Cultivation techniques of Fraxinus mandshurica bonsai

Fraxinus japonicus belongs to Fraxinus of Meliaceae. Zhongxiang and Jingshan, native to Hubei, are deciduous trees, up to 30 meters high. Young and strong bark is smooth, light gray-green, and middle-aged and old bark has longitudinal dark gray stripes. Branches germinate vigorously and are resistant to pruning. Trees are drought-resistant, moisture-resistant, heat-resistant, like fertilizer, water and sunshine, and can be cultivated in the open field south of Beijing. Suitable for neutral and weakly acidic soils, with PH value of 5-7. Sowing and cutting propagation. Fraxinus mandshurica stumps bought from far places of origin were dug by mountain people in winter and early spring. Local cultivation excavation time can be excavated except from mid-June to mid-August. Generally, the protection measures of mountain people during excavation and transportation are poor. Although this tree species has strong vitality, in order to obtain a higher survival rate, we still need to pay attention to its dehydration in different degrees. First of all, the hurdles should be in place at one time. This kind of tree takes root easily, and it can grow fibrous roots through a cut with a root diameter of 200 mm. Therefore, the root branches that hinder the future pot shape should be sawed off decisively. Secondly, we should absorb enough water. If possible, it is best to put the roots upright in water dissolved with rooting agent (such as rooting powder and vitamin B 12), and the treatment time shall be subject to the instruction manual of rooting agent. Or soak the whole pile in clear water for a day and a night, and then plant it in a sand bed for maintenance. The root burial depth should be more than 20cm, and the old piles and dry piles with dry diameter greater than 20cm should be deepened appropriately. Pile arrangement distance: the spacing between medium-sized piles should be greater than 0.5m, and the spacing between large-sized piles should be greater than1m.. This is conducive to the extension of branches, otherwise the branches cover each other, which is not conducive to growth and pruning operations. Thirdly, after planting, it should be filled with water, so that the sand can be in close contact with the root gap. At ordinary times, the sand bed should be kept moist and the trunk should be watered frequently. If 30%-50% sunshade net is used for protection, the effect will be better. Generally, it will germinate in late spring and early summer. After beginning of autumn in early August, you can take off the sunshade net and let it enjoy the sunshine. From the end of April to the beginning of May, if there are still uncleaned stumps, scrape off their bark with a knife. If the top bark is still emerald green and not yellow, it can be pulled out of the sand bed, soaked in clear water for a day and night, and then planted in a semi-shady and semi-sunny place for maintenance, which can still promote germination and survival.

In order to protect the ecological environment, sowing and cutting propagation are now advocated. Sowing is suitable for large-scale propagation. You can refer to the garden technical data. Bonsai lovers are more likely to propagate by cutting, which is carried out in winter and spring. Use annual robust branches, cut 10cm~ 15cm long before germination, insert them into sand bed, shade them properly, water them frequently, and keep the sand bed moist. It can take root in more than 30 days, and can be transplanted to the field for cultivation in mid-May. It can also be planted in summer and autumn, but it must be shaded to keep the sand bed moist, which is a bit difficult to manage. The new buds germinated in the first year should be treated according to the strength of the sprouting branches of each stump.

For Wang Shu, usually after beginning of autumn in early August, when most branches grow to more than 40cm, the branches are fixed, leaving the branches in line with the modeling direction, leaving 1-2 branches for the clustered branches, and removing the rest. If it is found that there are no branches in the part that needs to be branched, the redundant branches at the lower part of the trunk can be docked with the missing branches. The lower molding branch should be pulled in place with rope or aluminum wire. At this time, it is best not to bind the shape by winding. Due to the rapid thickening of Rhus verniciflua branches, they will be trapped if they are not careful, which will affect the beauty and growth of the first-class branches. According to the planting pile area, urea fertilizer is applied every other week, per square meter 10g-20g, to promote the thickening of new branches. Because ash trees can grow above the daily average temperature of 65438 05 degrees Celsius, if there is enough water, fertilizer and sunshine, the diameter of the flourishing branch base of the new pile can reach more than 20mm when it comes to frost in that year. Therefore, for the terminal branches, the tip should be controlled first (for the rapidly formed commercial piles, the first-grade branches can be cut and the second-grade branches can be cut at the end of the year). Thick branches are needed at the bottom, and other parts are left for growth. In the process of management, it is necessary to observe at any time and find that the redundant branches sprouting at the base of the main branches should be erased in time, otherwise the crazy branches will suddenly grow and consume nutrients in vain, which will affect the growth and thickening of plastic branches. After the frost leaves fall, you can go to the basin. Dig out the pile material from the sand bed, shake off the gravel at the root, cut off the long roots and branches. According to the size of the pile, fill in nutrient soil, and add a fence on the shallow basin to prevent the fibrous roots from exposing the soil surface of the basin. Finally, water adequately and strengthen overwintering management. If the sand bed is not in a hurry, it can be trimmed in winter, and it is better to go to the basin on the eve of spring germination.

