21. Sorbus scalaris Koehne in Sargent, Pl. Wilson. 1: 462. 1913.
梯叶花楸 ti ye hua qiu
Pyrus scalaris (Koehne) Bean; Sorbus foliolosa (Wallich) Spach var. pluripinnata C. K. Schneider; S. pluripinnata (C. K. Schneider) Koehne.
Shrubs or small trees, 3–7 m tall. Branchlets blackish gray when old, terete, gray or brown pubescent when young, subglabrous when old; buds ovoid, 7–9 × 4–7 mm, apex obtuse; scales several, brownish, with grayish white hairs. Leaves imparipinnate, together with rachis 10–18 cm; petiole 1–2.5 cm; stipules persistent, suborbicular or ovate, 0.7–1.4 cm in diam., margin coarsely serrate; rachis purplish, abaxially white tomentose, adaxially sulcate; leaflet blades (8–)10–14 pairs, terminal and basal ones smaller, at intervals of 8–10 mm, oblong or nearly broadly linear, 2–3(–4) × 0.6–1.4 cm, abaxially gray tomentose and papillose, adaxially glabrous, base rounded or obliquely so, margin minutely sharply serrate near apex, with 2–8 teeth per side, apex obtuse or acute. Inflorescences terminal, 6–10 × 7–12 cm, many flowered; rachis and pedicels gray or grayish white tomentose, glabrescent, subglabrous in fruit, with prominent lenticels. Flowers 6–8 mm in diam. Hypanthium campanulate, glabrous or slightly tomentose near base. Sepals triangular, 1–2 mm, glabrous, apex obtuse. Petals white, ovate or suborbicular, 2.5–3.5 mm, glabrous, apex obtuse. Stamens ca. 20, nearly as long as petals. Styles 3 or 4, not exceeding stamens, densely pubescent basally. Fruit red, ovoid-globose, 5–6 mm in diam.; sepals persistent. Fl. May–Jun, fr. Aug–Sep. 2n = 34*.
Mixed forests on mountain slopes; 1600--3000 m. W Sichuan, Yunnan.