Ehretia corylifolia (Dian Houpo)
Ehretia corylifolia (commonly known as Dian Houpo厚朴) is a member of the family Ehretiaceae and the genus Ehretia. It can be a shrub or a tree. The tree has brown-gray bark, brown young branches with lenticels, and green, hairy young shoots. The leaves are thick and papery, ranging from ovate to elliptical. The flowers are densely arranged in terminal panicles, and the fruits are nearly spherical, elliptical, or ovoid. The flowering and fruiting period is from April to September. It grows at altitudes of 800–3000 meters in forest understories, shrublands, forest edges, and along roadsides.
Morphological Characteristics
- Growth Form: Shrub or tree, 2–18 meters tall.
- Bark: Brown-gray; young branches are brown with lenticels; young shoots are green and hairy.
- Leaves: Thick and papery; ovate to elliptical, 7–18 cm long and 4–12 cm wide; tip acute or gradually acuminate, base often heart-shaped, occasionally rounded or slightly blunt; margin serrated; green on top with coarse, appressed hairs, and pale green underneath with dense, soft, and curved hairs; the first-order lateral veins 6–8 pairs, and the central vein raised on the underside, second and third-order veins prominent and reticulate.
- Inflorescence: Terminal panicles, 4–9 cm long and 5–8 cm wide, densely hairy; flowers numerous and dense; pedicels 1–1.5 mm long, hairy; calyx 3–4 mm long, deeply 5-lobed, lobes lanceolate, 2–3 mm long, hairy on the outside; corolla white, occasionally pale yellow or pink, 9–12 mm long, 5-lobed, narrowly ovate or nearly triangular, about 3 mm long, usually recurved or folded, with fine hairs on the outer surface, cylindrical tube, expanding upward; stamens cylindrical, gradually narrowing, 4–5 mm long, inserted 4 mm above the base of the tube; anthers ovate, 1–1.5 mm long; ovary small; style cylindrical, 7–8 mm long, sparsely covered with appressed fine hairs, bifid at the tip, stigma brown.
- Fruit: Nearly spherical, elliptical, or ovoid, 5–7 mm long, green turning yellow to orange, smooth surface, splitting into two nuts each containing two seeds when mature.
Growth Environment
Grows at altitudes of 800–3000 meters in forest understories, shrublands, forest edges, and along roadsides.
Distribution
Found in Yunnan (northwest, central, and west Yunnan), Sichuan, and Guizhou.
Main Uses
- Bark: Can be used to make paper; in traditional Yunnan medicine, it replaces Houttuynia cordata.
- Leaves and Fruits: Edible; leaves can be used as pig feed.
- Wood: Suitable for construction, furniture, and shipbuilding.
Physiological Characteristics
- Dry Bark: Cylindrical or double cylindrical, 30–875 px long, 0.2–17.5 px thick, known as “cylinder bark”; near the root, the dry bark expands into a trumpet shape, 13–625 px long, 0.3–20 px thick, known as “boot cylinder bark”. The outer surface is gray-brown or grayish-brown, rough, sometimes scaly, and tends to peel off easily, with distinct oval lenticels and longitudinal wrinkles; scraped rough bark reveals yellow-brown color. The inner surface is purple-brown or deep purple-brown, relatively smooth with fine longitudinal lines, and shows an oily streak when scratched. It is hard, not easily broken, with a granular fracture surface, outer layer gray-brown, inner layer purple-brown or brown, with oiliness, and sometimes small bright stars visible. The smell is fragrant, with a spicy and slightly bitter taste.
- Root Bark (Root Houpo): Single cylindrical or irregular chunks; some curved like chicken intestines, known as “chicken intestine bark”. Hard, relatively easy to break, with a fibrous fracture surface.
- Branch Bark (Branch Houpo): Single cylindrical, 10–500 px long, 0.1–5 px thick. Brittle, easily broken, with a fibrous fracture surface.
