Prune to keep the growth balance between the above-ground and underground parts.

Tree pruning shall meet the following requirements:

Deciduous trees should maintain the original tree shape, properly sparse branches, and keep the main side branches evenly distributed. The reserved main lateral branches should be cut short above the robust leaf buds, and the branches of 1/5~2/3 can be cut off. Trees with main shoots should keep the main shoots, such as ginkgo biloba, which can only be thinned and cannot be cut short. Pruning-resistant tree species such as Sophora japonica and Luan tree should not be pruned.

Evergreen conifers only cut off pests and diseases, dead branches, weak branches, over-dense rotation and drooping techniques.

For trees used as street trees, the height of the branch point should be greater than 2.8 m, and the branches above the branch point should be drained or cut down as appropriate.

Shrubs and rattan pruning shall meet the following requirements:

There are obvious trunk shrubs. When pruning, the original tree type should be maintained, the main branches should be evenly distributed, and the length of main branches should not exceed 1/2.

The reserved branches of clump shrubs are more than 30 cm, and the branches of dry shrubs should be properly thinned.

Seedlings used as hedges, color blocks and shapes should be pruned according to the design requirements after planting.

Rattan seedlings should be cut off from dead branches, pests and diseases, and parts that affect the appearance. Brawly can cut off staggered branches and lateral branches.

The quality of seedling pruning shall meet the following requirements:

The incision should be smooth and not split.

When the branches are cut short, the outer buds should be left, and the incision should be located 0.5 cm above the bud position.

When pruning large branches and thick roots with a diameter of more than 2 cm, the section must be flattened and coated with preservatives.

For deciduous trees transplanted in the growing season, they should be pruned according to different tree species on the premise of maintaining the tree shape to ensure survival.

plant trees

Trees in Beijing should be planted mainly in spring, evergreen trees can be planted in rainy season, and cold-resistant deciduous trees can be planted after defoliation in autumn.

The quality of planting construction shall meet the following requirements:

Planting should check the varieties, specifications and planting position of seedlings according to the requirements of design drawings.

Before planting trees in planting holes, the size and depth of planting holes should be checked first. If it does not meet the requirements of the root system, the planting hole should be trimmed.

Trees planted along the street or in rows and columns in Ying Chengyi have reasonable specifications and similar heights, trunk diameters and tree shapes. The planted trees should be kept upright and not inclined, and supported by columns. At the same time, we should pay attention to the reasonable orientation of the viewing surface.

Generally, the planting depth of trees and shrubs should be equal to the original planting line. Individual trees with fast growth and adventitious roots can be planted 5 cm ~ 10cm deeper than the original soil trace, and the soil ball should be slightly higher than the ground 5 cm when planting evergreen trees. Bamboo can be 5 cm; Deeper than the original planting line; The root system of tree planting must be elongated, and the filling should be layered and practical.

When planting bare-rooted trees, the fill at the bottom of the planting hole should be a semi-circular mound. When the tree fill is placed in 1/2, the trunk should be lifted gently to stretch the roots and make full contact with the soil.

Trees with soil balls must loosen the soil at the bottom of the hole before entering the hole, put the soil balls firmly, erect the trunk, and then unpack and take out the non-perishable packaging.

Planting hedgerows should be replanted from the center to the outside in turn; Slope planting should be planted from top to bottom; When planting large clumps or clumps of different colors, it is advisable to plant them in blocks.

Hedges and hedges should be evenly spaced. The plump side of the tree should be outward and evenly matched according to the height of the seedlings and the crown size.

When planting in rockeries or crevices, moisturizing and breathable materials such as moss and peat should be mixed in the planting soil.

For planting holes with poor drainage, gravel of 10 cm~ 15 cm can be laid at the bottom of the hole or seepage pipes can be laid, and blind ditches can be added to facilitate drainage.

Trees shall be supported, fixed and watered in accordance with the following provisions:

After planting, an irrigation cofferdam with a height of 15 cm~20 cm should be built around the planting hole with a slightly larger diameter, and a watertight weir should be built.

Planting trees should be fixed with brackets. The support should be firm, the base should be buried below 30 cm, and the place where the trees are tied should be padded, and the trunk should not be worn.

Water the newly planted trees for the first time on the same day, for the second time in three days and for the third time in ten days. After water seepage, the tree hole should be blocked with cofferdam soil in time. When the weir is rebuilt, the root system shall not be destroyed.

When watering, the exposed root system or cofferdam should be prevented from being washed away by water, resulting in water leakage. When the soil sinks after watering, which causes the trees to tilt, they should be righted and ridged in time.

