The details are as follows:

1 Timely cutting and drying

Every year after the growth stops in spring and before the second growing season comes (usually in early July), Cut off the curved part of the top and send out new branches, then choose a vertical branch to be the new trunk.

2 Reasonable pruning

The so-called reasonable pruning means to retain as many side branches as possible without affecting the growth of the trunk. This is beneficial to the thickening of the trunk and accelerates lignification. process to avoid trunk bending. The specific operations are as follows:

(1) Horizontal branches and branches close to horizontal are generally not pruned and allowed to be pruned naturally.

(2) Competing branches that affect the growth of the main head should be cut off in time.

(3) Control the growth of other side branches that do not compete for growth. When their thickness reaches 1/2 of the thickness of the trunk, they should be cut off in time. Prevent the trunk from being sharpened too much and increase the height of the trunk. If the wound is cut off too late, it will be detrimental to healing.

3 Cut and dry again

For 2-3a-old seedlings, when they begin to grow in spring, if the seedlings do not have an obvious main head or have a main head but it is too skewed, it should be Cut the stem again and choose the initial deflection position.

4 Maintain a reasonable density

The diameter of small seedlings is 2cm, and 45,000 to 60,000 seedlings per hectare are left; the diameter of large seedlings is more than 4cm at breast height, and about 12,000 seedlings are left per hectare. This not only ensures photosynthetic needs, but also meets the requirements of natural pruning.

5 Other measures

Apply more phosphorus and potassium fertilizers during the seedling stage, and strengthen foliar spraying during the growing season, which will help strengthen photosynthesis, accelerate the lignification process, and prevent the trunk from bending. In short, if you want to cultivate qualified Sophora japonica seedlings, you must master three key points:

① Cut off the stems and change heads in time.

② Avoid excessive pruning.