Phoebe bournei is a shade-tolerant tree species, which generally grows in places with relatively fertile soil and humid climate, especially in the lower part of shady slopes of hillsides, valleys and gullies, loose soil layers along rivers and other soils with good drainage and strong acidity. Nanmu has deep roots and can withstand short-term flooding. Young Phoebe bournei trees have well-developed terminal buds, straight trunks, short lateral branches, a pointed crown and obvious advantages at the top. In the prime of life, the growth rate of Phoebe bournei gradually slowed down, the lateral branches expanded, and the crown gradually changed from a steeple to a bell shape.

Phoebe bournei is an evergreen tree with a straight trunk. Its bark has three colors: white, brown and gray. Phoebe bournei leaves are leathery, generally in the form of inverted needle, inverted ellipse and narrow ellipse. The leaves are slightly convex below and slightly concave above, with feathers. Phoebe bournei often blooms in April, with yellow flowers, ripe fruit 10 ~ 12, oval nucleus and black.

2 Nanmu nursery selection and establishment

2. 1 Nanmu nursery selection

Generally, in the process of establishing nanmu nursery, areas with loose and deep soil layer, neutral or acidic soil, fertile soil, abundant water, convenient irrigation and drainage of tree species, warm and sunny, convenient transportation and far away from people, livestock and pollution sources will be selected as nursery land, and the soil properties are generally sand or clay. Because nanmu is mainly used for urban greening construction, it is best to set the nursery in an area where it can be supplied centrally, which is also convenient for relevant staff to carry out centralized management. In the selection of nursery land, it is generally arranged reasonably according to the demand of nanmu in the city and the urban area. Generally speaking, the total area of urban garden nurseries should account for about 2% of the urban area, so as to meet the basic requirements of urban greening seedlings and achieve good overall results.

2.2 the establishment of nanmu nursery

2.2. 1 road construction

Usually, in the process of road construction, the location of main roads should be determined according to the total area of nursery and the area of central nursery area. After the location of the main road is determined, the center line of the main road is taken as the baseline of the nursery road system, and then the next road construction work is carried out. In addition, when building roads, the position of drainage ditch must be reasonable, laying a good foundation for the smooth drainage of nanmu cultivation nursery in the later period.

2.2.2 Land consolidation

Because the construction cost of Nanmu nursery is high, in order to reduce the construction investment as much as possible, the selected area must be developed and utilized more reasonably, and technicians and staff should develop and level the land according to the specific conditions of the construction area and terrain. In the process of land leveling, we should try our best to protect the original soil layer in this area from being destroyed and create a healthier and better soil environment for the growth of Phoebe bournei seedlings. In addition, if the slope in some places is too large, it is best to build terraces to prevent soil erosion. After these reasonable arrangements, the land will continue to level off.

3 planting and cultivation of Phoebe bournei seeds

3. 1 treatment of Phoebe bournei seeds

The quality characteristics of Phoebe bournei seeds will directly affect the growth of seedlings, so we should pay full attention to them in the process of seed selection. When harvesting, try to choose mature seeds on the mother tree that are healthy and free from pests and diseases, so as to ensure that the collected seeds are full and pure. If the seeds are stored for too long and are not sown after harvest, the quality and germination rate of Phoebe bournei will be affected to some extent, so the seeds must be treated in time after harvest. The usual treatment method is to take out the seeds by rolling, kneading, beating, wind, drying, etc., and then remove all kinds of impurities and residual branches and leaves.

3.2 Phoebe bournei seeds promote leaf buds

Because it takes a long time for seeds to germinate under natural conditions, in order to meet the market demand and make the seeds germinate as soon as possible/shorten the time required for germination as much as possible, seeds can be artificially germinated, that is, suitable conditions can be created to germinate the seeds of Phoebe bournei as soon as possible, thus improving the germination efficiency of Phoebe bournei seeds and further achieving the purpose of orderly emergence and robust growth of Phoebe bournei seeds. Phoebe bournei seeds have the characteristics of short dormancy period, hard shell and oily, so when treating seeds, they can be soaked in hot water near 100℃, then stirred, naturally cooled, soaked for 24 hours after cooling, fished out and dried on a flat net for later use.

4 Selection of sowing method and sowing time

4. 1 Selection of sowing methods

The general sowing method of Phoebe bournei is hole sowing, that is, the seeds of Phoebe bournei are dug according to a certain spacing. In order to ensure the survival number of Phoebe bournei seeds, two germinated seeds are usually put in each dug hole.

4.2 Selection of sowing time

Generally, the choice of sowing time is related to the local environment and climate, and then the specific sowing time is determined by combining the time when Nanmu leaves the nursery, which is usually February-March every year.

5 Late management of sowing and seedling raising in greenhouse

Management after sowing, as the most important part of seedling raising, often directly affects the effect of seedling raising. Therefore, in order to cultivate more high-quality seedlings, it is necessary not only to sow correctly and reasonably, but also to do well the management after sowing. Therefore, it is necessary to carefully manage nanmu seedlings before and after they are unearthed, so as to lay a reliable foundation for the healthy growth and development of later seeds.

5. 1 intercropping

Because the seedlings are prone to grow too densely and crowded in the seedling stage, it is necessary to observe the growth of seedlings frequently, and once the crowded situation is found, it is necessary to space the seedlings in time.

5.2 replanting

In the process of seedling growth, due to various unfavorable factors, seedling death is inevitable. Therefore, after watering the seedlings at night, replanting should be carried out according to the seedling spacing.

5.3 coverage rate

In order to prevent soil hardening and water loss, Phoebe bournei seedlings are often covered with straw and plastic arch shed after sowing, which can not only keep soil moisture, but also prevent seedlings from being hit by direct sunlight and wind and rain, and also prevent bird damage and cold wave damage to seedlings. However, when the weather becomes hot, the plastic film should be removed in time to ensure the vigorous growth of seedlings.

5.4 shadows

When the soil surface temperature is too high, the roots of seedlings are easily affected, so in order to reduce the temperature, the seedlings should be protected by shading. The light transmittance of the shading shed is preferably set to 30%. In addition, it should be noted that the movable shade shed is suitable for shade shed, which can ensure its flexibility. Shading treatment should be carried out when the soil temperature is too high, but it is not necessary to shade in sunny morning and evening and cloudy day, which is convenient for moving and removing in time.

6. Prevention and control methods of pests and diseases in greenhouse seedling cultivation

6. 1 Agricultural governance

Germs and pollutants carried by seeds are prone to diseases and insect pests during seedling growth. Therefore, seedlings must be disinfected regularly. One or two days before sowing, the seeds can be soaked in 0. 15% formalin solution 15 ~ 30 min, then the seeds are taken out, sealed for 2 hours, and finally dried to sow.

6.2 chemical treatment

In general, omethoate is used to control pests that may occur in the early stage of seedlings, and carbendazim bactericide is used to control diseases that may occur in the early stage of seedlings.