For weak branches, although they germinate and sprout, the roots do not grow or grow sparsely, so they should continue to be planted in sand beds until the roots and branches grow vigorously in the next year. Don't rush to prune the pot, it will affect the survival rate. Fraxinus mandshurica is a fast-growing tree species. After one year's cultivation and pruning of basic branches, most branches can be pruned and stored in the next year, except for a few terminal transitional branches, floating branches and drooping branches that are deliberately left long and thick. In the early stage, the first and second branches are tied (pulled), supplemented by pruning, and in the later stage, pruning is the main one, supplemented by pulling branches. Pruning techniques are generally used, pruning from top to bottom to suppress the strong and help the weak. First up and then down: cut the upper branches of the tree first, then cut the middle branches after a while, and then cut the upper branches every few days. For the same branch, cut the upward branch first, and then cut it when the parallel branch grows thicker than the previous branch. Restrain the strong and help the weak: cut the upper strong branches for a few days first, and then cut the weak branches when they grow to a certain thickness. Objective to match the thickness of the branch with its position.

For particularly lush trees, in addition to paying attention to control at ordinary times, you can also pick the leaves and cut them into fixed branches. After the first frost in autumn, when the trees wither due to frost, the branches are bare, which is very conducive to observing the direction of branches (slices), interspersed back and forth, strewn at random, location and shape. At this time, you can carefully trim the branches and tie them. It can be cut in place with scissors, and after it is cut in place, it can be drawn in place with aluminum wire winding and bending; Some branches are too high or the direction is not good, so use aluminum wire or rope to pull them in place. Pay special attention to its opposite branches and frog leg branches: the fixed branches on the trunk should be staggered with the first and second branches, and the opposite branches should be cut off; Frog leg branches can be cut short, or they can be changed into crutches while growing. The management and maintenance of white wax festival bonsai can be summarized by "big water, big fertilizer and big sun": that is, there must be enough water, and wet is better than dry; Large fertilizer: thin fertilizer should be applied frequently during the growth period, once every 5-7 days, so as to facilitate the absorption of trees and avoid the waste of fertilizer solution. Fertilization time is usually carried out in sunny afternoon when the basin soil is dry, and the leaves are washed with water after fertilization. On rainy days, the soil in the basin is wet, and the roots are not breathing well, so it is not easy to absorb after fertilization. Big sun: Even on a hot day, as long as the water keeps up with the high temperature and strong sunshine of 380c-400c, you can see the growth of shoots, and the branches rarely cut themselves, which shows that the adaptability is particularly strong. The simplest way to judge whether they are short of water, fertilizer and sunshine is to observe the germination of their new shoots: when fertilizer, water and sunshine are sufficient, the branches protruding from the top of the tree are thick, and the tender branches and leaves are purple and gradually turn green. When insufficient, the branches are thin and the young leaves are light green.

5~7 days before picking leaves and pruning buds, cake fertilizer and water must be applied once. At the peak of growth, new buds will sprout after three days of strong cutting. After the new buds germinate, cake fertilizer and water should be applied again, and the ratio of water to fertilizer is 8: 1. The fuller the branches, the more pruning times can be increased.

Except for the yellowing of ash leaves caused by long-term sprinkler irrigation in alkaline soil and tap water, no other bacteria invaded. Yellowing disease should be dissolved with ferrous sulfate according to the ratio of 1:400, and then the roots should be irrigated once every other week for 3~5 times in a row. There are two kinds of pests invading ash trees, which have not happened in previous years. One is thrips, the larva is about 1.5mm long, which often harms the new leaves that have been unfolded in spring, making them roll out, making the newly germinated tip shrink into a ball, unable to stretch, and the heart leaves gradually wither. Spray insecticide with dichlorvos 800~ 1500 times, dichlorvos 80% EC 1000~ 1500 times or diving insects 1000~2000 times in time; Or after the larval damage period, when the diseased leaves are removed normally, promote the new leaves to return to normal. The other is bladder scale and red scale. For trees with insufficient sunshine and weak tree potential, most of them suck juice from injured branches. 20% pyrethroid can be sprayed 2000 times in May-June and September-165438+1October, and it is best to kill the pests manually when they just occur.