Abnormal treatment method for Culture of Taxus chinensis var. mairei soil partial alkali leaves dry edge new leaves turn yellow

Taxus is relatively easy to raise, but in the process of breeding, it is impossible for all people to be plain sailing, how to deal with anomalies in the process of breeding yew? Like the leaves are yellow, but also dry edge, how can this do?

1. Soil partial alkali treatment.

Taxus is suitable for weakly acidic soil, such as long-term watering with alkaline water, it will cause leaves to change from green to yellow, or even leaves to fall off, due to the addition of acidic nutrients or spraying leaves or watering basin soil with 2/1000 ferrous sulfate solution, once every ten days, three times in a row.

Matters needing attention in fertilization

Do not apply fertilizer for three months after buying it back. As long as every seven to ten days, pour about 1000 times of potassium dihydrogen phosphate solution or foliar spray in the evening. Control the amount of water and don't water too much.

2. Dry edge treatment of leaves.

When the leaf color becomes light, the plant is thin, the leaf is yellowish white, the leaf tip appears "dry burning edge", and when the leaf senescence occurs prematurely, urea and potassium sulfate are applied to remove the precipitate and then irrigate the basin soil, once every other month or so. It is best to use rotten light bean cake fertilizer water (about 10%-15%), fertilizer to avoid the trunk, apply along the basin wall as far as possible, and apply once a month.

Pour clean water again the next day after fertilization, in case the fertilizer is too thick and dilute, the above two fertilizers can be used alternately, or you can dig two small pits in each basin and put five or six grains of urea and seven or eight grains of high-quality compound fertilizer in it. Then cover the soil and water it to dissolve the fertilizer. Taxus bonsai is not allowed to apply raw fertilizer and thick fertilizer. Topdressing should be based on nitrogen and phosphorus fertilizer, not too thick.

3. Pay attention to the placement

The yew bonsai is not easy to put in the air outlet of the air conditioner, the branches and leaves will dehydrate quickly, and the leaves will curl and dry up.

If you turn on the air conditioner in the air conditioner room every day, you should spray the foliar surface every day to maintain the foliar humidity and put a basin of water indoors.

In the room with heating in winter in the north, the heat sink should be dispersed far away, and a basin of water should be put on the radiator to increase the indoor air humidity.

4. Maintenance in summer and winter

Summer and autumn temperature more than 30 degrees Celsius should strengthen shading and cooling work, can be moved to the north ventilated room. Spray water to cool down when necessary to create a cool and humid environment to facilitate the growth of the yew.

To avoid the western sun directly shining on the yew, the watering amount of the bonsai should be controlled in winter to avoid the basin soil being too wet for a long time. Because the plant growth is not exuberant in winter, the volatile water of the leaves is less. If the basin soil is too wet for a long time, the surface of the basin soil will be hardened and impervious, which is easy to cause rotten roots. In indoor breeding, we must pay attention to indoor ventilation.

5. New leaves turn yellow

If the young leaves are dark yellow and dull, the phenomenon of withering at the top of the new shoot is generally caused by overwatering too much soil and impermeable so that part of the roots rot and absorb water. When the ability to absorb fertilizer is weakened, the amount of water should be controlled if the symptoms are mild, and the basin surface soil should be gently loosened with hard and blunt objects to make the basin soil breathable, move to a place that can accept dew every night, and move to a shady place at eight or nine o'clock in the morning, which is conducive to the healthy growth of the root system.

If the leaves are yellowed and curled in a short period of time, it means that the root rot is serious, because immediately turn the basin to check the root rot condition, (the normal fibrous root shows a full white shape), if more than half, generally save not alive.

6. The old leaves turn yellow (they fall off as soon as they are touched)

The old leaves turn yellow and the new leaves are normal, which is generally caused by the lack of water in the roots and the lack of water in the roots.

The leaves at the top are dry and curly and fall off a large piece, which is also caused by the lack of water at the root, which should be watered thoroughly at one time.

How to handle it:

Watering first compacts the cracks on the edge of the basin with objects to prevent the water from leaking quickly from the cracks. You can move outside at night to receive rain and dew, and two hours of sunshine in the morning and evening can restore the growth of the yew.

7. Maintenance tips:

Every year in March and April, the yew will sprout a large number of buds and consume a lot of nutrients. At this time, the buds growing toward the inside can be removed to prevent the leaves from yellowing or falling off because the branches are too dense and unventilated. For cross branches, inward branches grow and cut sparsely, which can improve ventilation. Transparent light, and can save the excessive consumption of water and nutrients, it is best not to spray liquid fertilizer on the leaf surface at the beginning of bud germination, or to pour thick fertilizer on the root.

This is the end of the method to deal with the abnormal phenomena of the yew in the process of culture, so that the yew can be cultivated happily.

