What are the transplanting techniques of big trees in garden trees?

In recent years, urban landscape construction has developed rapidly. According to the characteristics of urban environment and the needs of urban construction, some greening projects, especially some key greening projects such as streets, squares and major construction projects, need to choose to plant large areas of seedlings or trees with specific beautiful tree postures in order to achieve early results. This can only be achieved by transplanting big trees.

Compared with ordinary saplings, big tree transplantation has its own characteristics. As far as the tree itself is concerned, its roots are in the trend of centrifugal growth or have reached the maximum root width, while the absorption roots of the trunk roots mostly die centrifugally, mainly distributed near the crown projection. The soil ball (lump) brought by transplantation can't be that big; That is to say, there are few absorbing roots in the range where soil is generally needed. This will make the transplanted trees seriously lose the balance of water metabolism. For the crown, in order to give full play to the greening effect as soon as possible and maintain the original graceful posture, there is no need for excessive pruning, and only a large number of new roots can be promoted in advance within the scope of soil balls, laying the foundation for metabolic balance. And cooperate with other transplanting measures to ensure survival.

In addition, compared with ordinary saplings, big tree transplantation is mainly manifested in the huge tree body and considerable weight of the objects to be moved. Therefore, it often needs the help of certain mechanical strength to complete.

The success of tree transplantation mainly depends on the number of roots absorbed within the scope of soil balls, and is also closely related to digging, lifting, planting and future maintenance techniques.

1. Preparation and treatment of big trees

(1) Make plans and schemes.

In order to promote the absorption of roots in soil balls (blocks) in advance, measures need to be taken one to several years in advance, and whether measures can be taken in advance depends on whether there are plans and schemes for greening trees. In fact, the reason why many big trees failed to transplant is that the spare big trees with root promotion measures were not prepared in advance, but transplanted directly from the suburbs and Shan Ye as a temporary emergency task. It can be seen that planning and planning are extremely important for tree transplantation.

(2) Choose trees

Field investigation should be conducted on the transplanted trees in suburbs and other places, including tree species, tree age, dry height, dry diameter, tree height, crown width, tree shape, etc., and measurement records should be made, indicating the best viewing surface orientation, and photography should be carried out. Investigate and record soil conditions and surrounding conditions; Judge whether it is suitable for excavation, packaging and hoisting; Analysis of existing problems and solutions, in addition, we should also understand the ownership of trees. The selected trees should be numbered by cards to provide data for the design.

(3) Root cutting and block shrinking

In ancient times, it was called root-returning method and packing method. First, according to the habit, age and growth status of the tree species, the difficulty of transplanting survival is judged, and it is decided to ditch outside a certain range in the east, west, south and north (or around) within two to three years, and only 1/3 ~ 1/2 of the perimeter is broken every year (as shown in figure 1). Generally, a ditch with a width of 30 ~ 40 cm and a depth of 50 ~ 70 cm (depending on the depth of the root) is opened outside the circle (or square) with a diameter of 5 times (including the diameter of the trunk) in the range of root cutting. When digging, it is best to only cut off the fine roots, leave the thick roots above 1cm, and peel them into a circle at the wall of the soil ball with a line width of about 10cm. Apply 0.00 1% auxin (naphthylacetic acid, etc. ) is conducive to promoting new roots. Fill in the topsoil, reach the ground level properly, and then water it. In order to prevent the wind from blowing down, three-legged support should be set up.

Figure 1 Root cutting and shrinking method

2. Preparation before excavation

The trees selected according to the design should be inspected on the spot to see whether they meet the original conditions, especially whether there are moths on the trunk. If there is a problem, you should choose another tree instead. After specific selection, they shall be numbered and marked according to the planting design, so that they can sit properly when planting. If the soil is too dry, water it a few days before excavation. At the same time, there should be a special person responsible for preparing the required tools, materials, machinery and lifting vehicles. In addition, it is necessary to investigate whether there are obstacles in the traffic lines (such as the height of overhead lines and the construction of roads, etc.). ) and apply for a pass.

3. Christmas Tree Lifting and Packaging

After cutting roots and shrinking piles 2 ~ 3 years in advance, many new roots appeared inside and outside the stump, especially outside the stump. Therefore, when excavating and transplanting, the size of clods (balls or blocks) should be wider 10 ~ 20 cm than that of root cutting blocks. In order to reduce the weight of the mound, it is necessary to shovel off the topsoil (based on the root, commonly known as "lifting the treasure cover" in the north). Other excavation and packaging technologies are different according to the specific transplanting methods.

