Survival mechanism of garden trees after transplantation

1. 1 Root cutting and root promotion

Generally, the range of root cutting should be determined according to the diameter of the trunk. Usually, the diameter of the soil ball should not be less than 5 ~ 6 times the diameter of the trunk of the moved tree. For big seedlings whose trunk diameter is below 10cm and transplanted 1 ~ 2 times, it is only necessary to dig soil balls and transplant them according to the conventional requirements, and it is not necessary to cut roots and promote roots. For trees with trunk diameter greater than 20cm, which have not been transplanted for 5 ~ 8 years, or have been transplanted once since seedling stage, root cutting and root promotion must be carried out first. The specific method is: dig a hole and slot on the opposite sides of the trunk, 2 ~ 2.5 times the diameter of the trunk, cut off the thick lateral roots, preferably with a saw or a sharp axe, and the cross section must be flat to facilitate wound healing and rooting at the lower side. The smaller lateral roots can be cut off with scissors and then covered with fine soil; For Cinnamomum camphora, 10 ~ 20 mg/kg of ABT rooting powder No.3 solution can be mixed with loess to form a thin paste, which can be applied to the cross-sectional wound of thick lateral roots and then covered with fine soil to promote wound healing and extract new fine roots from lateral roots. In the second year, the other side is treated with root cutting and root promotion, and the transplanting operation can only be carried out in the third spring. In the process of cutting, if it is found that there are too many thick roots to be cut off, or the root cutting around the circumference of Cinnamomum camphora with a trunk diameter of more than 20cm is completed at one time, it is best to cut off the main tip of the trunk and the lateral tip of the thick lateral branch at the same time, and the cutting force is generally about 1/4 ~ 1/3 of its total length to reduce leaf transpiration, but the trunk and lateral branches should be wrapped with clean films. It is best to arrange root cutting and root promotion in late autumn, early winter or early spring to facilitate wound healing and promote new roots.

1.2 truncation and branch contraction

Cinnamomum camphora has been rooted on all sides for two years. Before digging, the plants that were not cut off during root cutting should be cut off first, and then cut off. Usually, the trunk height of street trees is controlled at 3.0~3.5m, and the thick lateral branches are kept at about 0.3 ~ 0.5m; the trunk height of trees used in parks and green spaces is kept at 4.5 ~ 6m, and the thick lateral branches are reserved. Immediately after cutting, seal the section with wax, or wrap the section tightly with film to prevent the trunk from losing water.

1.3 Pilling and dressing

Generally, before digging the soil ball, the north-south direction of the trunk should be marked first, so that it can be planted in the original direction, which is not only conducive to survival, but also conducive to preventing the bark on the shady side from being sunburned in summer and the dry skin on the sunny side from being frostbitten in winter. According to the requirement that the diameter of soil ball is not less than 5 ~ 6 times of the dry diameter of camphor tree, shovel the floating soil on the upper layer of the bag to see the densely staggered roots on the ground; Then dig ditches around, and pay attention to protect the newly sprouted fine fibrous roots after root cutting. The transplanted Cinnamomum camphora generally has no longitudinal main roots, only lateral roots; Usually, the thickness of the soil ball is determined by not seeing too many fine roots under the reserved soil ball, which can be controlled between 80 ~ 100 cm. When digging the earth ball, you should wrap it with straw rope while digging to ensure that the earth ball does not come loose. In the process of lifting the soil ball, be sure to handle it gently, don't collide with the soil ball, and don't strangle the trunk bark, so as not to affect the survival.

1.4 package cross section

It is more convenient and easier to encapsulate the wounds in the cutting parts of the trunk and side branches of Cinnamomum camphora after it is laid down and before planting. There are two packaging methods: one is to wrap the cutting section with plastic film, and then wrap the cutting section or cutting section tightly with square film, which can effectively prevent the loss of water in the section, which is very important to ensure the survival of transplanted trees, especially after long-term drought. In addition, it can also prevent the slices from becoming moldy due to the infection of miscellaneous bacteria. The second is to seal the slice with paraffin, so that the block solid mineral paraffin will melt after being heated slightly with enamel utensils, and then be evenly coated on the slice with a brush before solidification, so that a tight protective layer can be formed. The sealing section can obviously shorten the contraction length of the incision, especially the contraction part of the wax sealing incision moves down to the minimum.

1.5 Planting and watering

First, dig a planting pit in a predetermined place. Generally, the diameter of planting holes is about 1/3 larger than that of soil balls of camphor trees. The depth depends on the groundwater level in the planting area. The bottom of the soil ball should be above the normal groundwater level, usually controlled at about 80 ~ 65,438+000 cm to prevent the root rot caused by stagnant water and the death of transplanted trees. When planting, first put fertile fine soil on the bottom of the planting hole, then put the big tree with soil balls into the planting hole, plant it in the original marked north-south direction or according to the aesthetic requirements of the planting place, and then cut the straw rope and take it away to avoid the influence of heating when the grass is moldy on root healing and fine fibrous root growth; Fill in the fertile fine soil layer by layer, and tamp it with a thick stick every time you fill in the fine soil with a thickness of 30cm. When 10 ~ 20cm is not filled, it shall be filled with clear water to make the filled soil and soil ball absorb water. Fill in the remaining soil until the base of the trunk bulges slightly.