Yew pot culture method [guide] Taxus is a shade-loving plant, should not be in the window sun, every day to spray water to maintain humidity, at any time like shade plant, but not without the sun, you can bask in the sun here, but to the right amount, morning and evening ventilation twice, 15 minutes each time is appropriate, ventilation time 9-10 in the morning is the best, hot weather spray water twice a day, the page dripping is appropriate. If you are watering and irrigating, you must water it thoroughly at one time, and do not water it at both ends of the day. Taxus is a shallow root plant, its main root is not obvious, lateral root is developed, it is recognized as an endangered natural rare anticancer plant in the world, is an ancient tree species left over from the Quaternary glacier, has a history of 2.5 million years on the earth. Because in the natural condition the yew growth rate is slow, the regeneration ability is poor 1, the yew sex likes the shade, does not want the sunlight directly, displays in the living room, the bedroom, the balcony corner can. In the evening, you can put it on the windowsill to make it breathable, and the choice of watering time can be judged from the following two aspects: (1) the leaves of the yew are tall and straight and bright, and if the page is tired, it will be watered. If the leaf is drooping, it shows that the lack of water is serious. (2) tapping the basin several times with your hands, you can tell from the sound that if the sound is empty, it means that the soil is dry and needs watering. (3) judging from the basin soil, insert your finger into the soil 2-3 cm, feel the soil dry, and need watering. Plants need different amounts of water in different periods, with more water in the growing period (March-November) and less in the dormant period (December-February). As for the period of watering can not be unified, spring and autumn generally 5-7 days watering, summer 3-5 days watering, winter 7-10 days watering 3, the surrounding environment. Taxus does not have great requirements for the environment, in addition to achieving the first point not to direct sunlight, but also pay attention to do not blow directly into the air conditioner, do not go near the heating in winter, do not casually throw cigarette butts, tea and other sundries into the basin. 4. If there are withered and yellow leaves or diseases and insect pests, methyl topiramate and potassium dihydrogen phosphate can be used to irrigate or spray. The general dosage is: 1-2 liters of water in a small bag. 5. Taxus should be ventilated to avoid direct sunlight. Do not blow directly to the air conditioner in summer, do not go near the heating in winter, because the northern climate is dry and less rain, when the soil surface is dry, it can be watered, pay attention to one-time watering, especially in summer. When the air is dry in the north, the leaf surface is easy to droop due to lack of water, and when the leaf surface is not full, you need to spray water from the bottom up with a small spray can (you can spray it every day in summer). Taxus is a shade-loving plant, which is suitable to be placed indoors, but it should not be placed at the air outlet of the air conditioner or next to the heating, otherwise it will increase the water evaporation of the leaves of the yew and make the branches and leaves of the yew dehydrated quickly, causing the leaves to curl and dry up. 7. The yew bonsai should not be irrigated with tea water. In particular, the water quality in Beijing is hard and the alkali content is high, so the water must be used for watering and spraying after one day. "Disease and insect pest control" during the rainy season, individual young trees of Taxus chinensis var. mairei will have root rot, stem rot and rotten roots, which can be treated with 70% dimethazone 500 × 800 times; in high temperature and dry seasons, leaf blight and red blight will occur in individual young trees, which can be controlled by spraying 1% Bordeaux solution. Young trees of Taxus chinensis var. mairei have few insect pests. "bonsai trimming" Taxus chinensis var. mairei is exuberant, resistant to pruning and can be shaped arbitrarily. Through artificial pruning, it can be trimmed into umbrella-shaped, tower-shaped, round-shaped and other shapes of Taxus mairei bonsai. At the same time, in order to keep the crown of Taxus chinensis var. mairei beautiful, the terminal bud and some lateral buds can be removed moderately. First, try not to spray fertilizer on the leaves of the newly purchased yew bonsai just sprouting, because at this time the yew bonsai has not really survived or the leaves are too tender, if fertilization will make the leaves or buds shrink and curl. Thus affect the normal germination of new roots, foliar spraying water is not too much, to the foliar surface can see the spray of water but not dripping down for the degree. Spray two hours before dark in the afternoon, do not leave water droplets in the evening (especially when there is a large amount of water), otherwise it will affect the normal growth of tender leaves or the leaves will turn yellow, affecting the healthy growth of plants. The reverse side of the leaf can be sprayed more than the front, because there is a waxy protective film on the front of the leaf, which will hinder the absorption of nutrients and water, while the back of the leaf has no waxy layer, has more stomata and has a strong ability to absorb water and fertilizer. So the back absorbs faster and more than the leaf surface. Depending on the situation and the temperature, once a day or two or three times a day. Note that the room should be ventilated regularly. 2. For the newly purchased yew bonsai with a height of about 40 cm, part of the root system will be damaged when transplanting from the planting base to the flowerpot, so that the nutrient supply between the root and the branches will be out of balance, especially for those bonsai with luxuriant branches and leaves. the evaporation of the leaf surface is greater than the absorption of the root system, and the top leaves curl and dry when the potted soil remains moist, so it is best to prune the branches and leaves properly. In order to reduce the moisture content of branches and leaves. Excessive consumption of nutrients should restore root growth as soon as possible, and at the same time, watering should be controlled to keep the basin soil slightly dry, so as to facilitate root growth as soon as possible and speed up the restoration of normal nutrient supply. At the same time, Taxus has strong sprouting ability, especially the new branch growth ability is strong and resistant to pruning, and it will sprout new branches and leaves soon after survival. When necessary, plant rooting or rooting enhancers can be used to irrigate the basin soil every seven days or so, and continuously irrigate three or four times (using good quality products and not too much water) so that the roots can grow quickly and healthily. Restore the supply balance between roots and leaves as soon as possible, and make the yew grow well. Third, as the yew bonsai is planted in the flowerpot with limited nutrients, it can only provide about half a year for growth, or now the plant shape is larger and the nutrient consumption is very large, so it is suggested that consumers had better replace the original pot as soon as possible after purchase. Because our company for bonsai for more than a month of re-bonsai, and stored in the distribution company for a period of time, plus yew like rich and loose soil. It is best to change the basin as soon as possible, when changing the pot to calculate the inner diameter of the flowerpot, the inner diameter of the new pot should be at least five centimeters larger. Before the new buds germinate in February and March every year, pour out the tree and the pot soil together when the basin soil is not dry or wet. Try not to break the original soil ball, if you find that there are too many roots after survival, you can properly cut off the bad roots, put the tree in a new basin, fill it with nutritious soil and press it gently, and only close the soil and roots in the basin can you improve the survival rate. otherwise, the plant is not easy to survive or does not grow vigorously. However, the soil should not be pressed too firmly, if the air cannot be breathed from the roots, the roots will rot and the plants will die. Water thoroughly immediately after planting. And leave the basin in the shade for a few days. After watering, the basin soil can no longer be turned over and pressed, otherwise the basin soil is easy to consolidate, or the soil is too solid and breathable and easy to cause rotten roots. Fourth, the fertilization method of yew bonsai: plant growth needs nitrogen, phosphorus and potassium fertilizer, nitrogen fertilizer can promote the growth of flowers and plants, phosphorus fertilizer can promote the formation of flowers and fruits, and potassium fertilizer can promote stem and root growth. Because the bonsai is in a limited bowl space. Limited cultivation soil, organic matter is broken down into inorganic salts by bacteria and absorbed by roots. With the consumption of Taxus growth, the nutrients in the basin soil are gradually lacking, resulting in insufficient demand for growth. Although the prepared nutritious soil is used in the bonsai, do not apply fertilizer within three months after buying it back. As long as every seven to ten days, pour about 1000 times of potassium dihydrogen phosphate solution or foliar spray in the evening. Control the amount of water and don't water too much. Only when the leaf color becomes light, the plant is thin, the leaf is yellowish white, the leaf edge appears "dry burning edge" at the leaf tip, and the leaf senescence occurs prematurely, apply 1000 times liquid urea and potassium 800x instant high-quality compound fertilizer solution to remove the sediment and then irrigate the basin soil. once every other month or so, it is best to use fully mature light bean cake fertilizer water (about 10% 15%) to avoid the tree trunk and apply along the basin wall as far as possible. Apply once a month. Pour clean water