Transplantation of large seedlings of Camellia oleifera is used to accelerate the results of afforestation and increase the income of forest farmers as soon as possible

Transplantation of large seedlings of Camellia oleifera is used to accelerate the results of afforestation and increase the income of forest farmers as soon as possible

Nie Xiaoqin

The use of oil tea seedling transplantation and afforestation is an effective measure taken by Taihu County in recent years to carry out industrial poverty alleviation work, with the purpose of reducing the management costs of poor mountainous areas, accelerating afforestation results, and increasing the income of forest farmers as soon as possible. So far, the planting area of camellia oleifera seedlings in the county has reached 2423 mu. In order to further improve the survival rate of camellia oleifera seedling afforestation and ensure that economic benefits are obtained earlier under scientific management, it is necessary to master certain seedling planting and management techniques.

1 Preparation before transplanting

1.1 Selection of afforestation sites

Camellia oleifera is a deep-rooted tree species with developed main roots, and the requirements for soil, temperature and other conditions are not strict, but the soil pH and ambient temperature and light conditions directly affect its growth and yield. Camellia oleifera prefers acidicity and is generally grown in acidic and slightly acidic soils with p-h values of 4.5 to 6.5. Although the influence of altitude, aspect and slope on the growth and development of Camellia oleifera seedlings is indirect, their changes can cause changes in temperature, humidity, light conditions and soil conditions, and the normal growth requirements for temperature are 15 °C ~ 22 °C, therefore, afforestation land generally chooses hilly land below 600 meters above sea level, deep soil (more than 80 cm) or slope below 25 ° in the middle and lower part of the mountain field, with sufficient light for afforestation. Judging from the growth of Camellia oleifera seedlings in Taihu County, the seedlings below 300 meters above sea level grow and develop the best, and the oil tea in Yangpo has a higher yield and high oil content than oleifera in Yinpo.

1.2 Drill holes in the ground

Afforestation and land preparation has the ability to improve soil moisture, nutrients and ventilation conditions, and can also affect the temperature and heat of the near surface layer, improve the survival rate of afforestation, and promote the growth and development of Camellia oleifera seedlings. Most of the afforestation of Camellia oleifera seedlings adopts burrow-like land preparation, and the plant spacing can be adjusted appropriately according to the size of the tree age, generally 3 meters × 3 meters. In order to ensure the stretching of the root system of the seedling, the colonization hole should be deepened and enlarged according to the size of the seedling and the root system, and the general requirements are 60 cm×60 cm × 60 cm. The topsoil and subsoil taken out when digging the hole should be stacked separately, and after digging the hole, each hole with conditions is fertilized 15 to 20 kg or 1 kg of cake fertilizer, and then the backfill topsoil is mixed evenly and covered with soil to avoid fertilizer loss. Organic fertilizer should be applied at least one month before planting seedlings, and after fermentation of organic fertilizer can increase soil porosity and improve soil fertility. Phosphate fertilizer can be added appropriately during colonization to facilitate the root and fruit.

2 Large seedlings are dug and transplanted

2.1 Seedling varieties and quality requirements

The selection of Camellia oleifera varieties is mainly to ensure high yield, stable yield and high quality, followed by stress resistance and other economic traits. Under the principle of adapting to local conditions, first select the local adaptability and planting adaptability are good in the local variety, to introduce the local varieties that do not exist locally or the varieties that are better in the field, the varieties identified after the experimental cultivation of national or provincial selection should be selected, and the varieties are strictly in accordance with the introduction procedures and requirements. At present, the varieties of Camellia oleifera planted in Taihu County are mainly Changlin series, including Changlin No. 4, No. 18, No. 27, No. 40, No. 53, No. 166, etc. From the perspective of the growth of Camellia oleifera in the county, the fruit yield of Changlin No. 4, No. 18 and No. 40 is better, and the oil yield of Changlin No. 166 fruit is higher. In addition to choosing good varieties suitable for local planting, large seedlings with lush foliage and no disease should also be selected for planting.

2.2 Seedling mining and transportation

In order to improve the survival rate of camellia oleifera seedlings, to ensure that there are enough absorbed roots in the soil ball is the key, the diameter of the soil ball is generally 8 to 10 times the diameter of the seedling, the height is about 2/3 of the diameter of the soil ball, while digging seedlings, the soil ball should be tied with grass rope in time, and the soil ball should be protected during the shipment of seedlings to avoid fragmentation and scattering. The best place of origin of seedlings is to choose nearby, so that the seedlings can be started at any time, planted immediately, and try to complete them in one day as much as possible to avoid the seedlings from being exposed to the sun and wind for a long time. If you really need long-distance transportation, it is best to cover it with a vehicle cover cloth, and set off the surrounding cover cloth ventilation and cooling at a certain interval, on the one hand, reduce the survival rate of seedlings due to excessive water loss due to high winds during transportation, and prevent burning seedlings due to excessive internal temperature.

