A paper analyzing the key points of transplanting technology for large pine trees

Abstract: Pinus tabulaeformis is widely distributed and is one of the most important afforestation tree species in the vast areas of northern China. Pinus tabulaeformis has strong adaptability, well-developed root system, majestic tree appearance, luxuriant branches and leaves, and has good functions of maintaining soil and water and beautifying the environment. Chinese working people have a long history of cultivating Chinese pine. When transplanting Chinese pine, the tree body must be properly treated. In order to ensure the survival of the big tree and promote the growth of the tree's fibrous roots, multiple transplanting methods, pre-root cutting methods, and root girdling methods are often used to treat the roots in advance. Before raising the tree, gravel, rubble, bushes, etc. within 2-3m around the trunk should also be cleared away. Large trees should be supported with three pillars to prevent lodging, causing work-related injuries and damage to the tree. When transplanting large trees in batches, the trees must be numbered and oriented, and the north and south directions must be marked on the trunks so that they can maintain their original orientation after transplanting to meet the needs for shade and sunlight.

Keywords: Pinus tabulaeformis transplantation techniques and methods

1. Preliminary preparations

1. Select trees: Choose trees that are strong, Young and mature trees that are in the ascending growth stage, but it is not advisable to choose trees that are too vigorous and new and have a low degree of lignification. When selecting trees in the forest, pay attention to choosing trees with good stem shape, free of diseases and insect pests, and trees as close as possible to the gentle slope of the road to prevent the soil ball from tilting too much, which is not conducive to planting.

2. Root cutting and shrinkage: Due to the large root width of large trees, the absorbing roots at the base of the trunk are more centrifugal and die. The soil lumps brought during transplanting cannot take away many absorbing roots, which will cause the big tree to lose weight. Metabolism imbalance between aboveground and underground parts leads to transplant failure. Therefore, where conditions permit, measures can be taken one year or even several years in advance to remove the roots of selected trees and promote the formation of a large number of absorbing roots in the soil ball, thereby improving the survival rate of transplanted trees.

2. Selection of transplanting time:

Transplanting of large pine trees can be carried out in spring, summer and autumn, but autumn is the best because the upper branches and leaves of the tree are in autumn. Growth slows down and transpiration decreases, but root growth can still continue for about 1 month. At this time, transplanting, the root system will resume growth after 1 month, and some new roots can grow. When the branches and leaves on the tree begin to transpire in the following spring, new growth will begin. The root system can already absorb water from the soil, thus improving the survival rate of the transplant.

3. Seedling packaging and transportation:

1. Digging seedlings: After selecting the trees, determine the size of the soil ball according to 7-10 times the diameter of the tree, and dig the seedlings as needed. Trim the soil ball into an "apple shape". If you encounter larger lateral roots, cut them off with pruners or a hand saw. Do not chop them with a shovel to avoid dispersing the soil balls.

2. Wrapping balls: In addition to transplanting large trees, large soil balls need to be packed with wooden boards and generally tied with straw ropes. When choosing a straw rope, it should generally be thicker than a person's index finger. After it is fully soaked in water, tie the soil ball firmly and extend it to the trunk. Bundling part of the trunk can keep the trunk moist and avoid damaging the trunk surface when planting the tree.

3. Transportation: When trees are placed at an angle during transportation, brackets should be installed on the transport vehicle to prevent the lower branches from being broken, and straw ropes should be tied at the contact points between the brackets and the trunk to protect the trunk. .

4. Planting:

When transplanting large trees, it is necessary to follow the steps, transport them, plant them and water them.

1. The diameter of the planting hole should be 1.2 to 1.3 times larger than the soil ball. The bottom layer of the planting hole should be loosened to a depth of 10-15cm to facilitate the adjustment of the plant trunk and the growth of the root system. The planting depth should be slightly deeper than the original 2-3cm.

2. Adjust the orientation of the trees. While considering turning the best side of the tree toward the viewing surface, full consideration should be given to keeping the original sunny side of the tree toward the sunny side to prevent shade burns due to reversal of direction. tree trunk.

3. After the tree trunks are planted, use poles to make triangular supports to fix the trees. The contact point between the bracket and the trunk should be tied with straw rope to prevent damage to the trunk due to wind, shaking and friction.

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

5. Use of chemicals:

1. In order to promote rooting, 0.001% auxin can be applied to the root system.

2. For tree trunks damaged during seedling digging and lifting, the wounds must be repaired and wound patching agents applied.

3. Use 70% high-efficiency cypermethrin or 40% phoxim emulsion on the crown of the tree before planting to fully prevent insects. After loading, spray the bracket and trunk again.

6. Later management of trees

Careful maintenance of pine trees after transplantation is one of the important links to ensure the survival of the transplant and the healthy growth of the tree, and must not be ignored.

1. To support the tree trunk, the three-column support and fixation method is generally used to firmly support the tree and ensure the stability of the Chinese pine. Generally, it can be removed after one year after the root system of the Chinese pine has recovered.

2. Water and fertilizer management. After transplanting the Chinese pine, immediately irrigate once with water to ensure that the tree roots are closely integrated with the soil and promote root development. Then water 3 times in a row. After irrigation, seal the tree tray with fine soil in a timely manner. Or use mulching film to protect moisture and prevent topsoil from cracking and ventilation. When watering, we must follow the principle of "don't water dry, water thoroughly". In summer, spray water on the ground and tree crowns more often to increase the ambient temperature and reduce transpiration. Due to the heavy damage, no fertilizer can be applied in the first year. In the second year, farmyard manure should be applied according to the growth conditions.