again the next day after fertilization, in case the fertilizer is too thick and dilute, the above two fertilizers can be used alternately, or you can dig two small pits in each basin and put five or six grains of urea and seven or eight grains of high-quality compound fertilizer in it. Then cover the soil and water it to dissolve the fertilizer. Taxus bonsai is not allowed to apply raw fertilizer and thick fertilizer. Topdressing should be based on nitrogen and phosphorus fertilizer, not too thick. Fifth, the watering method of bonsai: the principle is "no dry, no watering, then watering" water is an important part of flowers and trees, all life activities of flowers and trees should be carried out with the participation of water, whether it is photosynthesis or transpiration, can not be separated from water, water can maintain the swelling and pressure of cells, make branches and leaves straight. But beyond the limit, the plant growth is thin and weak, such as long-term basin soil too much water, it will cause leaves yellowing, deciduous leaves, rotten roots, and even death. (1) look at the slightly lighter color on the surface of the basin soil, the leaves slightly curl, press the basin soil with your fingers and feel a little soft, and when the sound from tapping the middle and upper part of the basin body with finger joints is relatively dull, the basin soil does not need to be watered, as long as the leaf surface is sprayed to replenish the moisture of the leaves. When the surface of the soil is white, press with your fingers and feel that the soil is hard, and there is a circle of cracks between the basin and the soil, when tapping the middle and upper part of the basin with finger joints gives a clear sound of "bang bang", when the young leaves of the new shoots are withered, the basin soil should be watered. The cracks between the soil and the basin should be compacted with hard objects before watering, and then poured with a large spoon. When pouring water, the spoon should be close to the edge of the basin, and the spoon should be poured in all at once, so that the basin soil can absorb enough water. If you pour a small amount of water into the basin for a while, you can see that the water flows out quickly from the bottom of the basin, indicating that the soil and the basin are not completely compacted. The gap between the basin wall and the soil is pressed and then poured by the application object. When the basin soil structure is normal, it is better for water to seep out slowly from the bottom of the basin for about 40 seconds to one minute after watering. The water temperature must be close to or consistent with the air temperature at that time. When using tap water, you should first put the water in the sun for about three hours before watering, because the light helps to decompose the oxides in the tap water and increase the water temperature. You can also put the water in the big basin for half a day or one night and then water it. If there are many bonsai, you'd better put the water in the big tank to make the water temperature as close as possible to the air temperature and soil temperature. Especially in the hot season, in addition to watering the basin soil, it is also necessary to spray water spray on the leaves to keep them moist for growth. When the basin soil can be kept a little dry and not too wet, each basin must be checked in the light of the actual situation, and be careful not to water too much. (2) the evergreen leaves of Taxus chinensis var. mairei are suitable to be placed indoors. However, the yew bonsai is not easy to be placed in the air outlet of the air conditioner, otherwise it will increase the water evaporation of the yew leaves, easily cause the branches and leaves of the yew to dehydrate quickly, and cause the leaves to curl and dry up. If you turn on the air conditioner in the air conditioner room every day, you should spray the foliar surface every day to maintain the foliar humidity and put a basin of water indoors. In the room with heating in winter in the north, the heat sink should be dispersed far away, and a basin of water should be put on the radiator to increase the indoor air humidity. Summer and autumn temperature more than 30 degrees Celsius should strengthen shading and cooling work, can be moved to the north ventilated room. Spray water to cool down when necessary to create a cool, moist environment to facilitate the growth of the yew. And avoid the western sun shining directly on the room on the yew bonsai. The watering amount of bonsai should be controlled in winter to avoid long-term over-wetness of potted soil, because the plant growth is not exuberant in winter, the volatile water of leaves is less, if the potted soil is too wet for a long time, the surface of potted soil will be hardened and impervious, and it is easy to cause rotten roots. The yew must pay attention to the indoor ventilation when raising the yew indoors. (3) the soil quality of yew planting should be loose, rich in humus, fertile, slightly acidic soil (between PH=5.5~7), yew bonsai can not pour tea water, if you often pour the rest of the tea water, because the tea water contains theophylline and other alkaloids. If the pH of the soil is changed for a while, it will also destroy the organic matter nutrients in the soil. It can inhibit the growth of Taxus and cause excessive soil moisture, hinder the ventilation of basin soil, and cause root rot and stem rot. When there are conditions for a week or so, moving the yew bonsai to the balcony in the evening to receive dew and exposing it to the sun for about one or two hours in the morning (before 10:00 in the morning) is beneficial to the growth of the yew and improve its disease resistance. In summer and autumn, it is necessary to prevent the western sun from shining directly on the yew through the window, so as to prevent the high temperature burning leaves from affecting the ornamental value. Six; (1) attention points: because the tree is small, yew No. 2 should pay attention to the adjustment of light, so it needs light, but it can not be placed in the strong light for too long. It can be basked in about two hours before ten o'clock in the morning or after five o'clock every day in summer and autumn. Usually accept more scattered sunlight. Otherwise, the leaf tip will be scorched yellow due to strong light burns, and the indoor ventilation will be maintained, so that the indoor air will not be withered, sagging and other bad growth phenomena. (2) if the young leaves of the new bonsai appear dark yellow and dull, the withering phenomenon of the top of the new shoot is generally caused by overwatering too much soil and impermeable so that part of the roots rot and absorb water. When the ability to absorb fertilizer is weakened, the amount of water should be controlled if the symptoms are mild, and the basin surface soil should be gently loosened with hard and blunt objects to make the basin soil breathable, move to a place that can accept dew every night, and move to a shady place at eight or nine o'clock in the morning, which is conducive to the healthy growth of the root system. If the leaves are yellowed and curled in a short period of time, it means that the root rot is serious, because immediately turn the basin to check the root rot condition, (the normal fibrous root shows a full white shape), if more than half, generally save not alive. (3) Yellow leaves occur in the old leaves from the bottom up, but the new leaves generally grow normally, which is generally caused by the lack of water in the roots and the lack of water in the roots. Sometimes the top leaves dry and curl, touch the dry leaves fall, but the old leaves grow normally, generally caused by the lack of water in the roots, should be watered thoroughly at one time. When watering, the cracks on the edge of the basin must be compacted with objects to prevent the water from quickly leaking from the cracks. To create the illusion of being thoroughly watered, the roots will die due to lack of water over a long time. Move outdoors at night to accept more rain and dew, and receive two hours of sunshine in the morning and evening to restore the growth of the yew. (4) Taxus is suitable for weakly acidic soil. If it is irrigated with alkaline water for a long time, it will cause leaves to change from green to yellow, or even leaves to fall off, due to the addition of acidic nutrients or spraying leaves or watering basin soil with 2/1000 ferrous sulfate solution, once every ten days, three times in a row. It can make the leaves turn green due to alkali yellow. (5) in March and April every year, the yew will sprout a large number of buds and consume a lot of nutrients. At this time, the buds growing toward the inside can be removed to prevent the leaves from yellowing or falling off because the branches are too dense and unventilated. For cross branches, inward branches grow and cut sparsely, which can improve ventilation. Transparent light, and can save the excessive consumption of water and nutrients, it is best not to spray liquid fertilizer on the leaf surface at the beginning of bud germination, or to pour thick fertilizer on the root. (6) if the normal amount of fertilizer is applied with urea only, the concentration of nitrogen fertilizer is generally 1/1000, and if potassium dihydrogen phosphate is used alone, the concentration of phosphate fertilizer is 1/1000 to 2/1000, with an interval of seven to ten days. The soil of potted yew is the best in loam, and peat soil and perlite can also be mixed with loam. Water conservation, fertilizer conservation and ventilation are beneficial to the growth of Taxus chinensis. Although clay preserves water and fertilizer, it is impervious to air, which is not conducive to the growth and development of Taxus chinensis root system. Although the sand is breathable, it is poor in fertilizer and water retention, which is not conducive to the growth of Taxus chinensis. The best light of the yew is from 7 am to 11:00 every day, about 4 hours a day, shorter in summer and longer in autumn and spring. But the lack of light also affects the photosynthesis and growth of Taxus chinensis.

