The degree of artificial intervention is basically between the first two, but some interventions are large, so they have a certain inhibitory effect on the growth and development of flowers and trees.
According to the biological characteristics of tree species and some requirements of landscaping, pruning workers cut trees into tree shapes that are in harmony with the surrounding environment, usually including cup-shaped, joyful, multi-trunk and multi-trunk, evacuation layered, shrub-shaped, climbing and so on.
(1) Central leadership.
Also known as "uniaxial hollow".
Suitable for single-axis branching and leafy trees.
These trees are all dry, the trunk and middle trunk are always in the axial position of the whole tree, and the subordinate relationship between trunk and branch is very clear.
In plastic surgery, the key is to highlight the axis of trunk, middle trunk and main tip from beginning to end, become a "central leading cadre" and give full play to its "leading role".
There are two kinds of ornamental flowers and trees that adopt the central leadership: one is the senior branch central leadership represented by poplar and ginkgo.
This kind of tree has high branches, plastic belt about 3 meters high and long trunk, which is suitable for street trees.
The method of "cultivating stems first, then fixing branches" is adopted for shaping and pruning, that is, the two ends of the trunk are emphasized to be straight, and some auxiliary branches below the branch point are reserved, and removed year by year, so that the thickness of the crown part always accounts for about 2/3 of the height of the whole plant. When the height reaches the required plastic band, the main branch on the middle trunk should be selected, all branches below the main branch should be removed, and the "axis" of the central leading trunk should be maintained.
The other is the central leadership trunk with low branches, such as cedar and cypress. This kind of tree has low branches and short trunk, but the trunk of the central leadership is obvious and not suitable for street trees.
The method of "cultivating stems while fixing branches" is adopted in plastic pruning, that is, from the initial stage, not only the central main stem, but also the main branch and secondary main branch should be cultivated, and attention should be paid to protecting the lower branches.
It is convenient to maintain and trim the central leadership trunk with correct shape. The key is to maintain the axis of the central leadership trunk, maintain the reasonable azimuth, opening angle and branch spacing of branches at all levels, and give priority to pruning.
(2) Multi-tap stem shape.
Also known as "in-axis dry shape".
Suitable for trees with strong advantages at the top of hinged branches.
The trunk of these trees is obvious, but the dryness is strong first and then weak, the ability of germination and branching is strong, and there are many strong branches. But after 2 ~ 3 years, the advantages of the extended trunk will gradually weaken, similar to the growth potential of the main branch, and it will no longer become the central leadership trunk. In the central part of the tree crown, there are often 3 ~ 5 main branches with small branching angles to replace or grow with the central leadership trunk, and the affiliation is unclear.
Therefore, the main branches must be properly spaced and graded to avoid confusion.
The multi-stem shape at seedling stage should be "dry first and then branch" When the trunk height is not enough and the branches are over-developed, the strong branches must be cut off and the weak branches should be kept as auxiliary branches to make the trunk grow straight. Similarly, the thickness of the crown should always account for about 2/3 of the height of the whole plant.
The plastic belt is generally more than 2 meters. When determining several main branches that reach the plastic belt, if the middle trunk is overdeveloped and affects the growth of the main branches, the extension of the middle trunk should be cut off. If China's trunk line advantage has been lost, it can be allowed to develop or die out naturally.
The culture time needs 4 ~ 5 years, such as camphor tree, Ligustrum lucidum, heather and so on.
The maintenance and pruning of multi-branch trunk is more complicated, especially when it is just finalized, it is in the embryonic stage and tends to be vigorous. It is necessary to remove branches with excessive competition at any time, and at the same time avoid the phenomenon of "partial crown" and "concave crown" due to uneven branches.
The usual practice is that if the strength of branches at the same level is obviously uneven, it is necessary to "remove the strong and leave the weak" to suppress and highlight several main branches in the central part of the crown.
This model is suitable for tree species with strong vitality, which can make the crown more beautiful, advance the flowering period and prolong the life of branchlets, and is most suitable for shaping flowering trees and shade trees.
(3) Evacuation layered shape.
This shaping method has a small tree shape and a low trunk. The plastic belt is generally 80 ~ 120 cm, with a middle trunk, and the main branches are randomly arranged on the thick middle trunk.
When shaping and pruning, as long as the stem height is kept according to the actual needs, the main branches are evenly arranged on the middle trunk, and the useless branches that disturb the tree shape can be cut off one by one.
This kind of tree is actually a natural tree, with little human intervention, which conforms to the natural development law of trees and is very suitable for some small flowering trees.
Two aspects should be paid attention to in the maintenance and pruning of evacuation layered modeling: first, this plastic method itself requires the crown to be transparent, the skeleton branches should not be too many, and the trees should not grow too high to highlight the hierarchy of the whole green space, so the length of the vegetative branches should be properly controlled, properly trimmed and often retracted.
Second, flowering is dominated by short branches, but the growth position of short branches is generally low. Therefore, in addition to properly controlling the number of vegetative branches, it is necessary to select a certain amount of light pruning and cultivate new short branches to gradually improve the flowering position of plants.
4 cup-shaped.
This kind of tree has no hollow trunk, only a fairly high trunk, generally 2.8 ~ 3.2 meters.
The cup-shaped crown needs pruning from young trees, and the culture time is generally more than 4 years.
Emphasis is placed on "cultivating stems first, cutting stems later and fixing branches".
First of all, we should cultivate a trunk with straight ends and determine the height of the trunk according to the needs of the functional environment. After reaching the height of the plastic belt, determine the three main branches and cut off the middle trunk. The included angle between the three main branches is about120, and the included angle between each main branch and the trunk is about 45.
