Sophora japonica, native to China, blooms from June to July and bears fruit from August to 65438+1October. Sophora japonica is native to North America, and it blooms from April to May every year. The flowering period is generally around 10- 15 days. Originated in northern China, especially the Loess Plateau, Northeast China and North China Plain, it is widely cultivated in northern and southern China. Japan, Korea and Vietnam are also distributed.
Sophora japonica has good ornamental value. As soon as the flowering period arrives, clusters of white Sophora japonica flowers are covered with branches, and the air is filled with a faint elegant fragrance, which is refreshing. China's ancient poems related to Sophora japonica, such as: "Autumn is full with many autumn flowers" (Autumn by Bai Juyi), "Wind dancing Sophora japonica falls into the imperial ditch, and Nanshan enters the city in autumn" (Early Autumn in Chang 'an by Zilan).
These poems eulogize Sophora japonica, a native tree species in China, rather than Robinia pseudoacacia or Robinia pseudoacacia, because Sophora japonica was introduced to China from North America in the second half of the19th century, so this problem must be analyzed clearly.
Sophora japonica is a temperate tree species, which likes light and dry and cold climate, but it can also grow in South China with high temperature and high humidity. Deep well-drained soil, calcareous soil, neutral soil and acidic soil can all grow, but they can't grow well in dry and barren low-lying areas. Resistant to dust and adapt to urban environment. Deep roots, weak germination, medium growth and long life.
Sowing and branching of Sophora japonica;
Sowing can be used for propagation, and tillering can also be used for ramet propagation.
(1) seed treatment: firstly, select mature and full seeds, soak them in warm water at 70-80℃ for 24 hours, then take them out and mix them with 2-3 times of fine sand, and pile them indoors. When accelerating germination, pay attention to frequently turning over and adjusting the upper and lower temperatures to make germination orderly, which generally takes 7- 10 days until the seeds crack by 25%-30%.
(2) Seedling raising: drill sowing or hole sowing in spring and autumn, with sowing width 10- 15cm, covering with soil for 2-3cm, pressing after sowing, and sowing amount per mu10-15 kg; Hole-sowing method, hole spacing10-15cm, and seed dosage of 4-5kg per mu.
(3) Root-retaining and transplanting: in the north, after defoliation in late autumn and before soil freezing, root-retaining and wintering are carried out, and root ditches are dug, with the width of 1- 1.2m and the depth of 60-70cm. In the spring of the following year, plant with a row spacing of 60cm× 40cm, and water it after planting. During tillering propagation, the roots and tillers of adult trees can be dug, and holes can be made at the spacing of 1.8m× 1.3m, and each hole can grow in 4-5 years.