Culture methods and matters needing attention of Taxus mairei

Taxuschinensis (Pilger) Rehd.

Also known as flat cypress, red bean tree, yew

Binomial Taxuschinensis

The plant kingdom.

Door, pine and cypress door.

Subphylum gymnosperms

Class pine and cypress class

Taxus chinensis

Taxodiaceae

Genus Taxus

Plant Taxus

The distribution areas are mainly produced in Shaanxi, Sichuan, Yunnan, Guizhou, Hubei, Gansu, Hunan and Guangxi.

Environmental distribution in alpine limestone mountain areas

Shallow root plant with ecological habit

Life form evergreen tree

Sunshine and shade

Water drought tolerance

The optimum temperature is 20: 25 ℃

Sandy loam

As high as 1000-1200 meters above sea level

Edible value leaf pericarp can be processed into tea

Medicinal value of diuresis and detumescence

Industrial value purified paclitaxel, wood carving

Special purpose greening and ornamental

Toxic. Toxic.

Symbolize longevity

The height of the plant is about 30m.

Taxus, also known as Yew, is a plant of the genus Taxus. Taxus is a shallow root plant. Its main root is not obvious and its lateral root is well developed. it is recognized as a natural rare anticancer plant on the verge of extinction in the world. It is an ancient relict tree species left over from Quaternary glaciers and has a history of 2.5 million years on the earth. Due to the slow growth rate and poor regeneration ability of Taxus under natural conditions, there has been no large-scale yew raw material forest base in the world for a long time. In 1994, Taxus was designated as a first-class rare and endangered plant in China, and at the same time, it was called a "national treasure" by 42 countries with yew in the world, and logging was also banned by the United Nations. It is a veritable "plant giant panda". Taxus is an evergreen tree with alternate branchlets that turn yellowish green or reddish brown in autumn; winter bud scales with round or obtuse ridges on the back; sickle-shaped leaves, diallel, 1.5 Mel 3 cm long, wider than other Taxus, with pointed and small ends, with two yellow lines at the bottom; flowers axillary, dioecious, female flowers with only one ovule and several receptacle scales. Flat ovate seeds, each with an inconspicuous ridge on each side, surrounded by a red cup-shaped aril.

1. Morphological characteristics.

The yew is up to 30 meters tall and has a breast diameter of 65-100 cm; the bark is grayish brown, reddish brown or dark brown, splitting into strips and falling off; big branches unfold, annual branches are green or yellowish green, and autumn turns green yellow or light reddish brown; biennial branches are yellowish brown, light reddish brown or grayish brown; winter buds are yellowish brown, light brown or reddish brown, glossy; winter bud scales are round or with obtuse ridges on the back Leaves striate, dioecious, seeds oblate. Seeds are used to extract oil and can also be used as medicine. Belongs to the shallow root plant, its main root is not obvious, the lateral root is developed.

Leaves spirally alternate, base twisted into distichous, strip slightly curved, long 1~2.5cm, wide 2~2.5mm, leaf margin slightly reflexed, leaf tip acuminate, leaf back with 2 broad yellow-green or gray-green stomatal bands, midvein densely covered with fine bumps, leaf margin green belt is very narrow, dioecious, male cones solitary in leaf axils, female ovules solitary on top of lateral short axis above rachis, base with disc-shaped aril. Seeds oblate-ovoid, 2-angled, seed ovoid, aril cup-shaped, red.

2. Growth habits

Taxus chinensis var. mairei is suitable to be planted in the north and south of China, and it has the characteristics of shade, drought and cold resistance, and the soil PH value is required to be 5.5-7.0.

The environment is shady, can also grow under the dense forest, perennial, can not become a forest. It is more common in the coniferous and broad-leaved mixed forest dominated by Korean pine. Born on stony or barren soil on the top of the mountain, most of them are shrubby. The average annual temperature in the place of origin is 2 ℃ to 7 degrees, and the average annual precipitation is 750-1000 mm. Mostly scattered under the moist, fertile coniferous and broad-leaved mixed forest on shady or semi-shady slopes. Sex likes cool and humid climate, can withstand low temperature below minus 30 ℃, strong cold resistance, the optimum temperature is 20: 25 ℃, it belongs to negative tree species. Like moist but afraid of waterlogging, suitable for planting on loose, moist and well drained sandy loam.

3. Distribution range

It is widely distributed in Lechang, Guangdong, Shaanxi, Hubei, western Anhui, Fanjing Mountain and Fuding Mountain in Tongren City, Sichuan Province, most areas in southwest Chongqing, Youyang Dabanying primeval forest, southern Gansu and so on.

With the exception of Australia's Austrotaxus Spicata, which is found in the southern hemisphere, the rest of the yew is produced in the northern hemisphere. There are 4 species and 1 variety of Taxus chinensis, which are distributed in most parts of China. Taxus mairei is mainly distributed in Changbai Mountain and Heilongjiang in Jilin Province, and a small amount in the mountainous area of eastern Liaoning. Taxus yunnanensis is mainly distributed in 16 counties in western Yunnan and prefecture with a total area of about 90,000 square kilometers, which is characterized by wide distribution, scattered growth, no pure forest and mostly scattered trees in the forest. Taxus mairei is mainly distributed in pure forests in eastern, southwestern and eastern Yunnan, mostly scattered trees in the forest.

4. Related species

Taxus chinensis var. mairei Taxuschinensis (Pilger) Rehd. Var.chinensis

Trees, up to 30 m tall, DBH up to 60-100 cm; bark grayish brown, reddish brown or dark brown, split into strips; large branches spreading, annual branches green or yellowish green, turning green yellow or light reddish brown in autumn, biennial branches yellowish brown, reddish brown or grayish brown Winter buds yellowish brown, light brown or reddish brown, glossy, bud scales triangular-ovate, dorsally ridged or longitudinally ridged, deciduous or few persistent at base of branchlets. The leaves are arranged in two rows, striped, slightly curved or straight, 1-3 (mostly 1.5-2.2) cm long and 2-4 (mostly 3) mm wide, slightly narrowed at the upper, apex often slightly acute, sparse acute or acuminate, dark green above, glossy, yellowish green below, with two stomatal bands, and a dense, uniform and tiny round horny papillary process starting point on the midvein belt, often of the same color as the stomatal belt, and light in sparse color. Male cones are yellowish, with 8-14 stamens and 4-8 anthers (mostly 5-6).

The seed is born in the cup-shaped red fleshy aril and occasionally on the submembranous disk-shaped receptacle (that is, the pearl that has not developed into a fleshy aril). It is often oval, narrowing at the upper part, Obovate, 5-7 mm long, 3.5-5 mm in diameter, slightly flat or round, with two obtuse ridges in the upper part, three obtuse ridges in the sparse upper triangle, and a short obtuse tip protruding at the apex, and the navel is nearly round or broadly elliptic. Thin triangle-shaped circle.

