Hongfeng: native to the east coast of the United States, mainly from the northern United States and most parts of Canada. It is a deciduous tree. It grows rapidly, with adult tree height 12- 18m and crown width 12m, which can adapt to the growth of various soil types. In bloom in spring, the flowers are red. Because of its bright colors and neat crown in autumn, it is widely used in parks, communities and streets. It can be used as both landscaping and street trees, and is deeply loved by people. It is one of the ideal rare tree species introduced to beautify and green urban gardens in recent years. It is also the only colorful tree species that can be used as street trees.

This tree species grows rapidly, which is the fastest growing variety among all red maple varieties. There are many improved gardening varieties of American red maple, such as Acer truncatum, October Glory, Sunset Red Maple, Sunset Red, Autumn Fire, Amsland, Beimu and so on.

Growth habit

American red maple has strong adaptability, cold tolerance, drought tolerance and moisture tolerance. Acidic to neutral soil makes autumn colors brighter. It has strong resistance to harmful gases, especially to chlorine, and can be used as an anti-pollution greening tree species. The performance of autumn leaves of American Acer truncatum mainly depends on environmental factors, such as planting in high altitude areas or mountainous areas, large temperature difference between day and night, good air humidity and good performance. If planted in urban areas, it is relatively poor due to the influence of heat island effect. If planted in high latitudes in the north, it will perform well in autumn, on the contrary, it will be relatively poor in low latitudes in the south. The performance of the same American red maple variety will be very different even if the planting location is changed.

breeding method

There are two main ways of reproduction of American red maple, sexual reproduction and asexual reproduction.

Sexual reproduction is generally through seed reproduction. In the process of sexual reproduction, genes will recombine and mutate, that is to say, the characteristics of American red maple seedlings obtained by seed reproduction are unstable, which leads to the instability of American red maple when it changes color, and may not change color, which may be different from the leaf color of its parents.

Asexual propagation is generally cultivated by cutting seedling and tissue culture. The sapling directly inherits the characteristics of the female parent and will not mutate. In other words, what color the leaves of the mother plant are, what color the American red maple seedlings will show. The discoloration of American red maple seedlings obtained by asexual propagation will be very stable.

transplant

According to the diameter of rootstock and scion and the grafting method, the classification is different. What are the grafting methods of American red maple? There are mainly the following grafting methods:

1, branch grafting can be divided into cutting, splitting, tongue grafting, skin grafting, abutment and other methods;

2. Bud grafting can be divided into T-shaped bud grafting, tubular bud grafting and square bud grafting. An American gardening expert adopted the method of taking buds with one knife, and the effect was also very satisfactory.

3. In addition, there are methods such as double rootstock grafting and root budding.

Either way, the cambium of rootstock and scion should be aligned first, so that the callus produced by cambium of both sides can be formed and healed together as soon as possible, and various necessary tissues can be differentiated to ensure nutrient transportation and scion hair. In order to align the cambium of rootstock and scion, it is necessary to make the incision smooth and minimize the damage, and the incision slope should be consistent, preferably with the same diameter, so as to facilitate the anastomosis of rootstock and scion; When the rootstock and scion are ready, they should be grafted quickly. At the same time, the sections of the rootstock and scion should be close together, and then wrapped tightly to reduce water loss and pollution, so as to avoid looseness and affect callus healing.

In a word, the key to the survival of grafting is that the cambium of rootstock and scion is aligned, close to each other and not destroyed. Bagging or dressing after grafting is also a necessary condition to ensure the formation of callus and differentiation of other tissues. Therefore, good grafting techniques and tools are needed.

Select seedlings cultivated with seeds. First, the cost of American red maple seedlings cultivated in this way is lower. Cutting seedlings cost too much. Secondly, because of the variability of American red maple seedlings, it is possible to get seedlings that can better adapt to this area. Any seed sowing seedlings will have certain variation, but this variation does not necessarily mean worse, but it may also be better. As long as the seedlings are carefully screened, it is entirely possible to select some American red maple seedlings with good quality. Third, you can choose different provenances to plant in different areas. American red maple is mainly distributed in North America, parts of Canada and all parts of the United States. The adaptability of different provenances varies greatly. Choosing provenances with similar climatic conditions will undoubtedly improve the introduction success rate of American red maple.

sow seeds

Sowing in spring

Soak seeds. Generally, the wings of seeds should be ground off half a month before sowing in Tomb-Sweeping Day, and the seeds of American red maple should be soaked in warm water 12 hours.

Sand storage: Acer truncatum seeds have been tested many times, and low temperature sand storage is not needed. Choose coarse river sand with good permeability, and mix the sand and seeds according to the ratio of body: 3:/kloc-0:, and the humidity of the sand is-the hand agent is loose when caking. After mixing, put the mixture of seeds and sand into the room.

Preparation of seedbed before sowing: Deeply plough topsoil and break it, with ridge width of 1.5m and deep ditching.