For squares and sidewalks where people gather and distribute more, after planting trees, the planting pond should be paved with breathable pavement and fenced.

Climbing plants should be tied or dragged after planting.

When planting in the growing season, the following technical measures should be taken according to different situations:

Seedlings must be cut in advance in a ring shape, or cultivated in containers such as heels in the right season.

Deciduous trees and shrubs should be pruned vigorously and some side branches should be cut off. The remaining lateral branches should also be drained or cut short to maintain the original crown shape and appropriately increase the volume of soil balls.

If leaves can be removed, some leaves should be removed, but young axillary buds should not be harmed.

In summer, measures such as shading, canopy spraying or spraying anti-transpiration agent can be taken to reduce water evaporation; In winter, heat preservation and moisture preservation measures such as winding straw ropes around tree trunks can be taken to prevent wind and cold.

When digging seedlings, hormones can be sprayed on the roots to promote rooting, and water-retaining agents can be added when planting.

Suitable for planting in rainy days or in the evening.

Transplantation of big trees (excluding old trees)

Transplanting a tree with a trunk diameter of more than 20 cm should be a big tree transplant.

Preparations before transplanting big trees:

Transplanted trees must be experienced technicians or senior workers trained and qualified by the garden department.

Before transplanting trees, the growth, site conditions and surrounding environment of transplanted trees should be investigated and studied, and the technical scheme and safety measures for transplanting should be formulated.

For trees that need to be transplanted, ownership transfer and necessary procedures should be done well in accordance with relevant regulations, and preparations should be made for tools, materials and mechanical equipment needed for construction. Before construction, we should cooperate with transportation, municipal administration, public utilities, telecommunications and other relevant departments to remove construction obstacles and handle necessary procedures.

After selecting the transplanted trees, obvious marks should be made on the south side of the trunk, indicating the sunrise side of the tree, and a tree card should be established, including: tree number, tree species, specifications (height, branch point, trunk diameter, crown width), tree age, growth status, tree position and transplant location. You can also keep photos or videos if necessary.

When big trees need to be transplanted, it is advisable to cut roots and prune them in stages 1 ~2 years before transplantation, and make good preparations for transplantation.

Transplanted trees should be trees without pests and diseases, obvious mechanical damage, good ornamental, strong plants and normal growth, and have mechanical energy for hoisting and transportation to meet the site conditions of transplanted trees.

Tree transplantation should follow the following provisions:

Evergreen trees, precious trees and deciduous trees transplanted in the growing season must be transplanted with soil balls (soil platforms). The trunk is 20 cm ~25cm in diameter, and the transplanted soil ball is1.5m ~1.8m in diameter; 0.8 meters; The main diameter is 26 cm ~40 cm, and the soil platform should be transplanted. The side length of the soil platform is1.8 m ~ 3 m. Generally, the specifications of soil balls and large wooden boxes are 8 times ~ 10 times of the main diameter, and the height of soil balls is generally about 4/5 of the diameter of soil balls.

Deciduous trees should be transplanted during dormancy, and bare roots should be transplanted into protective soil. The root diameter is 8 times to 10 times of the trunk diameter.

Trees transplanted with soil balls (soil platforms) can cut off broken branches in the process of transplanting after planting; Bare root transplantation should adopt heavy pruning and cut off 1/2~2/3 branches.

Evergreen trees should be trimmed with 1cm~2 cm pegs, and the roots cannot be cut off. When trimming, the cut must be smooth and the cross section should be as narrow as possible. Prune branches more than 2cm, and apply preservatives in time after pruning.

Precious tree species and trees transplanted in the growing season, trunk wrapping measures should be taken.

When digging, the root system should be completely cut off, and the incision should be smooth and not split. When transplanting with soil balls, it is necessary to ensure that the soil balls are intact and the back cover is sealed. After the bare roots are dug up, they should be sprayed with humectant or dipped in mud and wrapped with wet grass. Keep the roots moist.

In the process of excavation, hoisting and transportation, protective measures should be taken for trunks, branches and roots to avoid splitting.

The loading, unloading and transportation of trees must use large mechanical vehicles and operate in strict accordance with safety regulations.

Pay attention to the direction of the main viewing surface when planting.

The size and depth of planting holes should be increased by 60 cm~80 cm and 20 cm~30 cm compared with the diameter of roots or soil balls. The excavated waste soil should be transported away, and the planting soil and humus soil should be put by the pit for later use.