Found in southern Gansu, southern Shaanxi, Sichuan, northeastern and southeastern Yunnan, western and southeastern Guizhou, western Hubei, northeastern Hunan, northern Guangxi and southern Anhui (Huangshan), often in the upper part of the mountains above 1000-1200 meters above sea level. It is cultivated in Lushan, Jiangxi.

Taxus chinensis var. mairei Taxuschinensis (Pilger) Rehd. Var.mairei (Lemee et Levl.) Cheng et L. K. Fu

The main difference between this variety and Taxus mairei is that the leaves are usually wide and long, mostly falcate, usually 2-3.5 (- 4.5) cm long and 3-4 (- 5) mm wide, the upper part is often narrowed, the apex acuminate, and there is no starting point of horny papillary process on the lower midvein band, or there are local or sporadic cuticular papillary process starting points on both sides of the midvein belt adjacent to the stomatal zone. The midrib band is clearly visible, and its color is different from that of the stomatal zone, showing yellowish green or green, and the green edge band is also wide and obvious. The seeds are usually large, slightly flat, mostly Obovate, the upper part is wide, the sparse columnar moment is round, 7-8 mm long, 5 mm in diameter, and the navel is often oval.

Found in southern Anhui, Zhejiang, Taiwan, Fujian, Jiangxi, northern Guangdong, northern and northeastern Guangxi, Hunan, western Hubei, western Henan, southern Shaanxi, southern Gansu, Sichuan, Guizhou and northeastern Yunnan. The vertical distribution is generally lower than that of Taxus mairei, and it is often born below 1000-1200 meters above sea level in most provinces.

5. Current situation of protection

The current situation is that because the bark of the yew has an anticancer substance, paclitaxel, many people go into the forest to peel the bark, resulting in a sharp decline in the number of yew. The reason for the extinction of the yew is that in the early 1990s, an American company discovered that paclitaxel in the bark of the yew has an anti-cancer effect. When the news spread to China and Yunnan, people suddenly realized that the treasure was around, people were frantically peeling yew, and no one paid attention to the detailed regulations on the Protection of Precious Tree species in Yunnan Province. the lives of more and more yew came to an abrupt end overnight.

The State Forestry Administration has made clear instructions on the "yew project": "Taxus is a first-class protected tree species in China, with good ecological benefits and extremely high economic value. The state supports vigorously building a yew forest in an appropriate range, and all sectors of society to participate in the afforestation and greening cause in the form of contracting, leasing, auction, stock cooperation and other forms should be promoted and encouraged."

Liangyeshan National Nature Reserve is the first national yew nature reserve in China, and it is also the only national nature reserve with Taxus mairei as the protection object.

Muling Taxus mairei Nature Reserve was approved as a national nature reserve in 2009, and more than 160000 trees of Taxus cuspidata known as "giant pandas in the plant world" will be further effectively protected.

The nature reserve, originally a provincial reserve, is the largest and best-preserved concentrated distribution area of wild Taxus mairei in the northeast forest region. Taxus mairei, also known as yew, is an endangered species in the world and a rare and protected tree species in the country.

Muling Northeast Taxus Nature Reserve is located at the northern end of Changbai Mountains and the southern foot of Xiaoxing'an Mountains, within the jurisdiction of Muling Forestry Bureau, with a total area of 35000 hectares.

The thousand-year-old yew in the three groups of Huangdimiao Village, Duba Township, Beichuan, is known by the local people as the "sacred tree" of the yew. According to the measurement, the circumference of the tree is 5.3 meters, the height of the tree is 24.7 meters, and it takes four adults to embrace the trunk. Beichuan has built a fence around the tree and asked someone to protect it. Luo Jingcheng, a 68-year-old villager, said that because locals regard the tree as a "sacred tree", even if too many red beans are produced every year, no villagers will climb the tree to pick them, but just pick them under the tree.

6. Cultivation techniques

Reproduction methods seed propagation

Taxus mairei is mostly propagated by seeds. After the seeds are ripe in November, the fleshy seed coat is washed and dried, then buried in a shady dry place with wet sand, covered with plastic film and grass curtains. The seeds should be turned twice a month in summer and autumn, and the seeds can be sowed and raised at the beginning of March of the following year. The seedbed should choose a leeward and well-drained slightly acidic sandy soil, with a bed width of 1 meter, a ditch width of 40 centimeters, a high ridge from east to west, and a steel plate 25 centimeters high and 4 centimeters thick on both sides of the ridge, with a depth of 10 centimeters. The bed soil requires deep ploughing and fine farming, and carbofuran is applied to control underground insect pests. Use vermiculite, river sand, peat, garden soil, and add carbendazim or methyl thiophanate and other fungicides, mixed into the matrix into the steel plate, 3-5 cm higher than the middle of the side plate. Cover with plastic film and seal and fumigate for 3 to 5 days before sowing. The seeds are distributed evenly on the bed, with about 200 seeds per square metre. After sowing, the seeds are slightly flattened with a wooden board, covered with mixed matrix soil 1 to 2 cm thick, and covered with grass curtains or plastic film for heat preservation and moisturization. Spray water properly in case of dry weather, generally sprouting and sprouting after 40 days. At this time, we should remove the plastic film or grass curtain, and set up a 2-meter-high shade shed above the seedling bed to cover the shade net to prevent direct sunlight. Keep the seedbed moist, build a low arch shed and cover the plastic film on rainy days to prevent too much moisture in the seedbed. Do a good job of drainage and ventilation of seedling bed, timely prevention and control of diseases and insect pests. Apply rotten fresh cake fertilizer and water every 10 days in the seedling stage, and avoid chemical fertilizer and concentrated fertilizer. After a year of careful maintenance and management, the height of the seedlings can reach 15,25cm and have 2 to 3 bifurcated branches. Transplantation can be carried out in early April. The planting land should choose leeward, dry, slightly acidic sandy soil rich in humus, with a depth of 20 cm and 5 kg of mature organic fertilizer per square meter. Rise high ridge, dig deep ditch, ridge width 100 cm, ditch width 30 cm. 5 rows per row, 20 cm between rows and 15 cm between plants. Transplant should be in cloudy days, should be moved with the species, need to transplant with soil balls. Immediately after transplanting, pour water once, and build a 2-meter-high shade shed on it, cover the shade net on sunny days, and remove it on rainy days and at night. Strengthen fertilizer and water management during the growing period, generally applying rotten cake fertilizer and water every 10 days. Do a good job in the control and management of diseases and insect pests. Strengthen shading and cooling in summer and spray water when necessary to create a cool and humid environment conducive to seedling growth. Taxus is not only an excellent material for making high-grade furniture, but also a medicinal material with great medical value, but also an excellent tree species for landscaping. With the maturity and development of its artificial reproduction and cultivation technology, the application range of Taxus will be more extensive.

