Evergreen tall trees (a few species are small trees) can grow to100-100 meters, and the highest is 156 meters, which is the tallest tree in the world. Like light, like humidity, drought resistance, heat resistance, cold resistance, very sensitive to low temperature. Some species originated in the tropics and cannot tolerate low temperatures below 0 degrees; Some species are native to a warm climate and can withstand a low temperature of-10 degrees. Most require the annual average temperature to be above 65438 05℃, and the most Leng Yue is not lower than 7 ~ 8℃. The general name of eucalyptus plants in Myrtaceae. Evergreen tree with thick and durable bark or smooth bark, which falls off every year. There are two types of leaves, the young leaves are sessile and opposite, and the mature leaves are sickle-shaped or oblong. There are volatile aromatic oils. Flowers bisexual, calyx tube bell-shaped, ovary connate; Petals and calyx lobes form a cap; Stamens are numerous, anthers are heart-shaped or kidney-shaped, straight split or perforated; Disk exists; The ovary is inferior, with 2-7 cells and many ovules. The capsule is hidden in the pot-shaped calyx tube or protrudes outside the calyx tube; The disk forms a fruit margin when it bears fruit. There are many seeds, but few can be bred. There are 522 species of eucalyptus, 150 species.

Born in sunny plains, hillsides and roadsides. Recyclable holidays every year. It is cultivated in the south and southwest of China. Eucalyptus has a small crown and high light transmittance, which is beneficial to the growth of grass under the tree. It is a water-saving tree species with small crown and small transpiration. It can grow in all kinds of soils, and most soils can adapt to acidity and alkalinity. The most suitable soil is fertile alluvial soil. Generally, it can grow in areas with annual precipitation of 500 mm, and it grows better when the annual precipitation exceeds1000 mm. It is suitable for growing in acid red soil, yellow soil and alluvial soil with deep soil layers, but it grows better in places with deep soil layers, loose soil layers and good drainage. The main root is deep and has strong wind resistance. Most roots and necks have wood tumors, which can store nutrients and germinate and renew. Generally, it can blossom and bear fruit in 3 ~ 4 years after afforestation.

value

Eucalyptus is graceful, evergreen all the year round, growing extremely rapidly, and has the ability to sprout, renew and improve wetlands. Tree species suitable for landscaping. The leaves contain aromatic oil, which can sterilize and repel mosquitoes and can be used to extract sesame oil. It is also a good greening tree species in convalescent areas, residential areas, hospitals and public green spaces. The twigs and bark contain tannin, which can be used to extract tannin extract; Bark and wood can also be used to make pulp. Eucalyptus is an important honey source plant with long flowering period and large honey flow. Eucalyptus wood has many properties, generally tough and durable, and can be used as materials for sleepers, columns, bridges, buildings, pulp and wood-based panels. Leaves can be used to extract essential oil to produce cineole, citral and so on. , widely used in perfume and pharmaceutical industries. The bark, wood and leaves of many eucalyptus trees contain tannin, which can be used as scale remover and retarder for boilers. In addition, eucalyptus is also a good fuelwood, honey source plant and greening and shelterbelt tree species.

Eucalyptus has a small crown and high light transmittance, which is beneficial to the growth of grass under the tree and to insects and birds. It is a water-saving tree species with small crown and small water evaporation. CCTV-7 agricultural programs have made relevant reports, clarifying everyone's misunderstanding of eucalyptus.

Eucalyptus is regarded as an auspicious plant in the gardening art in China. Like banyan trees, it is said that "adults plant big trees, and big trees raise adults." Young people plant this tree, and when it grows into a "giant" on a 30-story tree, it will become the patron saint of tree planters and the dragon among people.

Eucalyptus has many uses and many benefits to Australia, the origin of eucalyptus. It is also reasonable to say that it absorbs a lot of water and will cause the water source to dry up; Rapid growth and rapid absorption of nutrients will lead to poor nutrients in the land and other plants cannot grow. So where eucalyptus grows in large quantities, there will be few other tree species. Eucalyptus can kill bacteria and repel mosquitoes at the same time, so there are no insects that feed on mosquitoes and no birds that feed on insects. Therefore, eucalyptus planting must be done according to our abilities and treated with caution.

Eucalyptus is a light-loving tree species. The wood is red, shiny, without special smell, with staggered textures, dense structure, hard and heavy materials and easy bending, which is very suitable for bending wood. Can be used as furniture, floors, lathes, tool handles and farm tools. Its fiber is a good raw material for papermaking, which has a high combustion value of small diameter wood, can be used as fuel and has a wide range of uses.

As one of the three famous fast-growing tree species in the world, it has strong adaptability, diverse tree species, wide uses and high economic value. It is a very rare short-term industrial timber tree species, which can be harvested and utilized in 5-8 years.

