Growth habit of Rhus typhina

Rhubarb is a small deciduous tree, belonging to Rhus vernicifera. Odd pinnate compound leaves alternate, oblong to lanceolate. The erect panicle is terminal and the spike is bright red. The fruit is oblate, with red bristles and dense clusters. Name of basic information: Rhus typhina Nutt, Rhus typhina Nutt, Rhus species, Rhus species, Canada Distribution: It is native to North America and often grows on open sand or gravel soil. Small deciduous trees were introduced in China in 1959, and more than 20 provinces and cities such as Shandong, Hebei, Shanxi, Shaanxi, Ningxia and Shanghai tried to plant small deciduous trees with good morphological characteristics, reaching 12m. Bud branchlets near flowering stems are densely covered with gray hairs. Odd pinnate compound leaves, lobules 1~23, serrated, oblong to lanceolate, tapering at the apex, rounded or broadly wedge-shaped at the base, dark green at the top, pale at the bottom, with fine hairs on both sides, which fall off when old. Inflorescence terminal, densely hairy, light green flowers, female flower style with red bristles. Drupe is red, the style is persistent, and the dense growth habit is fond of light. Cold tolerance, strong adaptability to soil, drought resistance, barren resistance, water resistance, humidity resistance and saline-alkali resistance. Developed root system and strong tillering ability, 30~50 tillering plants can germinate within four years. The shallow-rooted, fast-growing, short-lived and garden torch tree is an excellent tree species in autumn scenery, with red spikes like torches and bright red autumn leaves. It should be planted in the corners of slopes and parks to attract birds to feed and increase the interest of gardens. It is also a good tree species for dike consolidation, sand consolidation and soil and water conservation. In the application, it should be noted that its roots and tillers are extremely scattered, so it is not suitable to be matched with other tree species, otherwise it will be covered by the torch tree soon-[hide]1description of torch tree 2 main purposes 3 greening purposes 4 development value 5 propagation methods 6 clonal ramets and Vitex negundo 7 matters needing attention. Description of torch tree Torch tree Torch tree is a positive tree species, and its title is Ilex, commonly known as Lycium chinense. Because of its bright red fruit and tree-like torch light, it is called "Torch Tree". Torch tree presents three colors every year: white flowers in spring, green leaves and fruits in summer, and red fruits in autumn and winter. This is a very precious landscape plant. The flowering period is May-July, and the fruiting period is September. The height of the tree is less than 1 m, it is intertwined, furry, with many branches, dark bark and ancient shape. Torch tree has lush leaves and fluffy surface, which can absorb a lot of floating dust and harmful substances in the atmosphere. Cattle and sheep do not eat its leaves and are not harmed by pests and diseases. Torch tree has strong germination ability, fast natural reproduction ability and high afforestation survival rate, and can still be reborn with tenacious vitality after man-made destruction and forest fire. Torch tree also has the characteristics of high water content and low oil content in its branches, so it is not suitable for burning. It is an ideal tree species for closing hillsides for afforestation and a natural tree species for forest protection and fire prevention. The tree species has strong adaptability, drought resistance, ridge tolerance and salt tolerance. Developed roots can play a role in soil and water conservation, water conservation and ecological improvement. It is a rare tree species for greening and is known as an angel to beautify the environment and a pioneer to prevent soil erosion. Back to the top, the main uses are industrial oil, garden trees, flowers, Chinese herbal medicines and so on. Back to the top, for the purpose of greening, the female inflorescence and fruit sequence of Torch Tree Paint are as bright red as the torch. It stands on the top of the tree in summer and autumn, and its leaves turn red in autumn. It is an ornamental tree species with high ornamental value. Developed root system, strong tillering ability, is also a good tree species for dike reinforcement and slope protection. Rhustyphina, also known as antler paint. Rhamnaceae, Rhus. Native to North America. Morphological characteristics: Rhubarb is a deciduous shrub or small tree, and its height can reach 10m. Branches are few, branchlets are thick and dense brown, leaves are alternate, and odd pinnate leaves are compound. 9-27 leaflets, oblong to lanceolate, 5- 15 cm long; The top is long, tapering, the base is round or wide wedge-shaped, and the edge is neat and serrated; The leaves are green on the surface and white on the back, all of which are dense hairs. Dioecious, terminal erect panicle, female inflorescence and spike bright red, like a torch. The flowering period is May to July, and the fruiting period is 9-165438+1October. Growth habit: Torch tree is precocious, can blossom and bear fruit in four years, and can last for about 30 years. It is a positive tree species with strong adaptability. It likes to grow on the edge of river valleys, dams and swamps, and can also resist drought and poverty, and can grow on barren land on gravel slopes. Like cold and warm, acid and alkali resistant. It grows very fast and can be a forest in one year. Torch tree has shallow roots, developed horizontal roots and strong tillering germination, which is a good tree species for slope protection, dike closure and sand fixation. The female inflorescence and ear are bright red, and the branches are full in summer and autumn, which is beautiful; The leaves in autumn turn red