In the future, leave two side branches on each main branch, cut off the extended branches of the main branch after determining the side branches, then leave two branchlets on the side branches, and cut off the extended branches of the side branches after determining the branchlets, so that the side branches at the same level are required to keep the same direction, forming a "three branches, six forks and twelve branches" skeleton branch distribution pattern, that is, forming a cup-shaped crown similar to pseudo-two branches.
The amount of cup-shaped maintenance and pruning is large, and at the same time, it violates the law of tree growth and development, and trees are prone to aging.
⑤ Happy modeling.
This tree shape is an improvement and development of the cup shape. There is no middle trunk, but the trunk is very low, and the plastic band is only 30 ~ 50 cm, which belongs to the method of "fixing the trunk and branches at the same time". Easy to form, can be quickly formed, generally 3 years.
You can pick your heart as early as possible in the seedling stage and naturally choose the main branches that spread around. The main branches are scattered on the trunk, most of which are three, and a few plants also have two or four.
Distribute side branches on the main branches appropriately and extend outward.
At the same time, there is a big flower branch in the middle of the back of the main branch, and there are small and medium flowers branches up and down.
The whole canopy is oblate, the center is properly exposed and the light transmission condition is good.
At present, flowers and trees with weak central axis, lush foliage and large light demand in gardens often use this plastic way, such as plum blossom, peach and pomegranate.
6 dry form without leadership.
Also known as "hollow".
It is suitable for trees with weak top dominance of joint branches or false two branches.
This kind of trunk is the weakest and has a trunk, but it is often easy to bend or branch at the lower part, and the trunk in the middle will soon lose its advantage.
Because of weak germination ability, strong branching ability, few strong branches and large branching angle, some branches with high branching point and good orientation are very valuable, so we should pay attention to choosing and staying.
Note that there are at least three skeleton branches that make up the crown, so that they can be evenly distributed, and the branch spacing should be widened to be natural.
The form of leaderless trunk in seedling stage should emphasize "cultivating dry first, then fixing branches"
In particular, some tree species with obviously weak dryness are difficult to keep dry, so the method of turning back in the first year can be adopted to lay a good foundation for cultivating straight stems.
The plastic belt is generally more than 2 meters. When the height of plastic belt is not reached, the auxiliary branches below the branch point should be retained and eliminated year by year.
Attention should be paid to the selection and retention of suitable main branches that meet the requirements of plastic belt during plastic surgery.
When the skeleton branch is completed, immediately cut off the extension of the middle trunk.
Due to the small number of branches of most tree species, it is more difficult to shape leaderless trunks than the above two methods, and it usually takes 4 ~ 5 years to cultivate, such as Albizzia julibrissin and Sapindus mukoraiensis.
The maintenance and pruning of leaderless trunk shape is relatively simple, and only need to pay attention to the symmetry and hierarchy of each part of the crown, and the pruning amount is generally small.
⑦ Multi-branch closed heart shape.
Suitable for small flowering trees or shrubs with more branches and fuller crowns.
Emphasis is placed on "drying first, then fixing branches", but the height of trunk is arbitrary, and the drying time varies with the height of plastic belt.
Shrub-type forming is the fastest, generally only 2 years; The higher the trunk, the slower the formation, which takes 3 ~ 4 years.
Because the middle trunk is generally underdeveloped, it can be retained or removed manually after it grows to a certain stage (such as the emergence of secondary main branches).
This kind of tree species often has many branches, strong branching ability and unclear branching order, so it is mainly sparse and dense branches, and the branch spacing can be appropriately smaller. Full crown, no attention to hierarchy, low plastic requirements, and correct tree shape, such as pomegranate, hibiscus, osmanthus, camellia and so on.
8 Shrubby.
This plastic method is quite similar to the multi-stem shape or multi-stem shape, except that the stem is short or not, and the remaining branches are many and clustered.
This shape is mostly used for shrubs with strong germination, many branches, long branches and small trees.
According to the morphological characteristics of shrubs, shrub morphology can be divided into two categories: one is tufted shrub morphology.
Some ornamental flowers and trees, such as Yingchun, are clustered shrubs with unclear branches and plastic belts close to the ground. Pick the core as early as possible at the seedling stage, so as to increase the number of branches and form quickly.
Maintenance and pruning is also very simple, just cut off redundant branches, too dense branches, aging branches and other useless miscellaneous branches, and always pay attention to the renewal of branches.
The other is a skeleton shrub.
Some ornamental flowers and trees, such as hydrangea and brocade, are shrubs or even trees, and have no fixed geometric shape, but for the sake of nature, this shaping method is adopted.
At the seedling stage, the method of "fixing the stems and branches at the same time" was adopted, and the plastic belt was about 20 cm, leaving several main branches as skeleton branches. Skeleton branches should be relatively stable, can be updated in time, and the posture is not round, natural and beautiful.
This shaping method requires high maintenance and pruning, and it needs to be reshaped every year, mainly to keep the branches naturally distributed and stretched, restrain strong branches, especially long white branches, cultivate flower branches, update old branches in time, and avoid tree rigidity and disorderly branches.
Pet-name ruby climbing.
This is a common shaping method for lianas.
During plastic surgery, a solid scaffold, gallery and pavilion should be built first, then vines should be planted, and induced and pruned according to their growth and development habits. The shape depends on their supporting form.
There are many different application methods, such as scaffolding, balcony, fence, attached wall, hanging and so on.
Because vine flowers and trees have no fixed tree shape, their shaping should change according to different application forms, while maintenance and pruning should depend on the growth and development of specific tree species.