3. Auxin treatment, in order to promote new roots, 200mg/T naphthalene acid or ABT rooting powder can be added in combination with watering to promote early and rapid root development.

4. Wrap the trunk. In order to maintain the humidity of the trunk and reduce the evaporation of bark water, you can use soaked straw ropes to wrap tightly from the base of the trunk to the top of the trunk, and then paste the prepared clay mud on it.

7. Cold protection measures

Northern China has cold winters, strong winds, droughts, and drastic temperature changes in spring, which are very harmful to pine seedlings. In order to ensure the safe overwintering of pine seedlings and avoid the death of pine seedlings due to frost and physiological drought, effective cold protection measures should be taken, especially for some evergreen tree species, newly introduced southern tree species and some seedlings with weak cold resistance. The cold protection of Chinese pine seedlings is mainly to prevent freezing damage, freeze pullout and physiological drought. The specific measures are as follows: Covering soil to prevent cold: Covering soil to prevent cold means burying the overwintering Chinese pine seedlings in the soil throughout the winter to keep the Chinese pine seedlings and seedbed soil at a certain temperature. , not affected by sharp changes in temperature and other adverse external factors. At the same time, it can reduce the transpiration of water in pine seedlings and the evaporation of soil water, maintain a certain amount of soil moisture, and help maintain the water balance in the seedlings. It can effectively prevent frost damage and death caused by physiological drought in pine seedlings. The soil-covering cold protection method is suitable for evergreen coniferous tree seedlings such as Pinus tabulaeformis, Pinus sylvestris, Korean pine, spruce, fir, arborvitae, and juniper, as well as some deciduous flowering shrubs, such as roses, roses, and evergreen small-leaf boxwoods. This method is not suitable for tree species that are prone to mold and rot. Covering with soil to prevent cold should be carried out when the pine seedlings have stopped growing, 3 to 5 days before the soil freezes (before and after the beginning of winter), and when the temperature stabilizes at around 0°C. The specific method of covering soil to prevent cold is to plow up the footpath (or furrow) with a plow, break up the soil, and then cover the bed (ridge) surface with soil in one direction so that the seedling tips fall to one side. Do not cover the soil from the top of the seedling downward. The covering soil should be even and buried tightly to avoid freezing damage caused by soil ventilation. Generally, the covering soil should be appropriately thickened on the windward side of the south side of the bed. After covering with soil, check frequently and cover the seedlings promptly if any dew seedlings are found. One to two weeks before the emergence of seedlings in the following spring, when the temperature stabilizes at around 5°C, the soil should be removed in two batches. Do not remove the soil on windy days. This will help slow down the seedlings and enable them to gradually adapt to changes in environmental conditions. The soil should not be removed too late, otherwise the covering soil will thaw and sink, adhering to the pine seedlings, affecting their growth and making operation inconvenient. Irrigation should be done promptly after soil removal to prevent spring drought. Covering with grass to prevent cold: Use straw, weeds, wheat straw, etc. to cover the seedbed to prevent frost damage. When the soil freezes in early winter, cover it with a thickness that does not expose the seedlings. When it snows for the first time, the grass should be shaken and mulched so that the snow falls into the rows of Chinese pine seedlings and fills the gaps to prevent further snowfall from crushing the Chinese pine seedlings. One week before seedling emergence in spring, remove the grass cover in 2 to 3 times to prevent the pine seedlings from suffering frost if the grass is removed too early. If the seedbed is too dry before covering with grass, you can irrigate to keep the soil moist, but avoid irrigating after the soil freezes. Mulching with grass to prevent cold is not as effective as covering with soil to prevent cold. However, in some nurseries with heavy soil and it is not suitable to cover with soil to prevent cold, mulching with grass is often used to prevent cold. Applying this method to a large nursery over a large area is labor-intensive, material-intensive, and inconvenient to manage. ? Painting white for cold protection has a certain effect on pine seedlings overwintering and protecting against cold. The specific method is: prepare 1:1.5 1% Bordeaux mixture with increased lime content and paste emulsion, and spray it on the pine seedlings. The time to spray is approximately before the soil freezes. Throughout the winter, the appearance of pine seedlings is gray-white, which can not only reflect sunlight and prevent rapid changes in temperature, but also block the stomata of leaves, inhibit transpiration, protect seedlings, and prevent diseases.

Plastic film cold protection method This cold protection method has been widely promoted and applied in production in recent years. For example, the seedlings of spruce, fir, yew, arborvitae, juniper and other beds are sown with iron bars and bamboo chips. Support the seedbed in an arch shape, cover it with plastic film to make a small arch, and bury it tightly with soil around it, which is simple and easy to do. Before covering the film, fill it with bottom water. The film can be used for thermal insulation and moisturizing, suitable temperature and humidity, and easy management. If it is cold in winter, a thick straw curtain can be covered on the plastic arch to prevent cold and heat preservation.

Summary: Pinus tabulaeformis is a positive tree. The saplings tolerate side shade and have strong cold resistance. They like slightly acidic and neutral soil and are not tolerant to salt and alkali. It is a deep-rooted tree species with well-developed main roots that extend vertically deep into the ground; lateral roots are also well-developed, extending horizontally around and mostly concentrated on the surface of the soil. Pinus tabulaeformis does not have strict requirements for soil nutrients and moisture, but requires good soil aeration, so it grows better in loose soil. If the soil is sticky or has too much water and poor ventilation, the growth will be poor, which will be manifested as early dry shoots. It cannot grow on flat land where the water table is too high or where there is seasonal water accumulation. There are mycorrhizae growing on the absorptive roots of Pinus tabulaeformis, so there are certain requirements on cultivation conditions.

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