When breeding seedlings with Taxus seeds, attention should be paid to the storage mode of seeds, mixed storage of sand seeds or temperature control treatment, which has a good effect on sprouting and breaking dormancy habits after overwintering. Before sowing, the seed coat should be rubbed, the seeds should be soaked in warm water and treated with chemicals and hormones. Shading after emergence is the key to raising seedlings. It can prevent the seedlings from burning at high temperature and keep it moist and translucent at 40%. The emergence rate of Taxus chinensis var. mairei and Taxus chinensis var. mairei can reach 7080%, and the seedling emergence temperature is required to be higher than 15 degrees.

The dynamic growth of seedlings was as follows: the plant height and stem diameter of seedlings grew slowly in the first two years of emergence, the plant height generally grew about 10cm a year, and the growth accelerated one year after transplanting. The annual increase of 3 ~ 5 years can reach 20~30cm.

Cuttage propagation

For the cuttage propagation of Taxus mairei, it is better to use twigs in spring and hard branches in autumn. Generally, low-shed shading should be done when cutting. Generally, the survival rate of cutting can reach more than 70%. While conventional cuttings are only about 3% to 20%. The shading rate is not less than 60%. The base of cuttings should be treated carefully. The humidity should be kept at about 750.85% intermittently at the beginning. Avoid water loss caused by strong winds.

The factors affecting the survival rate of cutting are generally: tree age, temperature, concentration of chemical treatment, substrate, season, humidity, variety, and other human factors and so on.

In the process of rooting in the first year, the aboveground part of cuttings grew slowly, but rooting rapidly and lateral roots developed. After transplanting in the second year, further shading treatment and seedbed management are needed. To ensure the corresponding environmental conditions, the growth is accelerated. The growth rate is the fastest in summer and slow in winter and spring. At this time, we should pay attention to the change of temperature, long-term drying can cause growth inhibition or sudden death. However, after the seedlings are strengthened in the seedling bed, the survival rate of Taxus mairei is very high. Rarely die and grow rapidly.

Seedling management

Temperature regulation

After cuttings, the ground temperature of the bed should be maintained at 18 ℃ ~ 25 ℃, the temperature in the shed should be 22 ℃ ~ 28 ℃, and the soil moisture should be 60% ~ 70%.

Seedling stage management

Observe the temperature and humidity in the plastic shed every day. When there are water droplets in the plastic film of the bow shed, there is no shortage of water. When there is no water droplets, it is lack of water. When there is no water, open the plastic film to receive rain or water properly. When the temperature in the shed reaches 30 ℃, the plastic at both ends of the arch shed should be opened in time for ventilation. Seal the plastic film after sunset to keep the temperature in the shed. Remove the upper shade net before snow and move it under the plastic in the bow shed to continue to shade to prevent direct sunlight on the seedlings. About 45 days after cutting, the cuttings began to take root, and basically took root in about 65 days, and 3-5 cm shoots could grow in the same year. After 2 years, transplanting can be carried out, when the root system is more developed and easy to survive. When it grows to 6-8 years old, the sapling is 80-90 cm high.

Weeding and disease prevention

Weeding should be carried out when the grass is just growing. If the grass is big and strong, it will be pulled out together with the seedlings accidentally, or the wind leakage will lead to the death of the seedlings, so it is necessary to pull the grass early and weed frequently to avoid the loss of water and fertilizer. Taxus seedlings are prone to root rot and stem rot in the rainy season. 70% Diexong 400 times liquid can be sprayed and irrigated: seedlings are easy to get leaf blight in the dry and high temperature season. Spray 1% Bordeaux solution to control.

Tissue culture

Tissue culture takes advantage of the totipotency and clonability of plant cells. The tender stem, needles, bark, cambium, aril and embryo of Taxus chinensis were used as explants for culture.

1. Taxus chinensis var. mairei was selected as explant, and a large number of tissue culture seedlings could be obtained in the laboratory after callus formation, rooting, seedling bud formation and so on. After substrate transplanting, seedling training, inspection and epidemic prevention, it becomes a vaccine for production.

2. The ratio of late to early callus formation of Taxus chinensis var. mairei was different among different species and different plants of the same species. At the same time, it is related to the type of explant, sampling site, collection season, light condition, medium type and so on.

Pot conservation 1, for the newly purchased yew bonsai just sprouting new buds, try not to spray fertilizer liquid, because at this time the yew bonsai has not really survived or the leaves are too tender, if fertilization will make the leaves or buds shrink and curl. Thus affect the normal germination of new roots, foliar spraying water is not too much, to the foliar surface can see the spray of water but not dripping down for the degree. Spray two hours before dark in the afternoon, do not leave water droplets in the evening (especially when there is a large amount of water), otherwise it will affect the normal growth of tender leaves or the leaves will turn yellow, affecting the healthy growth of plants. The reverse side of the leaf can be sprayed more than the front, because there is a waxy protective film on the front of the leaf, which will hinder the absorption of nutrients and water, while the back of the leaf has no waxy layer, has more stomata and has a strong ability to absorb water and fertilizer. So the back absorbs faster and more than the leaf surface. Depending on the situation and the temperature, once a day or two or three times a day. Note that the room should be ventilated regularly.

Second, for the newly purchased yew bonsai, due to the damage to part of the root system when transplanting from the planting base to the flowerpot, the nutrient supply between the root and the branches and leaves is out of balance, especially for the bonsai with luxuriant branches and leaves. the evaporation of the leaf surface is greater than the absorption of the root system, and the top leaf curls and dries when the potted soil remains moist, so it is best to prune the branches and leaves properly to reduce the moisture of the branches and leaves. Excessive consumption of nutrients should restore root growth as soon as possible, and at the same time, watering should be controlled to keep the basin soil slightly dry, so as to facilitate root growth as soon as possible and speed up the restoration of normal nutrient supply. At the same time, Taxus has strong sprouting ability, especially the new branch growth ability is strong and resistant to pruning, and it will sprout new branches and leaves soon after survival. When necessary, plant rooting or rooting enhancers can be used to irrigate the basin soil every seven days or so, and continuously irrigate three or four times (using good quality products and not too much water) so that the roots can grow quickly and healthily. Restore the supply balance between roots and leaves as soon as possible, and make the yew grow well.

Third, as the yew bonsai is planted in the flowerpot with limited nutrients, it can only provide about half a year for growth, or now the plant shape is larger and the nutrient consumption is very large, so it is suggested that consumers had better replace the original pot as soon as possible after purchase. Because our company for bonsai for more than a month of re-bonsai, and stored in the distribution company for a period of time, plus yew like rich and loose soil. It is best to change the basin as soon as possible, when changing the pot to calculate the inner diameter of the flowerpot, the inner diameter of the new pot should be at least five centimeters larger. Before the new buds germinate in February and March every year, pour out the tree and the pot soil together when the basin soil is not dry or wet. Try not to break the original soil ball, if you find that there are too many roots after survival, you can properly cut off the bad roots, put the tree in a new basin, fill it with nutritious soil and press it gently, and only close the soil and roots in the basin can you improve the survival rate. otherwise, the plant is not easy to survive or does not grow vigorously. However, the soil should not be pressed too firmly, if the air cannot be breathed from the roots, the roots will rot and the plants will die. Water thoroughly immediately after planting. And leave the basin in the shade for a few days. After watering, the basin soil can no longer be turned over and pressed, otherwise the basin soil is easy to consolidate, or the soil is too solid and breathable and easy to cause rotten roots.