1.6 grass wrapping

In order to prevent the evaporation loss of trunk water and improve the survival rate of camphor tree transplantation, it is the key to wrap the trunk with grass and film to keep it moist. In the past, one of the fundamental reasons for the low survival rate of camphor tree transplantation was that the water in the trunk was not preserved after transplantation, which led to the imbalance of water budget and led to the death of the tree. There are three ways to moisturize the trunk, which can be selected according to the specific situation:

(1) Wrap the straw and bind the film: first wrap the trunk with a straw curtain or directly with straw, and then fix it on the trunk with a thin straw rope; Then spray the straw with a water pipe or sprayer, or soak the straw curtain or straw and wrap it; Then wrap the straw curtain or straw with plastic film, and finally tie the film to the trunk with plastic bandage, so that the film can be laid on the lower part of the trunk near the soil ball. After the substrate is covered with soil and watered, it is covered with plastic film together with the diameter of soil balls around the dry bag, and the periphery of the plastic film is well compacted with the soil, so that the adjustment of soil moisture can be used to ensure sufficient temperature and humidity in the trunk space of the package, and the work of supplementary watering can be omitted.

(2) Rope winding and film winding: firstly, tie the trunk tightly with thick straw rope, and fill the straw rope with water, and tie a plastic film outside to keep it moist. The method of covering the ground with plastic film at the grass-roots level is the same as (1), which has obvious humidity and temperature control effect and is also conducive to survival.

(3) Bundling grass, film and cloth: When transplanting camphor trees in some beautiful places, such as century avenue, Pudong, Shanghai, wrapping grass and film will affect the elegance of the environment. After wrapping the grass and binding the film, the trunk and branches can be wrapped with a layer of thick white linen, which can be in harmony with the environment, prevent the temperature in the film from being too high in summer, and is also conducive to the moisturizing survival of camphor tree trunks. The operation of wrapping grass and binding film can also be carried out before planting trees, which is more convenient.

1.7 Pile pulling rope

After wrapping grass and binding film to keep moisture, in order to prevent the trunk from swinging loose due to strong wind or pedestrian touch, it is necessary to pile up ropes in time to fix it. For street trees with a common trunk diameter of 10 ~ 15 cm, a wooden stake with a height of about 1 ~ 1.5 m can be made at about 50cm on both sides of the trunk, and a thick horizontal wooden stick is inserted in the middle, which is placed at the upper ends of the two wooden stakes and tied tightly with lead wires at both ends. In the middle of the horizontal stick is the trunk of Cinnamomum camphora, which is tied with a rope. For tall and thick trees, three low stakes can be driven at the periphery of the trunk 1.5m, with one end of thick lead wire or hemp rope tied to the middle and upper part of the trunk and the other end tied to the stakes. However, we should be careful not to hurt the trunk cortex, and it is advisable to add hard binding lining before binding.

2 management measures

2. 1 water spraying

After transplanting, water management is particularly important. When the soil covered with plastic film around the tree pocket is found to be white and dry, it should be watered in time. When it is found that the straw rope wrapped around the trunk or the wrapped straw is dry, the upper end should also be opened, and then tied after supplementary watering, and the straw rope should always be kept wet. In midsummer, Cinnamomum camphora has pulled out many branches and leaves, and it can spray water on the crown once every morning and evening to humidify and cool down.

2.2 Wipe bud and save branches

When Cinnamomum camphora begins to sprout a large number of new buds, it is necessary to erase some too dense branches and buds. For Cinnamomum camphora plants without branches at the trunk cut, 3 ~ 5 thick sprouting strips can be reserved from different angles at the end of 20 ~ 30cm, so as to form umbrella-shaped trunk side branches in the future; For Cinnamomum camphora plants with branches and side branches on the trunk, 3 ~ 4 secondary side branches can be reserved on each side branch to form a complete crown shape as soon as possible and play a role in shading.

2.3 Pest control

After transplanting Cinnamomum camphora, the newly germinated buds and leaves are vulnerable to aphids, and 40% dimethoate EC can be sprayed 2000 times. Cinnamomum camphora is vulnerable to leaf peaks, moths and green thorn moths in the growing season. In severe cases, all the bud leaves will be eaten, and 40% dimethoate EC or 2.5% insecticide EC 1500 ~ 2000 times can be sprayed. When the damage caused by the moth-eaten Monochamus alternatus is found on the trunk, poison sticks can be inserted into the wormhole or pesticides can be injected to block it.

2.4 cold and antifreeze

The cold and antifreeze measures of newly planted Cinnamomum camphora can not be ignored. There are two main situations of freezing injury of Cinnamomum camphora after transplanting. One is that if the cold protection work is not in place, it will cause serious consequences and even the death of the whole factory. Generally speaking, it is suggested to move Cinnamomum camphora from the north to the south, and try to avoid moving Cinnamomum camphora from the south to the northern cities for planting. Second, the degree of lignification of new branches is not high, and it is easy to freeze to death in winter. The measures for preventing cold and freezing are: for the big trees transplanted in the spring of that year, don't take off the straw curtain or straw rope in winter, loosen it in the second spring, and wrap the rope in the third winter to prevent cold, so that they can gradually adapt to the low temperature in the winter of the transplant site. For the newly drawn thick green lateral branches, straw rope or film can be used to wrap them for cold protection, which can safely overwinter until the thick skin is grayish brown. When the weather forecast was particularly cold in winter that year, it was best to wrap grass around the trunk between the Yangtze River and Huaihe River, whether it was a newly planted tree or a tree that had been transplanted for several years.