Planting techniques of Robinia pseudoacacia

Sophora pseudoacacia, also known as Sophora japonica, Sophora pseudoacacia, Sophora pseudoacacia, etc., is a leguminous tree native to China, and is now widely cultivated in north and south provinces, especially in North China and the Loess Plateau, especially in Japan and Vietnam. North Korea and wild, Europe, America are introduced, with high planting value, let's take a look at the planting technology of Robinia pseudoacacia!

Planting environment of Robinia pseudoacacia

Robinia pseudoacacia likes light but is slightly shade-tolerant, can adapt to colder climate, has deep and developed roots, and has lax requirements on soil. It can grow normally in acidic to calcareous and mild saline-alkali soil, even when the salt content is about 0.15%. It is resistant to wind, drought and barren, especially adapting to adverse environmental conditions such as urban soil consolidation, but it grows poorly in low-lying stagnant water and has strong resistance to pollution such as sulfur dioxide and soot. It grows faster when young, and then grows at a medium speed, and its life is very long. the old tree is easy to become hollow, but the life span of latent buds is long, which is beneficial to crown renewal.

Root-burying propagation of Robinia pseudoacacia

1. Seed preparation: the root of Robinia pseudoacacia can be introduced after defoliation, and it can be buried and preserved in sandy soil before planting, so as to control the humidity of sandy soil, so that the root segment should not be dehydrated and withered, and the humidity should not be too heavy and moldy and rotten.

2. Soil preparation: the sandy loam soil with deep soil layer, flat terrain, convenient irrigation and drainage and no infection source of diseases and insect pests is the best for seedling breeding. 2500 kg of livestock and poultry manure or 50 kg of phosphate fertilizer and diammonium fertilizer were applied every 667m2, and insecticides such as carbofuran were used to kill underground pests. The ground should be turned over deeply, refined and raked flat, and the width of the bed should be about 1 meter.

3. Seedling raising: the seedling time is the first and middle of March in the south and the last ten days of March to the first ten days of April in the north. The smooth root segment with a diameter of 5 mm and no signs of diseases and insect pests of 1 ~ 2 years old was selected and cut into 5 cm long and 7 cm long. Open the ditch along the border, the ditch distance is 50 cm, the depth is 5 cm, and then put the root segment in the ditch with a plant distance of 30 cm, cover the fine sandy soil, pour through the fixed root water, cover the plastic film, and the seedlings can emerge in about a month.

Cutting Propagation of Robinia pseudoacacia

The main results are as follows: 1. Cutting time: cutting time is the same as root-burying seedling, or earlier.

2. Cuttings selection: select woody branches with a diameter of 8mm and 20mm, cut into cuttings 15cm long, the upper incision is cut flat, 1cm away from the bud package, the lower incision is cut into an oblique mouth of 45 degrees, 5mm away from the bud package, and 50 roots are divided into a bundle of upper and lower ends. Soak the lower end with 50 mg / kg rooting powder solution for 3 hours, then remove and set aside.

3. Cutting method: the soil preparation requirements are the same as before, according to the plant spacing of 20 cm × 40 cm, the branches are inserted into the soil at an inclination angle of 45 degrees, and the plastic film is covered along the border.

Seed propagation of Robinia pseudoacacia

The main results are as follows: 1. seedling site selection: the seedling land of Robinia pseudoacacia should choose loam or sandy loam with flat terrain, good drainage and irrigation conditions, fertile soil and deep soil layer. It can adapt to neutral, calcareous and slightly acidic soil, and the electric energy grows normally on mild saline-alkali soil (salt content is about 0.15%), but the growth of dry, barren and low-lying waterlogged nursery is poor.

2. Seed treatment

① soaking method: soak the seeds in 80 ℃ water, stir continuously until the water temperature drops below 45 ℃, place for 24 hours, take out the swollen seeds. The unswollen seeds were repeated for 2 or 3 times to make them expand. Cover the inflated seeds with a wet cloth or grass curtain to sprout. After 1.5 to 2 days, about 20% of the seeds can be germinated.

② sand storage method: the seeds are generally stored 10-15 days before sowing. Before storing the sand, soak the seeds in water for 24 hours so that the water content of the sand reaches 60%, that is, it is held in a ball and is about to be dispersed. Mix the seed sand at a volume ratio of 1:3, put it into a hole dug in advance, and then cover it with plastic sheeting. During sand storage, turn it once a day and keep it moist. 50% of the seeds can be sown when they germinate.