and are very bright. It is an ideal tree species for soil and water conservation and landscaping. Bark and leaves contain tannin, which is the raw material for making tannic acid; The fruit contains citric acid and vitamin C, and can be used as a beverage. Seeds contain oily wax, which can be used to make soap and candles; Yellow wood, dense and beautiful texture, can be used for carving and textile crafts; Root bark can be used medicinally. Back to the top, the development value of Torch Tree is to conserve water and soil and conserve water resources. The root system of Rhubarb is shallow, generally distributed in the soil layer of 10 ~ 50 cm, and the horizontal root is long. 1 year roots can reach about 2.0 meters, and the germination ability of roots and tillers is extremely strong. The roots are densely planted with adventitious buds, and the roots can be found to germinate in gaps, which grow fast and close early. Torch tree is 3 years old. The planting method is simple and the survival rate is high. It is a pioneer tree species in difficult sites, such as afforestation in barren hills, bank protection and slope protection, beach sealing and sand fixation, and it is also the first choice for greening in arid and semi-arid areas in the central and western regions. Ornamental value Torch Tree is named after its beautiful appearance and ears resembling a torch. Especially in late autumn, its leaves are golden red, the distant scenery is spectacular, and it is also moving without leaves and flowers, which has high ornamental value. Torch tree can be used as a landscape tree species for greening on both sides of urban roads, factories, residential areas, schools, reservoirs and tourist attractions, and it is one of the excellent tree species for beautifying the environment and greening barren hills. Other Values Rhubarb has high tannin content and is an excellent raw material for producing tannin extract. Moreover, this kind of tannin extract belongs to mixed tannin extract, and its application field is very wide. Its roots, leaves, flowers, bark, seeds and wood are widely used. In addition, rhubarb grows fast and is one of the excellent fuelwood trees. If you operate in a bush-like way, you can get higher fuelwood. To sum up, rhubarb is not only drought-resistant, saline-alkali-resistant, barren-resistant, but also easy to breed, which has high ornamental and practical value. It is a good tree species for afforestation in difficult sites such as arid and semi-arid desert in northwest China, and it is worth popularizing in a large area. Back to the top propagation method, the seeds of the torch tree are very small, the seed coat is very hard, and the outside is pierced by red needles. Knead with alkaline water before sowing to remove red fluff outside the seed coat and wax on the seed coat. Then soak it in hot water at 85℃ for 5 minutes, take it out and bury it with wet sand, put it in a room at 20℃ to accelerate germination, and sprinkle water according to the evaporation of water. You can sow in 20 days. The sowing amount per mu is 7 ~ 10 kg, and the row spacing is 35 cm. Sprinkle the seeds into a ditch 2 cm deep, and then cover them with fine soil to make small ridges, which will help to keep moisture. Water should be sprayed properly to keep the soil moist. After 20 days, they were basically together. The height of the seedlings in that year was 80 cm, and the ground diameter was 1 ~ 1.5cm. The torch tree with broken roots has many lateral roots that extend horizontally. When the seedlings leave the nursery every year, lateral roots with a thickness of more than 65438±0cm are selected and cut into 20 cm long root segments. According to the polarity of the roots, the top is up, the stem is down, and the spacing is 40×30 cm, which is directly inserted into the whole nursery. After insertion, cover the top of the root segment with 2-4 cm thin soil and spray water frequently to keep it moist. Generally, adventitious buds are germinated first, new branches grow after breaking ground, and then take root and survive. Seedling height 1 meter. Roots and tillers are often planted around the torch tree, which is more than two years old. There are many roots and tillers that often sprout. According to the choice of row spacing, pay attention to pruning roots and excessive side branches to cultivate strong seedlings with good tree shape. In that year, the seedling height can reach 1.5 to 2 meters. It can be transplanted in the middle of March of the second year after breeding. Plant row spacing is 50× 40cm, watering, loosening soil and weeding should be done well, topdressing should be done once in May and June, and water and fertilizer should be stopped before the end of July. Torch trees generally don't get sick. The DBH of sowing seedlings and root-cutting seedlings can reach 3 ~ 5cm in 3 years and 3 ~ 5cm in 2 years, which can be used for afforestation. Back to the diurnal variation characteristics of photosynthetic physiology and ecology of clonal ramet at the top and clonal ramet of Vitex negundo, the difference of ecological adaptation of lower edge and outer edge of single dominant community of rhubarb to different light intensity was revealed. The diurnal course of photosynthesis of clones of Rhubarb and Vitex negundo was comparatively measured in the lower layer and outer edge of single dominant community of Rhubarb. The results showed that: ① Due to the decrease of photosynthetic effective radiation, rhubarb clones competed with Vitex negundo in the single dominant community of rhubarb, and the net photosynthetic peak value of Vitex negundo was 9.183 μ mol m-2s-1. The net photosynthetic rate of Vitex negundo in the community was only1.396 μ mol m-2s-1,and the peak net photosynthetic rate of Vitex negundo was lower than that of rhubarb clones. 