Description from
Flora of China
Iris nepalensis D. Don; I. yunnanensis H. Léveillé; Junopsis decora (Wallich) W. Schulze.
Plants densely tufted, with small growing point. Roots swollen, fusiform, tuberous. Leaves linear, 10--35(--60) cm × 2--8 mm, veins 2 or 3, base surrounded by brown fibers. Flowering stems sometimes shortly 1-branched, 10--25 cm × 2--3 mm; spathes 3, green, lanceolate, 4.5--9.5 cm, 2-flowered. Flowers violet or pale blue, 2.5--6 cm in diam. Perianth tube 2.5--3 cm; outer segments spreading, obovate, 2.5--4 × 0.8--1.8 cm, crest central, yellow, low, undulate; inner segments erect, narrowly elliptic, 2.5--4 × 0.5--1.2 cm. Stamens 1.5--2.5 cm; anthers yellowish white. Style branches 2--3.5 cm. Capsule ellipsoid to ovoid, 2--3.5 × ca. 1 cm, apex shortly pointed. Fl. Jun, fr. Jul--Aug. 2 n = 24.
White-flowered forms from Yunnan have been described as Iris decora var. leucantha X. D. Dong & Y. T. Zhao (Bull. Bot. Res., Harbin 18: 150. 1998. Much further work needs to be undertaken on the I. decora group. According to one of us (Noltie), true I. decora is a large plant probably restricted to Bhutan, Nepal, and S Xizang. The plant commonly occurring in China is much smaller and grades into I. collettii.
Grassy hillsides on plateaus, open stony pastures, cliffs; 2800--3100 m. Sichuan, Xizang, Yunnan [Bhutan, N India, Nepal].