Fourth, the fertilization method of yew bonsai: nitrogen, phosphorus and potassium fertilizer, nitrogen fertilizer can promote the growth of flowers and plants; phosphorus fertilizer can promote the formation of flowers and fruits; potassium fertilizer can promote stem and root growth.

Because the bonsai is in a limited bowl space. Limited cultivation soil, organic matter is broken down into inorganic salts by bacteria and absorbed by roots. With the consumption of Taxus growth, the nutrients in the basin soil are gradually lacking, resulting in insufficient demand for growth. Although the prepared nutritious soil is used in the bonsai, do not apply fertilizer within three months after buying it back. As long as every seven to ten days, pour about 1000 times of potassium dihydrogen phosphate solution or foliar spray in the evening. Control the amount of water and don't water too much. Only when the leaf color becomes pale, the plant is thin, the leaf is yellowish white, the leaf tip appears "dry burning edge", and the leaf senescence occurs prematurely, apply 1000 times liquid urea and potassium sulfate 800x instant high quality compound fertilizer solution to remove sediment and then irrigate the basin soil. once every other month or so, it is best to use fully mature light bean cake fertilizer water (about 10% 15%) to avoid the tree trunk and apply along the basin wall as far as possible. Apply once a month. Pour clean water again the next day after fertilization, in case the fertilizer is too thick and dilute, the above two fertilizers can be used alternately, or you can dig two small pits in each basin and put five or six grains of urea and seven or eight grains of high-quality compound fertilizer in it. Then cover the soil and water it to dissolve the fertilizer. Taxus bonsai is not allowed to apply raw fertilizer and thick fertilizer. Topdressing should be based on nitrogen and phosphorus fertilizer, not too thick.

Fifth, the watering method of bonsai: the principle is "do not dry, do not water, water thoroughly"

Water is an important part of flowers and trees, all life activities of flowers and trees should be carried out with the participation of water, whether photosynthesis or transpiration, can not be separated from water, water can maintain the swelling and pressure of cells and make branches and leaves straight. But beyond the limit, the plant growth is thin and weak, such as long-term basin soil too much water, it will cause leaves yellowing, deciduous leaves, rotten roots, and even death.

1. Look at the slightly lighter color on the surface of the basin soil, the leaves slightly curl, press the basin soil with your fingers and feel a little soft, and when the sound from tapping the middle and upper part of the basin body with finger joints is relatively dull, the basin soil does not need to be watered, as long as the leaf surface is sprayed to replenish the moisture of the leaves. When the surface of the soil is white, press with your fingers and feel that the soil is hard, and there is a circle of cracks between the basin and the soil, when tapping the middle and upper part of the basin with finger joints gives a clear sound of "bang bang", when the young leaves of the new shoots are withered, the basin soil should be watered. The cracks between the soil and the basin should be compacted with hard objects before watering, and then poured with a large spoon. When pouring water, the spoon should be close to the edge of the basin, and the spoon should be poured in all at once, so that the basin soil can absorb enough water. If you pour a small amount of water into the basin for a while, you can see that the water flows out quickly from the bottom of the basin, indicating that the soil and the basin are not completely compacted. The gap between the basin wall and the soil is pressed and then poured by the application object. When the basin soil structure is normal, it is better for water to seep out slowly from the bottom of the basin for about 40 seconds to one minute after watering. The water temperature must be close to or consistent with the air temperature at that time. When using tap water, you should first put the water in the sun for about three hours before watering, because the light helps to decompose the oxides in the tap water and increase the water temperature. You can also put the water in the big basin for half a day or one night and then water it. If there are many bonsai, you'd better put the water in the big tank to make the water temperature as close as possible to the air temperature and soil temperature. Especially in the hot season, in addition to watering the basin soil, it is also necessary to spray water spray on the leaves to keep them moist for growth. When the basin soil can be kept a little dry and not too wet, each basin must be checked in the light of the actual situation, and be careful not to water too much.

2. The evergreen leaves of Taxus chinensis var. mairei are suitable to be placed indoors. However, the yew bonsai is not easy to be placed in the air outlet of the air conditioner, otherwise it will increase the water evaporation of the yew leaves, easily cause the branches and leaves of the yew to dehydrate quickly, and cause the leaves to curl and dry up. If you turn on the air conditioner in the air conditioner room every day, you should spray the foliar surface every day to maintain the foliar humidity and put a basin of water indoors. In the room with heating in winter in the north, the heat sink should be dispersed far away, and a basin of water should be put on the radiator to increase the indoor air humidity. Summer and autumn temperature more than 30 degrees Celsius should strengthen shading and cooling work, can be moved to the north ventilated room. Spray water to cool down when necessary to create a cool, moist environment to facilitate the growth of the yew. And avoid the western sun shining directly on the room on the yew bonsai. The watering amount of bonsai should be controlled in winter to avoid long-term over-wetness of potted soil, because the plant growth is not exuberant in winter, the volatile water of leaves is less, if the potted soil is too wet for a long time, the surface of potted soil will be hardened and impervious, and it is easy to cause rotten roots. The yew must pay attention to the indoor ventilation when raising the yew indoors.

3. The soil for yew planting should be loose, humus-rich, fertile and slightly acidic (between PH=5.5~7). Tea water can not be poured into the yew bonsai. If you often pour the rest of the tea water, because the tea water contains theophylline and other alkaloids. If the pH of the soil is changed for a while, it will also destroy the organic matter nutrients in the soil. It can inhibit the growth of Taxus and cause excessive soil moisture, hinder the ventilation of basin soil, and cause root rot and stem rot. When there are conditions for a week or so, moving the yew bonsai to the balcony in the evening to receive dew and exposing it to the sun for about one or two hours in the morning (before 10:00 in the morning) is beneficial to the growth of the yew and improve its disease resistance. In summer and autumn, it is necessary to prevent the western sun from shining directly on the yew through the window, so as to prevent the high temperature burning leaves from affecting the ornamental value.

VI. Pay attention to the main points

1. The yew should pay attention to the adjustment of light because the tree is small, so it needs light, but it can not be placed in the strong light for too long. Generally, it can be basked in about two hours before ten o'clock in the morning or after five o'clock every day in summer and autumn. Usually accept more scattered sunlight. Otherwise, the leaf tip will be scorched yellow due to strong light burns, and the indoor ventilation will be maintained, so that the indoor air will not be withered, sagging and other bad growth phenomena.

