2. Morus microphylla Buckley, Proc. Acad. Nat. Sci. Philadelphia. 1862: 8. 1863.
Mountain mulberry, littleleaf mulberry, Texas mulberry
Shrubs or trees , to 7.5 m. Bark gray, fissured, scaly. Branchlets greenish, pubescent; lenticels light colored, elliptic, prominent. Buds ovoid, slightly compressed, 3-4 mm, apex acute; outer scales dark brown, pubescent and minutely ciliate; leaf scars half round to irregularly circular, bundle scars numerous, in circle. Leaves: stipules linear-lanceolate, 3-5 mm, papery, pubescent; petiole 0.3-0.6(-1.5) cm, pubescent. Leaf blade ovate, sometimes 3-5-lobed, 2-7(-9) × 1-4(-7) cm, base rounded to nearly cordate, margins serrate or crenate-serrate, apex acute to acuminate; surfaces abaxially harshly scabrous or pubescent, somewhat paler than adaxial surface, adaxially harshly scabrous. Catkins: staminate, 1-2 cm; pistillate, 8-12 × 5-7 mm, peduncle 3-7 mm, pubescent. Flowers: staminate and pistillate on different plants. Staminate flowers: calyx lobes green to reddish, rounded, hairy; stamens 4; filiments filiform. Pistillate flowers: ovary dark green, broadly ovoid, slightly compressed, 1.5-2 × 1 mm, glabrous; style branches divergent, whitish, sessile, ca. 1.5 mm; stigma papillate. Syncarps red, purple, or black, short-cylindric, 1-1.5 cm; achenes yellowish, oval, flattened, ca. 2 mm, smooth.
Flowering spring. In canyons on limestone and igneous slopes, usually along streams; 200-2200 m; Ariz., N.Mex., Okla., Tex.; Mexico.