2.3 Pruning of seedlings

Because it takes a certain amount of time for new roots to be issued after planting, and the roots carried are mostly coarse roots with weak absorption capacity, the root system returns to normal water absorption process is longer. In order to ensure that the moisture absorbed by the root system and the water lost by the transpiration after the planting of large seedlings can maintain a balance, the canopy must be pruned before planting, and the growth of the side branches can be promoted after pruning the main branches, so that the canopy can be restored to the original level as soon as possible. At the same time, the branches of diseases and insects and the long branches of the tree are cut off, and 1/5 to 1/8 of the branches and leaves are retained in the whole plant, which not only controls the transpiration of the large seedlings after planting, but also ensures the photosynthesis of the trees. For large cuts after trimming the trunk, it is best to wrap them with plastic film to avoid rotting of the cuts.

2.4 Planting of seedlings

Afforestation of camellia oleifera seedlings should be carried out in the evening of cloudy or sunny days from spring to sting, and the spring planting is completed before March 20, and the autumn planting begins in November, and the specific time is determined according to the weather conditions. The key to the survival of large seedlings is to have large roots, appropriate depth, and dense connection of root soil, so when planting, the depth should be moderate according to the size of the soil ball, and the depth of the cover should be the same height or slightly higher than the depth of the original rhizosphere. When covering the soil, first break the fertile soil and topsoil and fill it around the roots, then put the subsoil, when filling the soil to halfway, hold the trunk gently lift or shake, and then support the seedlings and then fill the soil, to be layered compaction, filled and piled into a steamed bun type, conditionally covered with a layer of 2 to 5 cm of straw, and then, using a thin compaction of the soil [, and finally pour enough fixed root water to ensure that the root system and the soil are tightly integrated. From the analysis of the afforestation results of camellia oleifera seedlings in Taihu County, afforestation in the barren field, in addition to excavating a certain depth of the front and back drainage main ditches, it is best to use the shallow planting method of soil pile, the plots with large winds are slightly deeper, and the plots with small winds are shallowly planted, which can prevent the seedlings from dying due to water rot.

3 Parenting management

After the planting of camellia oleifera seedlings, timely care and management are carried out to create excellent growth conditions to meet the requirements of trees for water, fertilizer, gas and light, and it is a key measure to ensure the high yield, stable yield and high quality of camellia oleifera.

3.1 Fertilizer water management

"Dry roots, wet shoots", after the planting of large seedlings, it is necessary to properly control the water. The root system of newly planted seedlings has weak water absorption ability, the demand for soil moisture is less, and the soil moisture content is too large, which destroys the breathability of the soil, affects root respiration, is not conducive to the extraction of new roots, and will lead to rotten roots or even death. Therefore, after watering the head water during planting, water appropriately when the soil is dry in the later stage, as long as the soil is moist, avoid water accumulation at the roots. After the large seedlings are planted and alive, they basically enter the early stage of fruit, and the task of care and management in this period is to protect the robust growth of the tree, strive for early harvest, and remove the flower buds of the year of planting to ensure that there are more nutrients for the normal growth and development of the seedlings. In order to increase the fertility of forest land, it can be combined with cultivation and cutting of irrigation or cutting green manure to press green in the woodland, increase soil organic fertilizer, and improve soil physical and chemical properties. In order to increase the nutrients required for tree growth, nitrogen fertilizer or compound fertilizer can be applied appropriately after planting the second year of planting to promote the expansion of new and secondary roots to the four sides. Fertilization is used for ditch application or hole application, with the trunk as the center, to the radius of 30 cm more than the average radius of the root system to dig a trench or dig a hole, the depth is not less than 60 cm, each plant is fertilized about 1 kg, and the soil is backfilled in time after fertilization, so as to avoid fertilizer evaporation and reduce fertility. After camellia oleifera enters the fruiting stage, the metabolism is strong, vegetative growth or reproductive growth is very strong, and the management of soil, water and fertilizer in this period directly affects the yield and quality. In order to improve soil conditions, under the premise of soil and water conservation, summer shoveling and winter excavation of forest land should be carried out in a timely manner. Summer is the season of vigorous growth of trees and weeds, the two compete with each other for nutrients, water, through the summer shallow hoe shoveling mountain can be timely elimination of weeds, loosen the soil, reduce water evaporation. Winter digging is generally carried out once every 3 to 4 years, the depth requirements are 20 cm to 25 cm, and the soil chunks are dug up to allow it to weather in winter, which plays a role in deepening the curing of the soil and reducing the occurrence of pests. After camellia oleifera enters the fruiting stage, the nutrients of the woodland will gradually decrease, but the forest trees need more elements, otherwise there will be "deficiency of vegetarian disease", affecting the normal growth and development of the forest trees. Therefore, rational fertilization has become an important means to improve the yield and quality of Camellia oleifera. Fertilization is mainly based on nitrogen, phosphorus and potassium fertilizer, fertilization before flowering, generally based on nitrogen fertilizer, appropriate amount of phosphorus fertilizer, can supplement the lack of nutrients in the tree body, promote flowering; topdressing after flowering, to topdress nitrogen, phosphorus fertilizer mainly with potassium fertilizer, can promote fruit expansion, prevent fruit fall. Fertilization is carried out by extending the vertical projection of the canopy on the ground to open the circular groove or hole application, and apply urea 25 kg per mu, phosphate fertilizer and 50 kg each potassium fertilizer. In addition to soil fertilization, extra-root topdressing or foliar spraying can be used.