2. If the young leaves of the new bonsai appear dark yellow and dull, the withering phenomenon of the top of the new shoot is generally caused by overwatering too much soil and impermeable so that part of the roots rot and absorb water. When the ability to absorb fertilizer is weakened, the amount of water should be controlled if the symptoms are mild, and the basin surface soil should be gently loosened with hard and blunt objects to make the basin soil breathable, move to a place that can accept dew every night, and move to a shady place at eight or nine o'clock in the morning, which is conducive to the healthy growth of the root system. If the leaves are yellowed and curled in a short period of time, it means that the root rot is serious, because immediately turn the basin to check the root rot condition, (the normal fibrous root shows a full white shape), if more than half, generally save not alive.

3. Yellow leaves occur in the old leaves from the bottom up, but the new leaves generally grow normally, which is generally caused by the lack of water in the roots and the lack of water in the roots. Sometimes the top leaves dry and curl, touch the dry leaves fall, but the old leaves grow normally, generally caused by the lack of water in the roots, should be watered thoroughly at one time. When watering, the cracks on the edge of the basin must be compacted with objects to prevent the water from quickly leaking from the cracks. To create the illusion of being thoroughly watered, the roots will die due to lack of water over a long time. Move outdoors at night to accept more rain and dew, and receive two hours of sunshine in the morning and evening to restore the growth of the yew.

4. Taxus is suitable for weakly acidic soil. If it is irrigated with alkaline water for a long time, it will cause leaves to change from green to yellow, or even leaves to fall off, due to the addition of acidic nutrients or spraying leaves or watering basin soil with 2/1000 ferrous sulfate solution, once every ten days, three times in a row. It can make the leaves turn green due to alkali yellow.

5. In March and April every year, the yew will sprout a large number of buds and consume a lot of nutrients. At this time, the buds growing toward the inside can be removed to prevent the leaves from yellowing or falling off because the branches are too dense and unventilated. For cross branches, inward branches grow and cut sparsely, which can improve ventilation. Transparent light, and can save the excessive consumption of water and nutrients, it is best not to spray liquid fertilizer on the leaf surface at the beginning of bud germination, or to pour thick fertilizer on the root.

6. if the normal amount of fertilizer is applied with urea alone, the concentration of nitrogen fertilizer is generally 1/1000, and if potassium dihydrogen phosphate is used alone, the concentration of phosphate fertilizer is 1/1000 to 2/1000, with an interval of seven to ten days.

Selection of afforestation land

The middle and lower part of the hillside, the foot of the slope, Caogou, the shady slope of Shanwan and the slope is less than 35 degrees, the soil ph value is 4.5-7.0, and the land with high fertility, high moisture and good drainage can be used as forest land. The artificial young forest land with canopy density less than 0.4 can also be used for afforestation.

Land preparation

Banded or burrowed ground preparation. The specification of the acupoint is 40cmx40cmx30cm (length x width x height). Different land conditions can be combined with soil preparation and fertilizer application according to the situation of land fertility.

Afforestation density

1100 / mu. Row spacing 60x400cm (Hengshan x Shunshan). The density of afforestation in the young plantation should be determined according to the actual canopy condition of the young forest, and the principle is to plant it in the open space with good light conditions outside the young canopy.

Afforestation time

From February to April in spring and from September to November in autumn.

Operation and management

It should be nurtured 2-3 times a year after afforestation. Hoe and caress twice in May-June and August-September, and knife caress in July. After afforestation, it was combined with hoing and topdressing in May every year from the second year. From the fourth year after afforestation, raw materials can be harvested by pruning branches and leaves, or whole plants (including roots) can be dug up every year to extract paclitaxel. For greening, it needs to be trimmed according to the shape.

The control of stem rot of Taxus chinensis var. mairei by diseases and insect pests is one of the most serious diseases in the growing period of Taxus cutting seedlings. After 2 months of cutting, stem rot occurred successively at the stem base of the cuttings (at the junction of underground and aboveground cuttings), which was caused by individual plants and then spread into a whole cluster, resulting in green loss, death and shedding of panicle leaves. Because the disease mainly occurs in the high temperature season in summer and autumn, the cutting seedlings are damaged by high soil temperature, which provides conditions for the invasion of pathogens. The occurrence and epidemic of the disease mainly depend on the air temperature in July and August. If the disease occurs early, the heat resistance of seedlings is weak, the disease is serious.

Prevention and cure measures

First, to reduce the soil surface temperature of the nursery bed during summer and autumn to prevent the base of the seedling stem from being burned, so as not to cause the wound to lead to the invasion of bacteria.

Second, apply more fertilizer to promote the growth of cuttings and enhance their disease resistance.

Third, using pentachloronitrobenzene powder + dimethazone powder mixed with water to irrigate with 5g/ kg concentration, the best control effect reached 89%, or with carbendazim + methyl thiophanate wettable powder mixed with water with 4g/ kg concentration, the control effect reached 83%.

4. the occurrence of stem rot of cutting seedlings can be basically controlled by alternating application of the above two methods to control the disease in a large area.

7. Main value

Economic value according to the report of the fifth edition of People's Daily on October 17, 2001, the price of high-quality paclitaxel in the international market in 2000 was as high as 180000 US dollars per kilogram.

Heartwood orange-red, sapwood yellowish brown, straight texture, fine structure, specific gravity 0.55-0.76, solid and durable, less cracking after drying. It can be used for construction, vehicles, furniture, utensils, agricultural tools and stationery.

Medicinal value of Taxus the main medicinal value of Taxus is its extract-secondary metabolite-paclitaxel. Paclitaxel is the first anti-tumor component isolated from the bark of Taxus chinensis var. mairei. It is one of the best drugs for the treatment of metastatic ovarian cancer and breast cancer. it also has a significant effect on lung cancer and esophageal cancer and can significantly inhibit glomerulonephritis and parvovirus inflammation.

The roots, stems and leaves of the yew can be used as medicine to treat dysuria, eliminate swelling and pain, and have therapeutic effects on diabetes, irregular menstruation and increased blood volume. Taxus can also be used for postpartum recuperation and has a certain therapeutic effect on female diseases.

Landscape ecological landscaping

In landscaping, indoor bonsai also has a very broad development prospects, such as the use of rare yew trees to make high-grade bonsai. The bonsai shape of Taxus mairei treated by dwarfing technology is simple and elegant, the branches and leaves are compact but not dense, stretched but not loose, red stem, red branch, green leaf and red bean make it have multiple ornamental value of stem, branch, leaf and fruit.

Purify the air

Taxus can well purify the indoor air, absorb the indoor poison gas such as formaldehyde during the decoration of the new house can be well absorbed, and reduce the content of poison gas indoors. The yew itself can absorb carbon dioxide and release oxygen. It is a natural oxygen bar that can be used day and night. It belongs to the CAM tree species, which can prevent respiratory diseases and keep the air clean and safe. It has been proved by modern environmental monitoring that yew can absorb many poisonous gases such as sulfur dioxide and carbon monoxide into the body and purify the indoor air.