Abstract: Pinus tabulaeformis is widely distributed and is one of the important afforestation trees in northern China. Pinus tabulaeformis has strong adaptability, developed root system, magnificent tree posture and lush foliage, and has good functions of soil and water conservation and beautifying the environment. Chinese working people have a long history of cultivating Chinese pine. In order to ensure the survival of trees and promote the growth of fibrous roots of trees, Pinus tabulaeformis is often treated in advance by means of multiple transplanting, pre-cutting roots and root girdling. Before the tree is erected, the rubble, rubble and shrubs within 2-3m around the trunk should be removed, and the tree should be supported with three pillars to prevent the lodging from causing industrial accidents and damaging the trees. When transplanting large trees in batches, the trees should be numbered and oriented, and the north-south direction should be marked on the trunk, so that the original orientation can be maintained after transplantation to meet the demand for shade and sunshine.

Keywords: Pinus tabulaeformis transplantation technology and methods

I. Preparations

1. Selection of trees: Young and strong trees with vigorous growth and rising growth should be selected, and trees with too fast growth and low lignification should not be selected. When selecting trees in the forest, pay attention to choose trees with good dry shape and no pests and diseases, and try to be close to the trees on the gentle slope of the highway to prevent the soil ball from tilting too much, which is not conducive to planting.

2. Cutting off roots and shrinking blocks: Because the root width is large, most of the absorption roots at the base of the trunk die by centrifugation, and many absorption roots cannot be taken away with the clods during transplantation, which will cause metabolic imbalance between the aboveground and underground parts of the tree and lead to the failure of transplantation. Therefore, where conditions permit, measures can be taken one year or even several years in advance to cut off and contract the roots of the selected trees, so as to promote the generation of a large number of absorbed roots in the soil ball and improve the survival rate of tree transplantation.

2. Selection of transplanting time:

Transplanting of Pinus tabulaeformis can be carried out in spring, summer and autumn, but autumn is the best, because the growth of upper branches and leaves on the tree slows down and transpiration weakens in autumn, while the root growth can last about 1 month. At this time, after transplanting, the root system will grow again after 1 month, and some new roots can grow. When the branches and leaves of the tree began to transpiration in the next spring, the newly grown roots could already absorb water from the soil, thus improving transplantation.

Three, seedling packaging and transportation:

1. Digging seedlings: After selecting trees, determine the size of soil balls according to the diameter of 7- 10 times of the DBH of the trees, and the soil balls are "apple-shaped" with digging seedlings. When encountering a large lateral root, cut it off with a branch scissors or a hand saw, and never cut it with a shovel to avoid shaking the soil ball.

2. Ball wrapping: In addition to transplanting thick trees, large soil balls need to be wrapped with wooden boards, which can generally be tied with straw ropes. When choosing a straw rope, it should generally be thicker than the index finger. After full soaking, the soil ball should be firmly tied and extended to the trunk for a period of time to keep the trunk moist and avoid damaging the epidermis of the trunk when planting trees.

3. Transportation: When the trees are placed obliquely during transportation, they should be supported on the transportation vehicle to prevent the lower branches from breaking, and the contact between the support and the trunk should be tied with straw ropes to protect the trunk.

Fourth, planting:

Tree transplantation should be carried out simultaneously with lifting, transportation, planting and watering.

1, and the diameter of planting hole is larger than that of soil ball 1. 2 to 1. It is 3 times as deep as the subsoil 10- 15 cm, which is beneficial to the adjustment of plant trunk and the growth of root system. The planting depth is slightly deeper than the original 2-3 cm.

2, adjust the orientation of the trees, at the same time, considering that the best side of the tree posture faces the viewing surface, we should fully consider that the original sunny side of the trees continues to face the sunny side to prevent the trunk under the shade from being burned because of the opposite direction.

3. After the trunk is planted, make a triangular bracket with poles to fix the trees. The contact between the bracket and the trunk should be tied tightly with straw rope to prevent the trunk from being damaged by wind and shaking friction.

4. Water once immediately after planting, and then spray water mist to moisturize according to weather conditions. After watering, it can be covered with plastic film, which is in the shape of inverted pot bottom, which can not only improve the ground temperature, but also prevent excess rainwater from flowing into the planting hole and causing root rot.

V. Drug use:

1. In order to promote rooting, 0 can be applied to the root system. 00 1% auxin.

2, in the process of digging seedlings and lifting damaged trunk, to repair the wound, and to repair the wound.

3. Before planting, use 70% beta-cypermethrin or 40% phoxim emulsion to completely prevent insects in the canopy, and spray the bracket and trunk again after loading.

Six, the late management of trees

Careful maintenance of Pinus tabulaeformis after transplantation is one of the important links to ensure the survival of transplantation and the healthy growth of trees, which can not be ignored.

1. To support the trunk, the three-column supporting and fixing method is generally adopted to firmly support the trees and ensure the stability of Chinese pine. Generally, after one year, the roots of Chinese pine can be removed.

2. Water and fertilizer management: After transplanting Pinus tabulaeformis, water it once immediately to ensure the close combination of root system and soil and promote the development of root system, and then water it three times continuously. After watering, seal the tree tray with fine soil or cover it with plastic film in time to keep moisture and prevent the topsoil from cracking and air drying. We should master the principle of "no watering, no watering, no watering". In summer, more water should be sprayed on the ground and the canopy to increase the ambient temperature and reduce transpiration. Because of the great harm, fertilization cannot be applied in the first year, and farmyard manure should be applied in the second year according to the growth situation.

