Cultivation Techniques and Harvesting and Processing Methods of Sophora japonica Flower Buds

Sophora japonica Flower BudsThey are the dried flower buds of the leguminous plant Sophora japonica L. (Japanese pagoda tree), and have the functions of cooling the blood and stopping bleeding, and clearing heat and purging fire. Its dried mature fruit is called Sophora japonica fruit (Huai Jiao), which has the functions of moistening the intestines and relieving constipation, and stopping bleeding and cooling the blood.

It is mainly produced in Liaoning, Hebei, Henan, Shandong, Anhui and Jiangsu provinces, and is commonly cultivated throughout northern and southern China.

(1) Morphological characteristics: A deciduous tree, up to 25 m tall. Pinnately compound leaves alternate, with 9-15 leaflets, ovate to ovate-lanceolate, apex acute or acuminate, base broadly cuneate, grayish-white on the underside, sparsely covered with short pubescence. Panicles terminal, calyx campanulate, corolla milky white. Pods fleshy, moniliform, 2.5-6 cm long, indehiscent, seeds 1-6, reniform. Flowering period July-September, fruiting period September-October.

(2) Growth habits: Sophora japonica mostly grows in temperate zones and prefers dry and cool climatic conditions. It has the characteristics of being light-loving, fertilizer-loving, cold-resistant, wind-resistant and pollution-resistant. It is not very strict in its soil requirements, but moist, fertile, well-drained neutral sandy loam is best. Seeds are generally sown after pregermination, germinating in about 1 week, with a germination rate of 40% after 5 months of storage. In the north, Sophora japonica buds swell in late March, buds open in mid-April, leaves unfold in late April, the peak growth period is in mid-May, flower buds appear in June-July, the peak flowering period is in July-August, fruit set occurs in August-September, the fruit ripening period is September-October, leaves fall in October and winter buds form, entering the dormant period; the fruit does not fall through the winter, and during the ripening process the pods break apart in segments.

(3) Cultivation techniques

1. Site selection and land preparation: Choose sunny, fertile, loose, well-drained loam. Deep plow 60 cm, level and harrow fine, make beds 70 cm wide, apply sufficient base fertilizer, using 500 kg of decomposed organic fertilizer or 5 kg of urea per mu, and 3000-4000 kg of barnyard manure spread on the bed surface.

2. Propagation methods: Seed propagation can be used, and root-sucker division can also be used for propagation.

(1) Seed treatment: Select mature, plump seeds and first soak them in warm water at 70-80°C for 24 hours. After removing them, mix them with 2-3 times their volume of fine sand, stir well, pile them indoors, and during pregermination pay attention to frequently turning them to adjust the upper and lower temperatures to be consistent so that germination is uniform; this generally takes 7-10 days. When 25%-30% of the seeds have cracked, they can be sown.

(2) Raising seedlings: Sow in drills or in holes in spring and autumn. For the drill sowing method, use a sowing width of 10-15 cm, cover with 2-3 cm of soil, and press down after sowing, using 10-15 kg of seed per mu. For the hole sowing method, sow at a hole spacing of 10-15 cm, using 4-5 kg of seed per mu.

(3) Heeling-in and transplanting: In the north, after leaf fall in late autumn and before the soil freezes, lift the seedlings and heel them in for overwintering. Dig a heeling-in trench 1-1.2 m wide and 60-70 cm deep. The following spring, transplant at a plant-row spacing of 60 cm × 40 cm, and water after planting. For root-sucker propagation, dig up root-sucker seedlings from mature trees, open holes at a plant-row spacing of 1.8 m × 1.3 m, with 1 plant per hole; generally they can become established trees in 4-5 years.

3. Field management

(1) Seedbed management: After the seedlings emerge completely, thin them 2-3 times. In the sowing year, thin to a spacing of 10-15 cm. In May-June, apply an appropriate amount of ammonium sulfate or diluted human manure and urine as topdressing. In July-August, pay attention to weeding and loosening the soil. For each mu of nursery land, use 0.75 kg of 25% nitrofen; when applying, mix an appropriate amount of moist fine soil into the herbicide, then scatter it around the seedlings. The use of chemical herbicides gives good results and saves labor.

(2) Afforestation and maintenance: Sophora japonica is mostly used as a greening tree species for the "four sides" (roadsides, village sides, house sides and water sides). In various parts of North China it is planted for street trees, courtyard trees and environmental protection forest belts. During the period when the crown is closed, dead branches and dry forks should be pruned in time, and protection and tending should be carried out to beautify the tree shape.

4. Pest and disease control

(1) Canker disease: It occurs during the seedling stage or after transplanting when drought occurs, and damages branches and trunks. Control methods:

① Strengthen management, apply sufficient water and fertilizer, and enhance disease resistance;

② Mix lime : sulfur : salt : water at 5 : 1.5 : 2.36, mix evenly, and apply to the trunk;

③ For severely diseased seedlings, cut back the trunk in time and regrow the trunk.

(2) Sophora geometrid: It damages leaves and mostly occurs during the period of lush foliage. Control method: Spray with 1000-fold deltamethrin solution or 1000-2000-fold 50% phoxim emulsion.

(3) Aphids: They generally occur in late spring and early summer, damaging young shoots, young leaves and flower buds, with the peak period in July-August. Control method: Spray with 3000-5000-fold 2.5% deltamethrin emulsion or 800-fold 40% omethoate solution.

(4) Harvesting and processing

Harvest in summer when the flower buds form, dry promptly, and remove branches, stems and impurities to obtain the medicinal Sophora japonica flower buds.

After processing and drying, the Sophora japonica flower buds are ovate or elliptical, 2-6 mm long and about 2 mm in diameter. If rainy weather occurs, they can be dried by baking or by heated kang, with the baking temperature at about 40°C.

After autumn, when the fruit matures, harvest it, remove impurities, and process and dry it to obtain Sophora japonica fruit.