Cultivation and Management of Robinia pseudoacacia

I. Propagation methods

Sophora japonica is easy to reproduce, root-burying, cutting, grafting, or root-digging propagation. The main and lateral roots of 1-year-old and 2-year-old Sophora japonica were selected for root-burying propagation, and the suitable diameter was 0.3-1.5 cm. 1012kg per mu of roots are needed, and 300kg / kg of roots can be cut 400 segments. Two methods of transplanting seedlings in greenhouse and burying roots in field can be selected. The indoor seedling was raised in different areas and the seedling raising time was different, so it was transplanted into the field in the middle of May. Burying roots in the field was carried out when the lowest outdoor temperature was more than 10 ℃. The roots of Sophora japonica were cut into 5 cm and 6 cm in length, and the roots were buried in the border bed by flat burying method. The bed is 1.1 meters wide, each bed is planted in 2 rows, the buried depth is about 5 cm, and the row spacing is 30 cm × 60 cm. After emergence, strengthen the management of water and fertilizer, use diammonium phosphate to potash fertilizer, the proportion is 2 ∶ 1, the dosage is 1520kg per mu.

One way to dig roots is to keep the tree motionless and dig roots around; the other is to dig out the tree with its roots together. After leaving the roots 15 to 20 centimeters, all the rest are cut off and stored with scissors. The roots should be stored immediately after they are dug up and sold with them to prevent air-drying and dehydration. Select the sandy loam soil with leeward, light shelter and soil layer thickness of 1.8m to 2m, dig the pit where there is no stagnant water, and bury the seed root and fine sand. Fine sand should be screened in advance, the stones should be removed, and a certain degree of humidity should be maintained, but the moisture should not be too large. After all the burial, add 20cm to 30cm of fine sand to protect against cold. If there is abnormal cold weather, you can add a layer of grass curtain, at the same time to prevent covering heat. The biggest problem with storage is that it can't get hot and mildew.

The seedling of Robinia pseudoacacia is easy to raise and the planting survival rate is high. The survival rate of seedlings is about 95%, the survival rate of roots is more than 80%, and the survival rate of cuttings is relatively low, which can reach 40% if cultivated properly.

II. Cultivation and management of seedlings

The row spacing is 60 cm × 70 cm, and 1000 seedlings are planted per mu. The transplanting of Sophora japonica should be carried out after falling leaves in autumn or before sprouting in spring. The planting time is determined according to the regional temperature conditions, the lowest temperature in spring is 10 ℃, and it can also be transplanted after Frosts Descent in autumn. Transplanting seedlings in 2012 requires 40 cm in length, width and depth, and large seedlings should be appropriately enlarged. The bottom of the hole was fertilized with diazepam phosphate potassium fertilizer, the ratio was 2 ∶ 1. The soil layer should be isolated by 15cm to 20cm. Pour the saplings with water and fill the soil until the water seeps down. Timely watering in arid areas to keep the soil moist.

The lateral center of the seedling is removed before it grows to 3 cm to ensure the rapid growth of the trunk. 1.8 meters of the trunk began to leave side branches, and when the trunk grew to 2.5 meters, the heart of the trunk tree was removed to meet the needs of greening street trees. Timely fertilization and weeding to prevent the occurrence of diseases and insect pests.