Take out the sowing seedlings or asexual propagation seedlings from the nursery, and transplant them to continue raising seedlings. Transplanted seedlings can increase nutrient area, improve ventilation and light transmission conditions, promote the growth of lateral roots and fibrous roots, improve quality and enhance adaptability to afforestation site conditions. The key to ensure the survival of transplanted seedlings is to keep the water balance in the body. Besides keeping the soil moist, we should also protect the roots of seedlings to prevent water loss.
The main technical links are:
① Prepare.
Before transplanting, seedlings should be graded, the size should be the same, and planted in different regions, which is beneficial to tending management and reducing seedling differentiation.
② transplant season.
According to the local climatic conditions and tree species characteristics. Generally, spring is the period of transplanting all kinds of trees, and the order of transplanting all kinds of trees is determined according to the germination time. Transplanting in autumn is also feasible in warm and humid areas in autumn. Some evergreen trees can also be transplanted in rainy season.
③ Transplant density.
This depends on the growth rate of seedlings, the development characteristics of seedlings' crowns and roots, the cultivation period of seedlings, the machines and tools used, etc. Generally, conifers have smaller row spacing than broadleaf trees, and the row spacing managed by machinery is larger.
④ Transplanting method.
Transplanters can be used for transplanting. Artificial transplantation generally adopts hole planting and ditch planting. As far as seedlings are concerned, there are two kinds of transplanting: bare root transplanting and soil ball transplanting.
⑤ Tending management.
Immediately after transplanting, irrigate 1 ~ 2 times, straighten the inverted seedlings and level the transplanting area. Then, according to the growth characteristics of the seedlings, irrigation, intertillage weeding, topdressing, pest control, tillering and bud smearing are carried out. Large seedlings that have been transplanted many times should be pruned. ⑥ The seedlings leave the nursery. Keep the root system intact. In production, the root length of larger transplanted seedlings is often determined according to the thickness of rhizosphere diameter.
Watering: When planting, after watering for the first time, you should generally water for the second time every 2 ~ 3 days, and then water for the third time every 4 ~ 5 days. In the future, water according to the soil moisture, thoroughly water each time, and intertillage in time after the topsoil is dry. In addition to normal watering, in summer and high temperature season, you should always spray water on the grass rope wrapped around the tree to keep it moist.
Fertilization: In addition to basic fertilizer, topdressing should be applied during transplanting, and NPK compound fertilizer is the best. Fertilization can be carried out every 20 days and stopped in early September. Fertilization should be based on the principle of applying more to weak trees and less to strong trees. For paulownia with particularly poor growth, it can also be restored by infusion.
Pest control: Summer is a frequent season, and prevention should be carried out according to the principle of "prevention first, combining prevention with control". For some stubborn diseases (such as longicorn beetles), we should take a multi-pronged approach to prevent and control them.