1. Shortcut
Cutting off or sawing off a part of a branch is called chopping. Due to different degrees of pruning, it can be divided into light pruning (1/5 ~ 1/4 with one branch removed), medium pruning (1/3 ~ 1/2 with one branch removed) and heavy pruning (2/3 ~ 3/4 with one branch removed) In general, the heavier the short cut, the greater the stimulation to the cutting bud, and the stronger the branches that grow from it after germination; When cutting lightly, the cut buds are less stimulated and the branches growing from them are weaker. According to the above performance, if the larger length of lateral branches on the crown does not meet the needs of plastic surgery, but the growth potential of 1 and 2-year-old branches is adjusted by pruning, the pruning principle is just the opposite to that of plastic surgery, with strong branches and weak branches.
Step 2: Get thinner.
Cutting off all the branches at the base is called thinning. There is no obvious stimulating effect on axillary buds on the mother branch near the incision, and the number of branches on the mother branch will not increase because of thinning, but will only decrease.
Thinning work is mainly to remove dense internal branches, create good ventilation and light transmission conditions for the crown, and reduce the occurrence of pests and diseases. At the same time, it can also reduce the number of buds of the whole tree and prevent the new shoots from consuming too much nutrition, so it is beneficial to flower bud differentiation and flowering and fruiting.
Some old stumps, branches with serious pests and diseases, drooping branches, competitive branches, long branches and tillering branches should be thinned, otherwise the tree will decline and even fail to form a sound crown.
Pick a heart
Removing the growing point of the new bud in that year is called "coring". This work is mostly carried out in summer. Tapping can inhibit the elongation of branches and prevent new shoots from extending forward indefinitely, which is beneficial to lignification and early formation of axillary buds.
During the growth of flowers and trees, you can pick your heart many times. After early coring, axillary buds of branches all formed earlier. Most of these premature axillary buds can germinate around beginning of autumn to form secondary branches, which can accelerate the formation of young tree crowns. Generally, it is not advisable to core the secondary branches, otherwise the axillary buds will germinate again and form the tertiary branches when the nutrients are particularly sufficient. Most of these tertiary branches can not be completely lignified before defoliation, and will be freeze-dried after winter, so that some nutrients are wasted.
Step 4: Wipe the buds and hair tips.
Too dense axillary buds will form too dense branchlets, which often make the crown completely closed and affect ventilation and light transmission. This situation is extremely unfavorable to flowering and fruit coloring. For this reason, the over-dense lateral buds and new buds are often erased at the early stage of flower germination, thus reducing the trauma caused by pruning in the future. When cultivating rare evergreen coniferous ornamental trees, buds and tips are often wiped instead of thinning branches to reduce the scars left by pruning.
carve
Cutting off the phloem of branches with a knife is called "cutting", which is one of the auxiliary tasks of pruning. The depth of cutting is based on xylem. Carving some valuable flowers and trees with large patterns can make the flowers and fruits bigger.
The specific method of carving is: in the early stage of flower bud formation, it can be carved at the base of flower branches, and the assimilated nutrients transported downwards stop at the flower-bearing part, which can make flower buds and fruits expand rapidly.
6. Ring peeling
Stripping a circle of bark 3 ~ 5 mm wide around the trunk or large lateral branches with a sharp knife is called "girdling". The purpose is to temporarily prevent the assimilated nutrients produced by leaves from being transported to the roots, which can promote the differentiation of flower buds and prevent falling flowers and fruits.
Circumcision does not hinder the long-term downward transportation of assimilated nutrients, otherwise the root system will stop growing and die. This is because the cortex of girdling is very narrow, and the wound can heal gradually after girdling. However, in the healing process, the sieve tubes that transport assimilated nutrients downward cannot be connected immediately, so that assimilated nutrients are concentrated in the crown for a certain period of time, thus achieving the purpose of promoting flowering and fruiting.
7. Bud thinning
For tufted shrubs, if all the tillering buds germinated in the rhizosphere and axillary buds on the main stem germinate and grow, a large number of branches will grow, and they can all bloom at the top. Because there are too many flower heads, the flowers must be very thin, so they are not pleasing to the eye, and it is difficult to highlight the excellent characteristics of the varieties.
The purpose of bud wiping is to strip off excessive axillary buds, limit the increase of branches and the occurrence of excessive flowers, and make nutrients relatively concentrated. Peeling usually refers to removing the lateral buds and leaving the terminal buds, which can supply the terminal buds with nutrition, make them bloom and ensure the quality of flowers.
8. Sparse flowers and fruits
Among ornamental fruit trees, under the condition of extensive management, the results of some tree species are often more than one year and less than one year. This phenomenon is called "big and small year" or "alternate year fruit". In order to overcome the phenomenon of bearing fruit in different years or alternate years, in addition to strengthening fertilizer and water management, flowers and fruits can be thinned in the new year. In terms of thinning flowers and fruits, thinning flowers can save more nutrition than thinning fruits. But it is quite dangerous to sparse flowers in windy areas in spring. If there is a strong wind after thinning flowers, the number of fruit hanging in that year will be greatly reduced, and thinning young fruits is safer. Most ornamental fruit trees have the habit of natural fruit drop, which is called "physiological fruit drop". This is more serious in the case of malnutrition, so fruit thinning should be carried out after young fruits are set.