Characteristics of eucalyptus:

1, growing rapidly. Eucalyptus is the fastest growing tree species in the world. In peak season 1 day can grow 3 cm, one month can grow 1 meter, and one year can grow1meter. Brazil has the best eucalyptus plantation in the world, with the highest growth rate of 7. 8 cubic meters per year. Mu, the highest growth rate of China's experimental forest in Hainan reaches 4 cubic meters/year. Mu.

2. The rotation period is extremely short. The rotation period of Picea koraiensis plantation is 70 years. The rotation period of Pinus massoniana plantation in China is 20-25 years, Chinese fir plantation is 15-20 years, while eucalyptus plantation in southern provinces is 5-7 years, especially in Leizhou Peninsula, and some of them are even shortened to 3-4 years. Because of its rapid growth, the wood produced is mainly used to make wood chips as raw materials for papermaking or fiberboard industry. Therefore, the business model of short-period small-diameter timber is very popular.

3. Mature technology. Eucalyptus has strong adaptability and is suitable for intensive management and high-yield cultivation. At present, Eucalyptus is widely planted all over the world and has a set of mature cultivation and management techniques. As long as the varieties are suitable and the measures are in place, high yield can be obtained.

4. Less pests and diseases. As eucalyptus is an exotic tree species, it has not been planted for a long time in China, and there are few pests and diseases in a large area, which is much better than poplar. However, in recent years, the situation of pests and diseases has a tendency to expand and develop.

5. Good economic benefits. Eucalyptus plantation is the best economic benefit in China's forestry industry at present. Take Zhanjiang as an example, the net profit of eucalyptus planting can reach 200 yuan -500 yuan/year. Mu, in recent years, the price of eucalyptus chips has been rising, forestry taxes and fees have been declining, and afforestation profits have been getting better and better. Here, some people are willing to rent land to plant eucalyptus at the price of 100 yuan/mu, which shows that eucalyptus plantation is profitable.

If you want to plant, here is a hint:

Eucalyptus likes warm climate, but it is not resistant to damp and heat, the climate is overheated and it grows poorly. Yunnan is mainly distributed at an altitude of 1200-2400 meters, with weak cold tolerance and can only bear the low temperature of -7℃ for a short time. If it is kept at -5℃ for 2-3 days, it will cause different degrees of freezing damage, ranging from twigs to whole plants. Eucalyptus likes light, and a little shade will affect its growth rate. I like fertile and moist acid soil. In a good environment in Kunming, the seedlings of 1.5-2 years old can reach 1.5-2 meters high, the seedlings of 3 years old can reach 9 meters high, and the seedlings of 10 years old can reach 20 meters high. The seedlings of 20 years old grow slowly and can blossom and bear fruit after 6 years old. 15 years old.

sow seeds

Seeds should be collected in February (1 1- 12) and sown in the following spring. Seeds can also be collected in July and August and sown that year. You can get10.5 kg seeds per 100 kg fruit, with a 1000-grain weight of 2.8 g eucalyptus globulus and10.5 g eucalyptus globulus. The germination rate of seeds is above 90%.

1. Choose a vegetable garden with fertile soil as a seedbed, sow in mid-March, and finely adjust the geographical moisture, with the moisture width of1.2-1.6m.. After soaking the seeds for 48 hours, mix them with fine sand and sow them on the seedbed, and cover them with fine manure with a thickness of 1-2 cm. Cover with film after pouring enough water, and it will be unearthed in 7- 10 days after sowing. Keep the soil moist and ventilated to prevent seedlings from being burned at high temperature. When the seedlings grow to a height of 5- 10 cm, the film is uncovered and the seedlings are tempered; When the seedlings grow to 30-40 cm high, they should be transplanted in rainy days, which is easy to survive. The best transplanting time in central Yunnan is from early June to early July.

2. Nursery seedlings in nutrient bags. After the nutrient soil is bagged, sow the soaked seeds into the bag (2-3 seeds per bag), then cover it with a layer of fine manure, then cover it with water, and pay attention to ventilation and moisture retention. Fixing seedlings during seedling growth, pulling out weak seedlings, and keeping 1 plant in each nutrient bag. When the seedlings grow to 10-20cm, they can be transplanted. Generally, seedlings are raised in early March and transplanted in rainy season in early June.

3. Seedbed management. After the seedlings emerge, pull out all weeds in the seedbed. Eucalyptus seedlings are prone to collapse. At the early stage of the disease, the seedbed was sprayed or watered with 70% Pinus elliottii solution 500 times (per mu 100 kg liquid medicine) for 2-3 times with an interval of 10- 15 days.

