Select seeds

Hongfeng seedling market is in an extremely chaotic state, so it is very important to choose a reliable seedling company to buy good varieties, otherwise it will be wiped out. There are no fewer than 30 varieties of American red maple in China, which is difficult to distinguish. Especially at seedling stage, it can only be distinguished from leaves. People who have planted Hongfeng for 65,438+00 years can't tell 65,438+000% of the varieties from the leaves alone, let alone ordinary growers. At the same time, most American red maple will have red leaves at seedling stage, which makes variety identification more confusing. You must choose a company with a brand and high quality provenance to buy seedlings.

land

Sandy loam. This kind of soil is ideal.

Black clay. This kind of soil is generally caused by rice planting in the past, with poor air permeability but high fertility. It's best to plough deeply before Chinese New Year. Frozen for one winter, it became brittle in the next spring, and the soil structure was greatly improved.

The soil is alkaline. American red maple likes acidic soil, but slightly alkaline soil has little effect, but in order to make it grow better, ferrous sulfate can be used to neutralize alkaline soil to make it neutral to acidic.

The soil layer is very thin. Because Acer truncatum Bunge is a shallow-rooted tree species, the thickness of 50 cm soil layer can meet the conditions for big trees to hit the soil ball. If the soil layer is less than 50 cm, you can make a big ridge and plant it on it. ?

operate

Hongfeng is a fast-growing tree species, and its growth rate depends entirely on water and fertilizer management. The growth rate of Hongfeng 1 can be more than 2 cm by using Trim special water-soluble fertilizer and good management. The cultivation of Hongfeng in the United States has been refined to different stages of seedlings and different water and fertilizer control in different periods (such as infant milk powder formula for different age groups). Doubletree Hotel customers will provide management manuals free of charge. ?

Dressing and shaping

Pruning and thinning

This paper mainly prunes overgrown branches (common in middle-aged street trees and street trees that have lost their top branches due to accidental injuries), cross branches, unhealthy branches, diseased branches, dead branches and interfering branches to meet the needs of modeling. The key point is to grasp the following three "degrees": length, strength and angle.

Moderate thinning: the development of seedling crown is basically balanced, and the plastic surgery is mainly moderate thinning. Sparse the vertical and overgrown branches on the trunk of seedlings, as well as the opposite branches, whorled branches and too dense cross branches, so as not to destroy the normal crown shape and trunk shape. It is also necessary to remove branches that grow weakly and have pests and diseases in the crown.

Restrain the strong and help the weak: the uneven development of seedling crown is mainly to restrain the strong and help the weak in the transformation. In winter, vigorous branches and upright branches can be properly thinned, the opening angle of lateral branches can be increased, the head can be changed with back branches, and weak buds or weak branches can be left when pruning branches, so as to weaken the growth of excessively vigorous lateral branches. For weak lateral branches, we should promote their growth, remove dying and dead branches, reduce the opening angle of lateral branches, replace the head with upright branches, and take appropriate short cutting and cutting to leave full buds to promote the growth of new shoots of American red maple.

Control the growth of large lateral branches: American red maple should control the growth of large lateral branches regardless of the balanced development of seedling crown. If the diameter of the base of the big lateral branch exceeds 1/3 of the diameter of the trunk of the seedling, the big lateral branch should be re-cut (including thinning and re-cutting, etc. ) to inhibit the growth of * * *. American red maple was trimmed into a beautiful crown.

Adjust the extension direction of lateral branches: the general growth direction indicates the extension direction of later branches. Therefore, the growth direction of new shoots can be controlled by keeping the orientation of cutting buds during short cutting. For example, in order to expand the spreading angle of the lateral branches, the downward buds on the outside of the branches can be reserved as cutting buds; In order to make the lateral branches develop in the vertical direction, the buds growing upward on the inner side of the branches can be reserved as cutting buds; In order to make the new shoots extend to the left or right, the cuttings should grow to the left or right. In order to enlarge the opening angle of lateral branches, if the method of simply cutting lateral buds can't achieve the goal, the method of pushing out inner buds can be adopted, that is, the second bud under the cuttings is selected as the head of lateral branches after winter, and the inner buds remain in the cuttings. After cutting in the second year, the first branch stands upright and the second branch leans outward. In winter, the first branch can be cut off. If there are many branches, leave the 1 th branch under the cutting door. When the secondary branches are all upright, the tertiary buds can be cultivated as extension branches, and the 1 secondary branches and secondary branches can be cut off in winter. This method is called double-bud kick. In addition, in the summer when the branches grow vigorously, measures such as binding and pulling can be adopted to change the position and extension direction of the lateral branches. After the end of the growth period, the branches are lignified, basically shaped, and can be loosened after being tied.

plastic repair

According to the different growth conditions of each street tree, it is necessary to repair and reshape individual street trees, which mainly includes the following work: germination, grafting, binding and simulated repair.

Pillar support

Mainly to support and protect the newly planted street trees, which can be carried out according to the conventional triangular support method; The pits of new and old street trees can be protected by lawn or cast iron and precast cement bricks. The fourth is pest control. Whitening in winter is a daily work, mainly for beauty, and it is also important to prevent and control pests and diseases.

Crown height ratio

The purpose of determining the ratio of crown height (the ratio of crown length to seedling height) is to maintain proper crown width and leaf area on the one hand to ensure the vigorous growth of seedlings; On the other hand, it is necessary to gradually eliminate the lateral branches at the base of seedling crown during the growth process, so as to ensure the continuous growth of trunk height, reach the required fixed trunk height as soon as possible, and promote the growth of trunk. The value of crown height ratio depends on different tree species, ages and crown width development of seedlings. Generally, the ratio of crown width of negative tree species to evergreen tree species is large; For positive species, deciduous broad-leaved species and fast-growing species, the crown width ratio can be smaller. Landscape trees, especially street trees planted around them, are mostly fast-growing deciduous broad-leaved trees, such as poplar, paulownia, elm, Sophora japonica, Robinia pseudoacacia, Platanus acerifolia and Toona sinensis. For these trees, when the height reaches 3-4 meters, the ratio of crown width to height should be kept at about 3/4. When the height of seedlings is 5-6 meters, the ratio of crown height should be kept at about 2/3, and when the height of seedlings is more than 7 meters, the ratio of crown height should be kept at about 1/2. After the height of the trunk reaches about 2 meters, the large lateral branches and a proper amount of small lateral branches at the base of the seedling crown can be pruned once every 3-4 years. The height of seedlings is increasing year by year, so it is necessary to gradually prune the branches planted at the base of seedlings to keep the trunk growing and reach a fixed height. When the trunk reaches a fixed stem height, the lateral branches of the above parts may not be pruned, but the crown of the seedling can be enlarged as much as possible, the nutritional area can be increased, and the height and thickness of the seedling can be promoted. ?