2. From 13:00 to 17:00, the Fv/ ratio of rhubarb clones in a single dominant community. The phenomenon of high self-shading caused by clonal propagation of rhubarb is an important reason for the difference of photosynthetic physiology and ecology between rhubarb clones and Vitex negundo clones. First of all, urban construction must aim at eco-city, plant allocation should focus on local species, and introduction of exotic species should be extremely cautious. If the dominant tree species in a city are exotic or fast-growing trees, they will lose their characteristics. Since 100 years ago, China's landscaping has formed the habit of importing a large number of exotic tree species from overseas to drown our own street trees, such as French phoenix tree, British phoenix tree, American Robinia pseudoacacia, Australian eucalyptus tree, etc., which makes China's urban ecology lose its inherent characteristics. If we still do this now, even foreign friends can't understand, because China has the largest ecosystem and the third largest biodiversity in the world. Can't you choose garden plants with local characteristics? There are more than 1400 kinds of plants in the suburbs of Beijing, many of which have much higher ecological, ornamental and cultural values than exotic species. However, at present, there are still only 30 to 40 kinds of greening plants in the landscape planning department, and only 5 to 10 kinds of street trees, among which a large number of plants are exotic species, such as Torch Tree (Torch Tree has recently been selected as the six commonly used greening trees in Beijing), which greatly discounts the high starting point of Beijing eco-city construction. Second, Beijing is a city with rich cultural connotations and an ancient capital of the Six Dynasties. It needs a biodiversity collocation that reflects local characteristics to conform to the antique. Some trees should be able to become ancient trees, and most of the local tree species that have been naturally selected for millions of years are long-lived. Torch tree is a small fast-growing exotic tree species, and it can't be an ancient tree. In addition, its style is also out of tune with the antique of Beijing. This is because there is a piece of red everywhere, which destroys the harmony of the natural landscape and is easy to fall into stereotypes. In addition, the red color of Torch Tree is different from that of Quercus, Cotinus coggygria and Acer truncatum. The former leaves after frost, and the red time is short, so it is false red. The latter is resistant to wind and frost, with real red leaves and long period. If Beijing wants to build an international, modern and cultural capital where culture and tradition coexist, and modernity and nature coexist, it should take the lead in using local species in the whole country in a clear-cut manner and use exotic species cautiously, because, after all, urban forest construction is not from the economic and practical point of view, but from the use value of ecological aesthetics, natural harmony and natural culture. Therefore, torch tree, as a fast-growing tree species, is definitely unpopular in Beijing. In addition, China people's national self-confidence should be reflected. To love the motherland, we must first love the mountains, rivers, plants and trees of the motherland. British people also like Ginkgo biloba in China, but they will never take Ginkgo biloba as their own street tree! Third, once the torch tree is multiplied in large numbers and difficult to remove, it will form an invasive species, and the future trouble will be endless. Rhustopyhinal。 It is a deciduous shrub or small tree, native to North America, belonging to Rhustopyhinal. It was introduced to China by Institute of Botany, Chinese Academy of Sciences in 1959, and has been extended to China provinces since 1974. Originally, it was mainly cultivated in the provinces north of the Yellow River Basin, but now it is also widely cultivated in the Yangtze River Basin. On both sides of Beijing-Badaling Expressway, torch trees are used for highway greening. This species is very invasive, and can reproduce at an altitude of 500-3000m, with precipitation above 300mm, temperature between 25-45 degrees and annual average temperature above 8 degrees. The natural growth altitude of the place of origin is between 1300m-2200m, the annual precipitation is 800- 1200mm, and it adapts to the highest temperature of 42 degrees and the lowest temperature of -35 degrees, so it has a very broad ecological niche. Once you leave the country of origin, because of the loss of ecological balance, it will multiply in large numbers, endangering the natural ecosystem of the introduction place. Now we find that the place where the torch tree grows in patches basically excludes other species, which is very dangerous in the long run. Fourth, the secretion of the torch tree itself will cause adverse reactions of allergic people. Because rhubarb is a Rhus species, it has many secretions, including volatile oil, resin and water-soluble sugar conjugates, which can cause allergic reactions, such as skin swelling; In addition, it has a large inflorescence and produces a lot of pollen, so it is an exotic species. If planted in a large area, it is easy to cause allergic reactions of unsuitable people and form new allergens. To this end, we appeal that in the future construction of Beijing eco-city, we should use or stop using a large number of exotic species such as torch trees in urban greening to control the invasion of exotic species; A large number of local plants will be developed, so that Beijing's green Olympic construction will take a new step and become a torch. The fruit will not fall for a long time after ripening in September, and the leaves turn red after autumn, which is very spectacular.