3. Auxin treatment: In order to promote new roots, 200mg/T naphthalene acid or ABT rooting powder can be added with water to promote the rapid development of roots in the early stage.

4. Wrap the trunk. In order to keep the humidity of the trunk and reduce the evaporation of bark water, the soaked straw rope can be tightly wound from the base of the trunk to the top of the trunk, and then the prepared clay paste can be applied.

Seven, cold measures

The northern part of China is cold in winter, windy and dry in spring, and the temperature changes dramatically, which is very harmful to Pinus tabulaeformis seedlings. In order to ensure the safe overwintering of Pinus tabulaeformis seedlings and avoid the death of Pinus tabulaeformis seedlings due to frost and physiological drought, effective cold protection measures should be taken, especially for some evergreen trees, newly introduced southern trees and some seedlings with weak cold resistance. The cold protection of Pinus tabulaeformis seedlings is mainly to prevent freezing injury, freezing pull-out and physiological drought, and its specific measures are as follows: covering soil for cold protection: covering soil for cold protection refers to burying overwintering Pinus tabulaeformis seedlings in the soil all winter, so that the soil of Pinus tabulaeformis seedlings and seedbeds can maintain a certain temperature, which is not affected by the rapid change of temperature and other external unfavorable factors. At the same time, it can reduce water transpiration and soil water evaporation of Pinus tabulaeformis seedlings, maintain a certain amount of soil water, help maintain water balance in seedlings, and effectively prevent freeze injury and death of Pinus tabulaeformis seedlings caused by physiological drought. The method of covering soil with cold is suitable for evergreen coniferous seedlings such as Pinus tabulaeformis and Pinus sylvestris var. mongolica. Pinus sylvestris var. mongolica, Korean pine, spruce, fir, Platycladus orientalis and Sabina vulgaris, and some deciduous flowering shrubs, such as roses, Chinese rose and evergreen boxwood. This method is not suitable for moldy tree species. The cold-proof time of covering soil should be carried out when the seedlings of Pinus tabulaeformis stop growing, the soil freezes for 3-5 days (around beginning of winter) and the temperature stabilizes at about 0℃. The concrete method of covering the soil for cold protection is to plough out the path (or furrow) with a plow, and cover the soil in one direction on the bed (ridge) surface after breaking the soil, so that the seedling tip inclines to one side, and do not cover the soil from the seedling top. Cover the soil evenly and bury it tightly to avoid freezing injury caused by soil ventilation. Generally, the windward side of the south side of the bed surface should be properly thickened. Check frequently after covering the soil, and cover the bare seedlings in time. When the temperature is stable at about 5℃ before 1 ~ 2 weeks in the spring of the following year, the soil should be cultivated twice, not on windy days, which is beneficial to slow down the seedlings and make them gradually adapt to the changes of environmental conditions. The soil should not be removed too late, otherwise the soil will thaw and sink, and the seedlings of Pinus tabulaeformis will attach, which will affect the growth and make the operation inconvenient. Irrigation should be done in time after digging to prevent spring drought. Cover the seedbed with straw, weeds, wheat straw, etc. Prevent frostbite. In early winter, the soil should be covered when it freezes, and the thickness is slightly smaller than that of seedlings. When it snows for the first time, the grassland should be shaken to make the snow fall into the gap between the rows of Pinus tabulaeformis seedlings, so as to avoid further snowfall crushing the seedlings of Pinus tabulaeformis. Before emergence in spring 1 week, the weeds should be removed for 2 ~3 times to avoid weeding prematurely and freezing the seedlings of Chinese pine. Before covering with grass, if the seedbed is too dry, irrigation can be carried out to keep the soil moist, but irrigation is not suitable after the soil is frozen. Covering grass for cold protection is not as good as covering soil for cold protection, but in some nurseries where the soil is too sticky to cover soil for cold protection, covering grass for cold protection is often used. This method is used in large-scale nursery, which consumes manpower and material resources and is inconvenient to manage. ? The method of painting white has a certain effect on the overwintering cold protection of Pinus tabulaeformis seedlings. The specific method is: 1: 1. 5. Add 1% Bordeaux solution with increased lime content into paste emulsion and spray it on Pinus tabulaeformis seedlings. Spraying time is about before the soil freezes. Throughout the winter, the appearance of Pinus tabulaeformis seedlings is gray, which can not only reflect sunlight and prevent the temperature from changing sharply, but also block the stomata of leaves, inhibit transpiration, protect seedlings and prevent diseases.

Plastic film cold-proof method is widely used in production in recent years. For example, seedbed seedlings such as spruce, fir, yew, arborvitae and juniper are used as sowing seedlings. It is simple and easy to support the seedbed into an arch with iron bars and bamboo pieces and cover it with plastic film to make a small arch shed. Plastic arch shed can be covered with thick grass curtain, which plays a role in preventing cold and keeping warm.

Summary: Pinus tabulaeformis is a positive tree, and its young trees are shade-tolerant, cold-resistant, and prefer weak acid and neutral soil to saline-alkali soil. It is a deep-rooted tree species with developed taproots and deep vertical underground; Lateral roots are also well developed, extending horizontally around, mostly concentrated in the surface layer of soil. Pinus tabulaeformis doesn't have strict requirements on soil nutrients and moisture, but it requires good ventilation, so it grows well in loose soil. If the soil is bonded or has too much moisture and poor ventilation, it will not grow well, which is manifested as early dried bamboo shoots. Can't grow in the flat land with too high groundwater level or the place with seasonal water accumulation. There are mycorrhiza on the absorption roots of Pinus tabulaeformis, which has certain requirements for cultivation conditions.

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