Key Points of High-Yield and High-Quality Cultivation Techniques for Eucommia ulmoides
Eucommia ulmoides is a plant of the Eucommiaceae family and a medicinal material endemic to China. Its bark is used as medicine and has functions such as tonifying the liver and kidneys, strengthening the bones and muscles, and lowering blood pressure. Its high-yield and high-quality cultivation techniques are as follows:
1. Site selection and land preparation
Choose neutral loam or sandy loam with a sunny slope, fertile soil, and good drainage. Before planting, apply sufficient base fertilizer and plow deeply and harrow finely.
2. Seedling raising
2.1 Mother tree selection and seed treatment
When collecting seeds, choose trees over 15 years old growing in fertile soil on a sunny slope as mother trees, and collect plump seeds matured in the current year. Soak the seeds in 60°C water, allow the water to cool naturally, maintain at 20°C, and soak for 2—3 days. When the seeds swell and the seed coat softens, take them out, mix in plant ash and dry soil, mix evenly, and sow.
2.2 Sowing
North of the Qinhuai line and in subtropical high mountain areas, sow Eucommia ulmoides in 2—3 month; south of the Qinhuai line, sow immediately after collection, by drilling, with a row spacing of 23—26 cm and a depth of 3 cm, using 4—5 kg of seeds per mu. After sowing, cover with straw curtains and water thoroughly.
2.3 Nursery management
In addition to conventional measures, nursery management should especially pay attention to maintaining soil moisture, thinning and filling seedlings in time, and irrigating during high temperature and drought.
3. Transplanting
Transplanting is carried out in spring. The transplanting site should be thoroughly plowed, and pits with a diameter of about 70 cm and a depth of 70 cm should be dug. Apply high-quality farmyard manure into the pits, with a fertilization rate of 1000—1500 kg per mu, with a plant and row spacing of 1.50 m×2 m. Select disease-free seedlings about 100 cm tall, and transplant while lifting the seedlings.
4. Field management
4.1 Cultivation and weeding
In the year of transplanting, generally cultivate 3—4 times; afterward, the number can be appropriately reduced. Remove field weeds in combination with cultivation.
4.2 Topdressing
Apply farmyard manure once each before sprouting in spring and after leaf fall every year, and apply 2000—2500 kg of high-quality stable manure per mu as topdressing.
4.3 Irrigation
The number of irrigations should be determined according to local climatic conditions. In areas with precipitation greater than 600 mm, irrigation may not be needed in normal years. In areas with precipitation less than 600 mm, irrigate 3—4 times: once each before sprouting, during new shoot growth, and during the dormant period, and once 3—5 days before bark peeling. Irrigation should be carried out in combination with topdressing.
4.4 Disease control
The main diseases of Eucommia ulmoides are damping-off, leaf blight, and root rot. For damping-off and leaf blight, spray 65% zineb wettable powder at 500-600 times dilution at the early stage of disease onset, once every 25 days. For root rot, use 70% thiophanate-methyl wettable powder, dig 3—5 ring-shaped ditches 30-45 cm wide and 50—70 cm deep, 100—150 g per plant, and apply into the outer periphery of the tree crown.
5. Harvesting and processing
5.1 Harvesting
Eucommia ulmoides can only begin to be peeled after more than 10—15 years of planting, and peeling is carried out in 4—6 month. Use a saw to make a ring-shaped cut level with the ground, reaching the xylem, and make a second ring-shaped cut upward at an interval of 80 cm. Make a longitudinal cut between the two ring-shaped cuts, and gently peel along the longitudinal cut with a bamboo blade so that the bark separates from the xylem.
5.2 Processing
After peeling off the bark, scald it with boiling water, then stack it tightly and evenly flat on level ground with a wheat straw mat underneath, cover with wooden boards, press down with heavy objects, and tightly surround it with straw to let it sweat. After about 7 days, when the inner bark turns dark purplish brown, take it out, sun-dry it, and scrape off the coarse bark.