Sophora japonica is widely used in landscaping, but there are often problems such as crown deviation and long cultivation time in conventional seedling raising. In view of these problems, a set of cultivation techniques of three seedlings of Sophora japonica were explored in production practice. The main points are as follows:
Grafting: grafting time: the first half of April.
1. Preparation: Select seedlings with DBH above 5cm in the nursery in spring, and leave 1.5-2.5m for dry setting (the dry setting height can also be determined according to user's requirements). When the new branches grow to about 10cm, select 6-8 branches with different directions and uniform distribution. The rest is erased from the base. The planting height of these branches on the trunk is preferably concentrated in the range of 10cm. If the number of branches is insufficient or unevenly distributed, the adjacent vacant branches can be allowed to re-core by 5cm to meet the requirements.
2. Transplanting: Transplanting with soil at the row spacing of 1.5m×2m at the end of March and the beginning of April of the following year, watering after transplanting and waiting for grafting.
Third, grafting: grafting time: the first half of April.
Scion selection: select the peripheral branches of Sophora japonica street trees with beautiful tree body and no pests and diseases. The collection of branches can be combined with the pruning of mother trees. Dormant buds are better. From late April to mid-May, dormant buds were taken as scions and grafted on new branches of Sophora japonica 1-2 years old. In addition, budding can also be carried out in early and middle July with new buds of that year.
Grafting: bud grafting. First, insert the cutter on the smooth back of the base of the rootstock branch, 5- 15cm away from the base, gradually cut up to the xylem, and finally cut out the oval joint with a length of about 2-3cm. Cut the knife at the lower part of the whole bud about 1cm in the middle of the scion, and gradually cut up to the xylem, and cut the oval bud plate about 1cm above the bud. The length and width of the bud are slightly smaller than the rootstock interface. Put the buds on the rootstock and align them on all sides. If the bud is small, one side of the bud can match the section of the rootstock. And then fully sealed and bandaged with plastic film.
4. Post-grafting management: Cut off the branches of 1/2 immediately after grafting. Leave a new branch at the front of each branch, and all the others are sparse. About 20 days after grafting, the anvil is cut at the front end of bud grafting 1cm, and the extra buds are often erased. According to the growth status of the tree, re-coring is carried out in the drooping part of the branch to increase the number of branches. Usually the heart is picked twice. Topdressing twice in mid-June and mid-July, mainly with nitrogen fertilizer, combined with topdressing and watering. Control pests and weeds in time.
Post-grafting management
After 10 days, the buds began to grow, so management should be strengthened.
(1) Irrigation: immediately after grafting, irrigate at 1 time, then keep the soil moisture frequently and replenish water in time.
(2) Unbind. From the end of April to the beginning of May, the buds on the scion have sprouted and grown into new branches. The outdoor temperature is very high. Spread out a corner of the plastic bag, gradually release the air, and then completely remove it in a few days. After a period of time, after the wound and the interface are completely healed, the bound plastic strips will be released to prevent the branches from being clamped.
(3) Remove tillers, and erase the sprouting tillers of rootstocks in time after the grafting survives, so as to ensure the normal growth of Sophora japonica scions.
(4) Straightening: the growth process of new shoots begins to grow upwards, and then droops. The upward growing part of the scion should be tied tightly with a stick to avoid being blown off by the wind.
5] Tree culture, combined with winter pruning and continuous plastic culture, promotes the formation of ideal crown.
(6) Carry out intertillage weeding and pest control in time. In spring, Sophora japonica was used as rootstock to graft Sophora japonica with high branches, and the average grafting survival rate was over 90%.