIA 5 (1): 27-29, 2009.
Common Name: pale desert-thorn
Duration: Perennial
Nativity: Native
Lifeform: Shrub
General: Spreading, thorny, intricately branched shrub, 1-2 m tall; branches glabrous to sparsely pubescent, somewhat flexuous; bark yellowish, gray, or red to dark purple; spines 5-10 mm long, slender and sharp.
Leaves: Alternate in small clusters, on short perioles; blades ovate to oblong-spatulate, 3-15 mm wide by 1-4 cm long, apex acute or sometimes rounded, base tapering, surfaces glaucous, and glabrous or nearly so.
Flowers: Pendulous on slender pedicels 6-12 mm long, solitary or in groups of 2-3 at the leaf clusters; calyx shallowly bell-shaped, 5-8 mm long, topped with 5 ovate to lanceolate lobes, these glabrous and blue-glaucous, 3-5 mm long, equaling or exceeding the length of the calyx tube; corolla greenish and tinged with purple veins, the tube narrowly funnel-shaped, 12-20 mm long, 5-6 mm broad at throat, glabrous, topped with 5 oval to rhombic lobes, these 3-6 mm long with sparsely ciliolate margins; stamens exserted, the filaments fused to the corolla tube almost halfway up the tube, pilose on the filament and corolla where fused.
Fruits: Berry ovoid, bright red and sometimes also blue-tinged due to glaucescence, 8-10 mm in diameter, with 4-50 seeds.
Ecology: Found on sand or rocky soil in a variety of community types, from 2,500-7,500 ft (762-2286 m); flowers March-June, occasionally at other times.
Distribution: s CA, s NV, s UT, AZ, s CO, NM, s TX; south to n MEX.
Notes: L. pallidum is the common Lycium of the middle and higher elevations, found throughout AZ and NM where the elevation exceeds 3,000 ft. Distinguished as being a thorny, spreading shrub with a zig-zagging branching pattern; broad pale-green leaves (hence pallida); a calyx with a rounded base and lobes as long as the tube; and a relatively large (1.5- 2 cm long), greenish-white, funnel-shaped corolla. Look also for the blue-white waxy coating ("glaucous") on the herbage. Similar to L. parishii but that species has smaller 1 cm flowers and glandular-pubescent leaves. L. torreyi is similar due to its largish flowers and light green leaves, but that species lacks a waxy glaucous coating on its herbage; has tiny 1 mm calyx lobes; and corolla lobes with visibly ciliate margins.
Ethnobotany: Considered to be a sacred plant and used ceremonially; used medicinally as an emetic and to treat toothaches and chicken pox; the berries were eaten raw, made into a drink, dried, made into jam and syrup, and boiled with stew and other foods. This is perhaps the most bitter of the Lycium fruits.
Etymology: Lycium is from Greek name Lykion, used to describe a thorny tree or shrub; pallidum means ashen, pale.
Synonyms: None
Editor: SBuckley 2010, FSCoburn 2015, AHazelton 2016