(1) Soft material packaging of soil ball is suitable for tree transplantation in DBH 10 ~ 15cm. Soft material can be used when the soil ball does not exceed1.3 m. In order to ensure safety, the trunk should be supported above the branch point with a stick. Draw a circle with the trunk as the center and the enlarged mound size as the radius, and dig a ditch with a width of about 60 ~ 80 cm vertically outward (convenient for human operation) until the specified depth (i.e. the height of the mound). Use an iron mill to smooth the shoulder of the soil ball. When the surrounding soil surface is leveled from top to bottom to half a ball height, it gradually shrinks inward (the bottom diameter is about 65438+ 0/3 of the upper diameter), showing a roughly smaller shape. Deep-rooted tree species and sandy loam balls should be "red star apple shape"; Shallow roots and cohesive soil can be oblate. The thick roots should be sawed, and the loose blocks should not be caused by hard shoveling. Straighten the pre-wetted straw rope first (so as not to break it) and wrap the rope around the soil ball. The two will cooperate with the pulling and wrapping, and beat the straw rope with a wooden hammer (or brick or stone) so that the rope is slightly embedded in the soil ball (the same below). To make each circle of straw rope close together, the total width is 1/4 ~ 1/3 (about 20cm) of the height of the soil ball, so it can be fastened. The upper part of the soil ball is decorated as a convex mirror with a slightly higher dry base center and a gradually lower edge. Dig a circle of ditches downward at the bottom of the soil ball and shovel the soil inward until the core soil of 1/4 ~ 1/5 remains; In the case of thick roots, the soil should be hollowed out and sawed off. This helps the straw rope to bypass the bottom edge and is not easy to loosen. Then pack it with materials such as cattail bags and straw ropes. For loam and sandy soil, the soil ball should be tightly covered with a cattail bag or a plastic sheet, slightly tied with a string, and then wrapped with a straw rope; Cohesive soil can be directly wrapped with straw rope. Straw rope has three winding ways:

(1) orange type: firstly, tie one end of the straw rope to the trunk (or waist rope), slightly incline through the bottom of the soil ball and bypass the opposite side, then turn back through the trunk at about half of the spherical surface, and wind it in the same direction at a certain interval (depending on the soil) until the ball is full. Then go around the second lap, and the shoulders of the first lap are pressed neatly with each straw rope until they are full. Then a dozen outer waist ropes are tied to the lower part of the inner waist rope, and then the inner and outer waist ropes are connected in a zigzag manner. Finally, along the outer edge of the soil ball, dig an arc ditch in the direction where the tree is planned to be pushed down, and gently push down the tree, so that the trunk will not touch the edge of the hole and be damaged. Loam and sandy soil need to be padded at the bottom of the soil ball with a cattail bag and tied tightly with a straw rope along the longitudinal rope (as shown in Figure 2).

Fig. 2 Schematic diagram of orange dressing method

② Tick-tac-toe (ancient money) method: firstly, tie one end of the straw rope to the waist band, then according to the numerical sequence shown in the schematic diagram of Figure 3, pull it from 1 to 2, bypass the soil ball to 3, bypass the soil ball to 5-4, bypass the soil ball to 7-6, and then pass 8 and 1 near the parallel Lazar. Wrap 6 ~ 7 patterns in this order until they are full.

Fig. 3 schematic diagram of tic-tac-toe game binding method

③ First, tie one end of the straw rope to the waist hoop in a pentagonal way, and then wind it according to the numerical order shown in Figure 4. First pull from 1 to 2, bypass the soil ball bottom, pass through the soil ball surface from 3 to 4, bypass the soil ball bottom from 5 to 6, bypass the soil ball bottom, pass through the soil ball surface from 7 to 8, and bypass the soil ball bottom from 9 to 10. In this order, there are 6 ~ 7 five-pointed stars next to Pinza, which are juxtaposed as shown in the figure.

Fig. 4 schematic diagram of pentagonal binding method

Tick-tac-toe and pentagon are suitable for cohesive soil and deciduous trees or evergreen trees below 1 ton not far from transportation; Otherwise, orange, tic-tac-toe and pentagonal are all suitable.

(2) The square box with clods is suitable for transplanting trees with trunk diameter of 15 ~ 30cm or more and big trees in sandy soil.

① Preparation of box boards, tools and cranes. A: Prepare four inverted trapezoidal wallboard (upper bottom length 1.85m, lower bottom length 1.75m, and height 0.8m) with 5cm thick tough wooden boards, and nail them firmly with three vertical battens with the width of 10 ~ 15 cm, which are the same height as the box boards. 4 bottom plates (about 25cm wide and the length is the bottom length of the box plate, plus 2 slats with the same thickness as the wallboard); 2 ~ 4 cover plates (about 25cm wide, 2 slats with the same thickness as the wallboard) and perforated iron sheets (about 80 ~ 100 nails, 0.2cm thick, 3cm wide and 80 ~ 90 cm long) and 10 ~ 12 cm (about 800 nails are prepared) D: 1 hydraulic jack. E: cranes and trucks. Clod thickness 1m, in which 1.5m is measured by a 5-ton crane; 1.8m square, 8-ton crane; 2 meters square, equipped with 15t crane and corresponding trucks. F: Three Chinese fir trees slightly taller than the trees are used as backup support.

