Shrubs , evergreen, 0.5-1.5 m. Stems often ± dimorphic, with elongate primary and somewhat elongate axillary shoots. Bark of 2d-year stems brown or gray, glabrous. Bud scales 1.5-3 mm, deciduous. Spines absent. Leaves 3-foliolate; petioles 1.5-5 cm. Leaflet blades thick and rigid; surfaces abaxially ± dull, papillose, adaxially dull, rarely glossy, somewhat glaucous; terminal leaflet sessile, blade 2.9-5.4 × 2.2-3.2 cm, 1.3-2.4 times as long as wide; lateral leaflet blades ovate or rhombic to lanceolate, 1-3-veined from base, base acute to rounded-obtuse, margins plane or undulate, lobed, with 1-2 teeth 5-13 mm high tipped with spines to 2-3.4 × 0.3-0.4 mm, apex acuminate. Inflorescences racemose, rather dense, 6-11-flowered, 1.5-2.5 cm; bracteoles membranous, apex acute or obtuse. Flowers: anther filaments with distal pair of recurved lateral teeth. Berries blue-black, glaucous, spheric to short-ovoid, 5-6 mm, juicy, solid. Flowering winter (Jan-Mar). Shady spots in rocky canyons; of conservation concern; 800-1100 m; Ariz. Berberis harrisoniana is endemic to the Kofa and Ajo mountains. It has not been tested for resistance to infection by Puccinia graminis .

Plant: Shrubs 50-100 cm tall Leaves: trifoliolate, 4-9 cm long; petiole 1-4 cm long; leaflets oblong, elliptic, ovate or obovate, sessile, coriaceous, light green but usually not very glaucous, scarcely paler below, 2.5-5.0 cm long, 2.0-3.5 cm wide; veins prominent; teeth of leaflet margin 1-2(-3) pairs, triangular to attenuate, 6-20 mm long, each bearing a spine INFLORESCENCE: 2-4 cm long, corymbiform to racemose, 3-10-flowered; bracts green, acuminate, ovate to rhombic, 1.0-2.0 mm long; bracteoles 2, opposite or with one appressed to calyx and the other 2-4 mm below it, ovate to lanceolate, 1.0-1.5 mm long Flowers: sepals 9; outer sepals ovate, 1.5-2.0 mm long; middle sepals broadly ovate to lanceolate, 2.0-2.5 mm long; petals and inner sepals 6 mm long; stamens 2.5-3.0 mm long; filaments bearing 2 lateral spur-like teeth at apex Fruit: berries, globose to subglobose, black to dark blue, subglaucous, 5-6 mm long; SEEDS reddish-brown, fusiform, 3-5 mm long Misc: Mtn. canyons; 750-1050 m (2500-3500 ft); Feb-Mar REFERENCES: Laferrière, Joseph E. 2001. Berberidaceae. J. Ariz. – Nev. Acad. Sci. Volume 26(1).