Sowing: Generally speaking, the seeds of American red maple begin to germinate in 15-20 days, and all seeds can be sown when the germination reaches 20% (you can also pick out the germinated seeds first). Sow 3 kilograms of American red maple seeds per mu, open a furrow with a depth of 10 cm and a width of 20 cm on the completed ridge, and evenly spread the seeds and sand on the furrow seeds. (total control)

Covering the soil to support the small arch shed: after sowing, cover the seeds with a layer of wet fine soil. The covering soil should not be too thick, generally 0.5- 1 cm, which will affect germination. Support a plastic shed, and then support a sunshade arch shed on the plastic shed. Pay attention to the plastic arch shed below and the sun protection arch shed above. The distance between the two arches should be more than 20 cm to keep the effect of ventilation and cooling.

Daily maintenance: 1 month after sowing is the key period for American red maple to germinate. Always observe and maintain the temperature and humidity in the arch shed, and put your hand into the membrane arch shed to show that it is not hot. If it is found that the temperature is too high, it should be ventilated immediately and sprayed with water at both ends of the membrane arch shed to cool down. When the seedlings grow to 5- 10 cm, remove the membrane arch shed. The sunshade arch shed will remain. After the seedlings grow to 20-30 cm, open the sunshade curtain in the morning and evening and cover it at noon. After 2 weeks, the sunscreen will be completely uncovered.

Weeding with water and fertilizer: foliar fertilizer or a small amount of urea can be used after the seedlings grow to 10 cm. Remember that fertilization should follow the method of small amount and multiple times, and not excessive at one time to prevent seedling burning. At present, there is no effective herbicide that is harmless to American red maple seedlings, and artificial weeding is generally used.

Sow in autumn

Generally, the germination rate of autumn sowing is not high, so it is recommended not to sow in autumn unless the seedlings are very nervous. American red maple can be sown in autumn theoretically, but after years of practice, autumn sowing is not ideal, and newly picked seeds may not be dormant, so autumn sowing and spring sowing are different in the following aspects.

Sand storage: Autumn sowing means that the local temperature is generally in mid-August, seeds are mixed with sand according to the method of spring sowing, and the mixture is stored in a low-temperature refrigerator at 3-5 degrees Celsius for one month (not frozen).

Because of the high temperature in autumn, there is no need for a small film shed after sowing in the field, so it can be covered with a sunscreen net.

Seedling pruning technology

Before planting American red maple seedlings, the roots and crown of seedlings should be trimmed, and splitting, diseases and insect pests and excessive roots must be cut off to ensure the original natural posture of American red maple seedlings.

If the incision is larger than 2 cm, it must be embalmed.

The height of street trees should be 3 meters, and the American red maple should be more than 2.5 meters. All branches below the first branch point should be cut off, and branches above the branch point should be thinned or chopped as appropriate.

Tall deciduous trees, such as American red maple, should maintain their original tree shape and be thinned appropriately. The main lateral branches should be cut short on the strong buds, and 1/5- 1/3 branches should be cut off.

Evergreen conifers should not be pruned, only pests, dead branches, weak branches, over-dense branches, drooping branches and mechanically worn branches can be pruned.

Evergreen broad-leaved trees basically keep the tree shape and shrink the crown. In normal season, the total crown is 1/3-3/5, the main skeleton is reserved, the peripheral branches are cut off, the internal branches are thinned out, and most leaves are removed.

Flower shrubs are mainly sparse old branches, supplemented by short cuts; Hedge and ball pruning must be neat and consistent, straight lines, beautiful shape, smooth incision and good gardening effect.

Climbing vines can cut off dead vines and long vines, stagger branches and grow branches horizontally.

6 cultivation technology editor

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. Good management can make the growth rate of Hongfeng 1 year exceed 2 cm. 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. [4]

7 trim plastic editing

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 new shoots extend to the left or right, 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.

8 pest control editor

The pests and diseases of American red maple are mainly caused by longicorn beetles, mainly black mites and Anoplophora glabripennis. Timely treatment after discovery will not affect trees.

Black mite

When greening, increase the spacing between trees, generally about 5 meters, which can prevent larvae from spreading among trees.

Pay attention to the use of nitrogen, phosphorus and potassium fertilizer in combination with pruning, so that red maple trees can grow vigorously and resist pests and diseases.

Before the trees germinate in early spring, spray the trunk with 100 times of oil emulsion or 50- 100 times of crystal sulfur mixture to eliminate overwintering eggs.

When the damage is serious, use triazole tin or 1500-2000 times solution to sweep mites and 2000 times solution for white mites.

long-horned beetle

Anoplophora glabripennis: about 35 mm long, black, metallic, leathery, with white spots and black tentacles. Mainly lay eggs on the trunk, bite an inverted T-shaped mouth when laying eggs, which are produced inside the bark and the eggs are milky white. Larvae is 50 mm long, milky white, and the chest back plate is yellow-brown. After more than a month, they enter the xylem to feed. Activities begin in March every year, pupate in mid-May, and adults appear in June-July.

Control measures of Anoplophora glabripennis;

Strengthen the cultivation management of trees, increase the resilience of trees, pay attention to pruning and cut off diseased branches in time.

Capturing adults and larvae manually, using adults to move between trunks after emergence, and hitting the spawning trough with a cone at the spawning place are all effective preventive measures.

Drug control, using polyester drugs, such as spraying beta-cypermethrin 1500 times solution on the trunk, or injecting 800 times solution of this medicine into the drainage hole of longicorn beetles to control longicorn beetles.