China has Dalian in the north, Xi in the northwest, Cheng Kun in the southwest and Guangzhou in the south. About 20 provinces and autonomous regions grow well.
It has heterosis, vigorous growth, fast branching, many branches, strong regeneration ability, large crown, strong branches and leaves, pollution resistance, and is suitable for street trees and shade trees. Platanus acerifolia is a deciduous tree with a height of 30 meters. The bark is smooth, axially branched and the crown is spherical. The bud is wrapped under the petiole and exposed in winter after defoliation.
Leaf blade palmately 5-lobed, stellate pubescent when young.
Flowering in April-May and fruit ripening in June165438+1October.
Platanus acerifolia is a positive tree species and is not tolerant to shade.
Cold-tolerant, suitable for planting in areas with annual average temperature 13 ~ 20℃ and frost-free period of more than 200 days.
Adapt to all kinds of soil.
Belonging to shallow-rooted tree species, crown growth should be controlled to prevent the wind from blowing down. Platanus acerifolia grows once a year, with a long growth period and a large amount of growth, but generally there are no secondary branches.
It germinates in late March, spreads leaves in the first half of April, and scatters nuts in May. Growth peaked from June to August and stopped in mid-September. It ripens in June 5438+ 10, and leaves in mid-February 65438+February, with an annual leaf period of about 250 days. It is very suitable to be a street tree, ranking first among the "four major street trees in the world".
Platanus acerifolia, as a street tree, generally adopts cup-shaped modeling method. It is not difficult to shape a cup, but it takes a long time, usually more than 5 years to shape it.
After planting at seedling stage, turn around uniformly. In the second spring, strong and straight shoots were selected for trunk culture. Before coming to the plastic belt, the strong branches are mainly removed and the weak branches are kept as auxiliary branches.
After reaching the plastic belt (at least 3 years), select 3 (or more) evenly distributed main branches and cut off the upper and middle branches of the plastic belt to expose the crown. The azimuth angle of main branches is120 (90 for four branches), and the opening angle is generally 45 ~ 60.
In the fourth year, two (or more) lateral branches are selected from the base of the main branch 40 ~ 50 cm, and the extension line of the main branch is cut off, so that all the auxiliary branches below the plastic belt are thinned. In the fifth year, two (or more) small side branches were selected from each side branch at a distance of 40 ~ 50 cm from the branch base, and the extension of the side branches was cut off.
The lateral branches and small lateral branches all develop in the direction of oblique space around, and the branching angle is 30 ~ 45, which continuously expands the crown.
In this way, the main branch, side branch and small side branch are determined, and the branch morphology of 12 fork with 3 main branches and 6 branches is formed, and the cup shape is very complete.
After that, the branches of the current year are cut short and left 15 ~ 20 cm during the dormant period every year, which is called small folding, so that the position of sprouting branches is improved year by year. When the top of the branch will touch the line, it will be retracted to reduce the height. This is called a big turn-back. By rotating alternately back and forth, the crown is kept at a certain height. Plastic surgery, maintenance and pruning are mainly carried out during the winter dormancy period, and there are many short cuts and head changes. Moreover, Platanus acerifolia needs a lot of thinning because of its strong germination and branching ability, so as to cut off pests, cross branches, overlapping branches and upright branches in time.
In spring and summer, buds should be peeled and tillered regularly (except twigs).
If the road is not very wide and there are no wires passing through it, you can use the happy crown. After planting, 4 ~ 6 main branches are selected, and after short cutting every winter, 1 branch slightly higher than the syncline growth is selected as the extension branch of the main branch, so that the crown rises year by year and a hollow oval crown can be formed.
When pruning, strong branches and weak branches should be cut off to make the crown develop in a balanced way. In addition, Platanus acerifolia can be planted not only as street trees, but also as shade trees and solitary trees.
When planted as shade trees and solitary trees, the natural crown shape is suitable.
In winter, the top of the central main branch is cut off 1/3, and then the branches with certain intervals on the central main branch are cut short, leaving outward buds under the incision to slow down the growth of the tree.
The lateral branches should be gradually shortened from bottom to top.
Overlapping branches, weak branches and pest branches can be cut off at one time.
When pruning in summer, attention should be paid to inhibiting the upright branches on the side branches to ensure the high growth of the central main branch.
The winter cutting in the second year is the same as that in the previous year, but the direction of bud retention after short cutting of the extension branches of the central main branch is opposite to that in the first year to form a straighter trunk.
In the future, with the growth of tree height and the expansion of crown, the lowest 1 ~ 2 branches can be cut off, and after several years of repeated pruning, they will grow naturally.