The deciduous tree Eucommia ulmoides Oliv. of the family Eucommiaceae (see Figure 2-105) is used as a medicine for its bark and leaves. The whole plant, except the xylem, contains peach leaf coral glycosides and eucommia gum. The bark of the tree contains 5% to 10% of eucommia gum, the root bark 10% to 12%, the leaves 3%, and the fruit 15% to 27.5%. Eucommia gum is the second largest rubber resource in China, with a wide range of uses. The bark still contains resin, the leaves still contain kaempferol, caffeic acid, chlorogenic acid, tartaric acid and reducing sugar, etc. The seeds still contain a large number of fatty oils, mainly linoleic acid, the bark extract has hypotensive effect and diuretic effect. Taste sweet, slightly pungent, warm. It has the functions of tonifying the liver and kidney, strengthening the muscles and bones, tranquilizing the fetus and lowering blood pressure. It is mainly used for treating kidney deficiency and lumbago, lumbar and knee weakness, urinary leakage, fetal leakage and high blood pressure. Eucommia leaves contain the same active ingredients as the skin of Eucommia, and the pharmacological effects are basically the same, in addition to replacing the skin for medicinal purposes, but also can be made into health care tea for patients with high blood pressure and other long-term use, in addition, Eucommia leaves are mixed in the feed for chickens, can improve the egg production rate of laying hens. In recent times, due to the in-depth research and development of eucommia leaves and eucommia gum, the scope of application has been enlarged, and the demand for it has increased greatly, so it is very valuable for development. It is mainly produced in Sichuan, Shaanxi, Hubei, Hunan, Jiangsu, Guizhou and Yunnan provinces and autonomous regions. Many provinces and cities across the country are cultivated.

Duzhong is suitable for mild, humid climate. Its adaptability is strong, in the annual average temperature of 11.7 ~ 17.1 ℃, the average temperature in January 0.2 ~ 5.5 ℃, the average temperature in July 19.9 ~ 28.9 ℃, the absolute maximum temperature of 33.5 ~ 43.6 ℃, the absolute minimum temperature of -4.1 ~ -19.1 ℃, the annual precipitation of 478.3 ~ 1,401.5 mm of the region can be normal growth and development. Adult trees are more resistant to severe cold, and can withstand low temperatures of -22.8℃ in newly introduced areas, and the roots can withstand low temperatures of -33.7℃. Eucommia trees also require a certain low-temperature dormancy stage in winter. In the south subtropical region of China, due to the high winter temperature, it lacks the low-temperature conditions required for winter dormancy, so it is not suitable for planting in the south subtropical region.

Soil to deep, fertile, well-drained soil is better, pH value of 5.0 to 7.5 can be planted.

Figure 2-105 Morphology of Cortex Eucommiae plant

1. fruiting branches 2. male flowers 3. female flowers 4. seeds 5. bark (showing gum filaments)