1, transplant. Transplanting will be carried out after the rainy season begins in early June. The pond is 40 cm deep and 40 cm in diameter, and 300 plants will be planted per mu (plant spacing1× 2m). After planting, sufficient root-fixing water should be poured to raise the soil above the surface to prevent the roots from rotting and the soil from hardening, which is beneficial to the survival and growth of young trees. 2. Fertilization and pest control. After surviving, apply 50 kg of compound fertilizer or 40 kg of ordinary calcium superphosphate and urea 10 kg around the pond. Eucalyptus is vulnerable to yellow ants. After transplanting, 500 grams of diazinon particles with 10% or 3% phoxim 1 kg per mu are mixed into the chemical fertilizer and applied around the pond to mix with the soil to prevent the harm of yellow ants.

3. Young tree management. After survival, young trees are forbidden to graze, and weeds around the seedlings should be shoveled and hoed in time, and the soil should be loosened if possible to keep the soil loose. Prune 1 time every year after the seedlings grow to 2-3 years, and prune the weak branches at the lower layer, which is beneficial to ventilation and light transmission and maintain the growth of seedlings. After 4 years, leaves can be picked to extract aromatic oil.

4. Management and protection. After afforestation, a special person should be arranged to take charge to prevent human and animal injuries within three years.

5. parenting. Tend to be twice. For the first time, one month after afforestation, it is necessary to cultivate soil, loosen soil and weed. In June of the following year, it was required to shovel grass, remove sprouting and expand holes. The hoeing depth is greater than 10 cm. Because eucalyptus is naturally pruned, there is generally no need for manual pruning, so as to avoid leaving scars on the trunk, resulting in poor trunk shape; When the advantages of individual tips are not obvious or there are more than two damaged branches at the top of seedlings, pruning and shaping should be carried out to promote the formation of trunk.

The common pests of eucalyptus are soil-dwelling termites, mainly black-winged termites, followed by yellow-winged termites. Although other ant species have been found in the forest, they are not enough to cause harm.

1. Danger Law. In the young eucalyptus forest, termites first harm the root neck, then gradually transfer from the soil layer to the surface and aboveground parts, and then peel off the cortex of the main root, the inverted root and the base of the trunk along the surface soil, so that the nutrients of the young tree can not be transported up and down and die. In severe cases, a layer of "mud quilt" is built above and below the trunk to wrap all the branches of the trunk, so that the appearance of each young tree looks like "clay sculpture", and termites peel off the phloem of eucalyptus in the "mud quilt" to expose the xylem, resulting in the death of the tree.

2. Prevention methods. In priority cases, drug bait is used to trap and kill.

(1) During afforestation, 3-4g carbofuran is mixed with base fertilizer and soil to fill holes, and the dosage is 0.35kg per mu.

(2) After afforestation, apply 2 grams of carbofuran (carbofuran) around the stump at a horizontal distance of 5, and use 0.22 kg per mu. Be careful not to let the powder come into contact with the seedlings to avoid phytotoxicity.

afforestation

1, afforestation site selection. Choose barren hills suitable for forest with convenient transportation, gentle slope, deep soil layer and loose fertility below 600 meters above sea level.

2. Soil preparation. The size of the hole is 40×40×40 cm.

3. Density. Plant spacing: 2× 3m, per mu 1 12 plants.

4. Apply base fertilizer. Within half a month before planting, the top soil should be used to return to the hole height 10 cm, and then 0.5 kg of phosphate fertilizer should be applied to each plant. Note that phosphate fertilizer should be removed evenly and not piled up, and then fill the pit with soil to the soil surface.

5. seedlings. It is required that the provenance is pure and the seedlings are of the first grade. ..

6. Planting. Eucalyptus seedlings are planted on the mountain. Because the seedlings are tender, special care should be taken in transportation and planting. When planting, you should first remove the nutrient bag, hold the nutrient soil by hand, carefully put it into the hole, then cover the soil, compact it from the side, and then compact the root of the seedling with fine soil, just enough to cover the nutrient soil. Finally, cover the surface with 3-5 cm fine soil to form a turtle back shape to prevent water accumulation in rainy days.

7. Top dressing. Top dressing 3-4 times a year. The interval should not be too short or too long, generally every 2-5 weeks. Top dressing with nitrogen fertilizer has a great influence on the quality of seedlings. In order to improve the resistance of seedlings to low temperature and drought, top dressing should be completed 6-8 weeks before frost comes. After the first afforestation 1 month, combine weeding seedlings with topdressing urea in rainy days, and apply 3-5g urea to each plant, and circle at a horizontal distance of 5 cm from the seedlings. When fertilizing, we should guard against death. The second time, each plant is 6-10g; The third time was 6- 10g/ plant; For the fourth time, more than10g urea was applied to each plant. Finally, cover a layer of fine soil with a thickness of 5-7 to prevent fertilizer loss.