3.2 Tree shaping

Plastic surgery is to form a tree-shaped skeleton with abundant and stable yields, but it must be maintained by pruning; pruning can adjust the relationship between growing branches and fruiting branches to ensure balance and coordination, and achieve stable yields for consecutive years. To achieve the effect of plastic pruning, it is necessary to comprehensively consider the biological characteristics of Camellia oleifera varieties, growth habits, age period, environmental conditions and management technology levels, etc., and cultivate a suitable tree shape of "tangible and undead, invisible and not chaotic" according to the plastic principle of "pruning the tree, forming with the branches", so as to achieve the purpose of premature birth, high yield and high quality. Camellia oleifera is centerless trunk shape, generally shaped as the main trunk 60 ~ 100 cm, in the trunk selection and retention growth balance, good direction, angle of about 50 °, staggered three main branches, the main branch spacing of 30 cm ~ 50 cm; in each main branch to select 2 pairs of sub-main branches, staggered distribution on the main branch, in the sub-main branch and then select the fruit branch, the formation of natural happy shape or natural garden head shape. After entering the adult stage, in addition to the need for large pruning in order to control a certain height of the tree body in order to pick, when pruning every year, as long as it is appropriately removed, overlapping branches, over-dense branches and diseased branches are reduced, so that the density is moderate and conducive to ventilation and light transmission.

3.3 Pest control

The prevention and control of pests in camellia oleifera must adhere to the principle of "prevention first", based on forestry technology, to reduce the occurrence of various diseases and insect pests. From the monitoring results of pests in Taihu County, it is found that the main pests and diseases of Camellia oleifera found in the county are oleifera anthrax, soft rot of camellia oleifera, camellia oleifera coal pollution disease, camellia oleifera ruler moth, tea tianniu, oleifera wide shield bug, camellia oleifera weevil and so on.

3.3.1 Biological control Strengthen the care and management of camellia oleifera forests through summer shoveling and winter digging, maintain appropriate density, ventilate and light in the forest, and enhance the disease resistance of camellia oleifera; combined with pruning, completely remove diseased branches, diseased leaves and diseased fruits, burn them in a concentrated manner, kill insect eggs and pupae, and reduce the source of infection, so as not to spread and spread.

3.3.2 Disease Symptoms and Chemical Prevention and Treatment Ofe tea anthrax is the main disease of camellia oleifera, fruits, branches, and leaves can be diseased, and after the occurrence of disease, it causes serious fruit fall, bud drop, branch death, and even the decline of the whole plant. Spray 1% solubility Bordeaux liquid at the onset of the disease, or 50% carbendazim wettable powder with 500 times water, or 50% dextrin special wettable powder with water 800 to 1000 times liquid for prevention and control. Soft rot of camellia oleifera mainly harms camellia sinensis, buds and fruits, mainly manifested as rotting and falling off the flesh of the leaves, and the fruit cracking and falling fruit. Spray 1% solubility Bordeaux liquid at the onset of illness, or spray with 0.8% Bordeaux liquid plus 0.5% Selissant, or spray once with 50% wet bacteriodetic 600 to 800 times liquid, or spray control with 50% carbendazim 300 to 500 times liquid. Camellia oleifera coal pollution disease occurs on the branches and leaves, causing flowers and fruits to fall after the onset of the disease, reducing the yield and quality of tea seeds, and heavy branches and leaves fall, and eventually the whole tree dies. After the occurrence of the disease, the stone sulfur compound can be sprayed in time for prevention and control, and the Baume 0.5~1°bé liquid can be used in summer and the Baume 3~5°bé liquid can be used in winter, which has a good killing effect on coal pollution diseases. For the insect pests that occur in the camellia oleifera forest, when mild, the insect trap can be trapped by hanging the insect trap during the peak period of adult feathering, and when the occurrence is more serious, in addition to the spray control using the corresponding low-toxicity pesticides, the corresponding aerosol can also be used for smoke control.

4 Conclusion

In summary, the transplantation and afforestation of camellia oleifera seedlings is one of the effective measures for the development of the forestry industry in mountainous counties. Mastering scientific cultivation and management technology, the transplanting of large seedlings of Camellia oleifera can achieve more than 95% of the afforestation survival rate, under the same conditions in the mountainous areas, the survival rate of small seedlings with 1 to 2 years old has increased by more than 2%, and at the same time, the initial management cost per mu before fruit picking can be saved by about 1500 yuan, whether it is economic benefits, ecological benefits and social benefits are very impressive.