(2) Before digging, support the trunk firmly with three long Chinese fir trees. Draw a square with the trunk as the center, add 5cm according to the predetermined expansion size, and dig a ditch of 60 ~ 80 cm vertically outside the line until the specified depth (as shown in Figure 5). Trim the four walls of the clod into an inverted trapezoid with a slight bulge in the middle, which is slightly larger than the wallboard (as shown in Figure 6). Avoid using shovels when encountering thick roots. The soil around the root can be slightly recessed, and the root can be cut off, so as not to be flush with the soil wall, so as to ensure that the four wallboard tightly stick to the soil after tightening.

Fig. 5 Excavation of square luggage clods

Figure 6 patched clods and boxes.

(3) The middle of the box wall of the upper box board is aligned with the center line of the trunk, the lower openings of the four wall boards should be aligned, and the edge of the upper opening is slightly lower than the clod. Do not push the ends of the two boxes, so as not to affect the tightening. Fix it with a stick. Two wire ropes shall be placed at a distance of 15 ~ 20 cm from the upper and lower openings, and the upper clip shall not be stuck on the slats outside the wallboard. Place a log pier between the wire rope and the batten of the wallboard, tighten the wallboard with a rope tightener (as shown in Figure 7), and nail iron sheets between the four corner wallboard (as shown in Figure 8). Then dig the ditch to a depth of 30 ~ 40 cm, fix the box board and the pit wall with square wood (as shown in Figure 9), dig the small board to the bottom of the clod with a short hoe (as shown in Figure 10) for a certain width, and then install the floor. Put a short wooden pier at one end, jack it up at the other end, nail it with iron sheet, support the square wooden pier at four corners, then dig it in, and nail the second floor every 10 ~ 15 cm. If the root is thick, remove the soil around the root and saw it off. If the soil is found to be loose, it should be supported by a cattail bag and then placed on the floor. Finally, nail parallel or well-shaped slats on both sides of the trunk on the surface of the clod.

Fig. 7 Compaction method of box board and rope tightener

Fig. 8 Method of nailing iron sheet

Fig. 9 Supporting method for upper part of clods

Figure 10 Dig the bottom from both sides

Step 4 lift your heels

Before lifting, remove the bracket and fasten the crown. Locomotive with lifting and loading capacity greater than tree weight and crane type suitable for field application should be selected. For example, crawler cranes should be used in soft soil. The soft material is packed at about 3/5 of the lower part of the soil ball, wrapped with thick rope and padded with wooden boards. The square box can be wrapped with steel wire rope at the lower part of the wooden box 1/3. Another thick rope is tied to the proper position of the trunk (the outer side of the trunk should be padded), so that the hoisted tree can be slightly tilted. If the crown block is large, tie a traction rope at the branch to facilitate the direction of the crown block when loading. The center of gravity of the clay ball and wooden box should be placed on the rear axle of the car, and the crown should face the rear of the car. If the road arch is too large, a crossbar should be set at the back of the carriage. The two sides of the lower part of the soil ball should be stabilized with east-west plugs. The wooden box should be fastened to the body, and the trunk should be fastened to the hook at the rear of the truck. When transporting trees, people who are familiar with the route and other conditions should stand near the trunk (don't stand at the earth ball and square box) to escort them, and be equipped with insulating tools to support wires, such as sticks such as bamboo poles.

If it is packed in a square box after being transported to the planting site, if it is not planted immediately, the upper wood should be padded at the moment of unloading, so that it can be used to thread the wire rope when planting and hoisting. If you can't plant it within half a month, you should change the heel. If the quantity is large, you should focus on changing the heel and maintain it according to the above method.

5. Planting and maintenance

Check the hole and sit down. The planting holes in the square box are also square, each side is 50 ~ 60 cm wider than the box and the depth is 15 ~ 20 cm. Measure the depth of the original soil trace from the bottom of the wooden box to the trunk, check and adjust the specifications of the pit to make it flush with the planted soil. If the soil is not good, it should be increased. Soil replacement or fertilization should be prepared in advance, and fertilizer should be mixed with topsoil. Before planting, pile a rectangular soil platform with a height of 15 ~ 20 cm and a width of 70 ~ 80 cm in the center of the pit, with the long side in the same direction as the bottom of the box. Wear steel wire rope at the bottom of both sides of the box and hang it vertically. If the subsoil is not loose, the two bottom plates in the middle should be removed before being put down. When entering the cave, you should face the main viewing surface in the best posture. When landing near the ground, one person is responsible for aiming, and four people sit by the pit and put the top of the wooden box in the right position with their feet. Then remove the bottom plates on both sides, pull out the wire rope, and fix the crown block with long poles. Fill in the topsoil mixed with fertilizer to 1/3, then dismantle the four-sided wallboard to avoid loosening and caking, and tamp it before filling; Compaction 1 time every 20 ~ 30cm until it is compacted. According to the size of clods and pits, a double-ring irrigation weir is made, and the inner and outer hydrosphere are irrigated at the same time. Other post-planting maintenance is basically the same as before.