3. Sowing method: the sowing time is generally spring sowing, and Zhuozhou is generally suitable for sowing in the first and middle of April. The sowing rate is 10kg to 12kg per mu. Ridge sowing or two ways can be used. When sowing ridges, the distance between ridges is 70 cm 80 cm, the width at the bottom of the ridge is 40 cm 50 cm, the width of the ridge is about 30 cm, the height is 15 cm 20 cm, the sowing width is 10 cm, and the cover is 1.5 cm 2 cm. It can also be made without ridging, with a row spacing of 60 to 70 centimeters and a sowing width of 5 centimeters. Suppressed after sowing, so that the seeds are closely combined with the soil, and can be covered with film when conditions are available.

Planting Management of Robinia pseudoacacia

The main results are as follows: 1. Timely seedling setting: seedlings usually start to emerge at 7-10 days after sowing, and all at 10-15 days. The plastic mulching plot should remove the plastic film when the seedlings grow 2 or 3 true leaves. When the seedling height is 15 cm, the seedling spacing is 10 cm and 15 cm, and the number of seedlings retained is about 8000 plants per mu.

2. Transplanting management: used for greening seedlings, it usually takes 3 to 4 years to come out of the nursery. Because the buds at the top of the seedlings are dense, the question distance is short, and the trunk is very easy to bend, the annual seedlings will be transplanted according to the plant spacing of 40cm to 50cm and the row spacing to 70cm in the following spring, and the trunk can be cut off at 3cm from the ground after planting. Because the locust tree has sprouting power, it is easy to sprout a large number of buds after truncation. When the sprouting shoots grow to about 20 cm, a strong branch upright and upward is selected as the trunk and the rest of the branches are wiped out. In the future, we should pay attention to removing the tillers and removing the side at any time, and temporarily retain the weak lateral branches in the upper, middle and lower parts of the trunk, which is beneficial to prevent the bending of the trunk. In this way, the seedling height can reach more than 3 meters in the following year.

3. Fertilizer and water management: the watering times of Robinia pseudoacacia seedlings should be determined according to climatic conditions, soil texture and other factors. In general, watering 2: 3 water after emergence to before the rainy season, watering the nursery land with frozen water once before freezing, and timely drainage in case of waterlogging. Before sowing, about 3000 kg of base fertilizer (mainly organic fertilizer or circle fertilizer) was applied per mu of seedling land. In the first ten days of June, the available nitrogen fertilizer can be applied by 8kg / mu combined with watering, and urea should be applied from July to August, the amount of fertilizer should be about 30 kg / mu. After September, there will be no more watering and fertilization to promote the Lignification of seedlings.

4. Shaping and pruning: according to the need, it can be shaped and trimmed into three kinds of tree shapes: natural happy shape, cup shape and natural shaft trunk shape. The natural happy shape means that when the trunk is more than 3 meters long, 3 to 4 branches with strong growth and proper angle are selected as the main branches, and the lateral branches and sprouts below the main branches are removed in time, and the main branches are cut short when cutting in winter, leaving 50-60 cm, to promote the growth of auxiliary shoots, so as to form a small crown, that is, the cup shape is the same as the natural happy shape, leaving 3 main branches as well as natural happy shape, and 2 short lateral branches are selected on each main branch during winter cutting. Six branchlets are formed, and the coring is carried out in summer to control their growth, and two short shears are selected on the branchlets in the following winter cutting to form a cup shape of "3 strands, 6 weights and 12 branches". The natural hinge trunk shape means that after keeping the main branch, as long as the strong terminal bud and erect bud are kept in the future pruning, the tree crown will continue to expand.

5. Pest control: the main diseases of Robinia pseudoacacia are powdery mildew, canker and rot. 70% methyl topiramate wettable powder 800 × 800 or 50% thiophanate wettable powder 600 × 800 can be sprayed to control the main insect pests are locust aphid, locust inchworm, armyworm, American white moth and so on. The mixture of 10% imidacloprid wettable powder N2000 times and 4.5% cypermethrin EC 1500 times or 2.0% N-vermectin EC 3000 times can be selected for control. The weeding in Sophora japonica nursery is mainly in the seedling field of the same year. Manual removal or chemical herbicides can be taken. When using chemical herbicides, we must be careful not to spray the chemicals on the tree trunks.