What Is Eucalyptus Globulus?

Eucalyptus robusta Smith ( Eucalyptus robusta Smith ), also known as Eucalyptus, is a collective name for Myrtaceae and Eucalyptus. Evergreen tall trees, about 600 species. Evergreen plants have periodic dead leaves falling off within one year. Most species are tall trees, a few are small trees, and they are rarely shrubby. The shape of the canopy is spire, branched, and weeping. Leaves simple, entire, leathery, sometimes covered with a thin layer of waxy. The leaves can be divided into three types: juvenile leaves, middle leaves and mature leaves. The leaves of most varieties are opposite, smaller, heart-shaped or broad-lanceolate.

Grows on sunny plains, hillsides and roadsides. Leaves can be collected throughout the year. It is cultivated in southern and southwestern China. The trunk is tall and the root system is developed.

There are types of dry hard-leaf tree forests, wet hard-leaf tree types, savanna types, dry hard-leaf tree types, and alpine meadow types.

Eucalyptus species are diverse, with 522 species and 150 varieties. Eucalyptus, direct-dried eucalyptus,

Eucalyptus citrus, Eucalyptus grandis and Eucalyptus esculenta.

By sowing, grafting,

Although eucalyptus has a fast growth rate and a wide range of wood uses, the biological characteristics of eucalyptus have been criticized by experts and scholars in the broad forestry circle. The rapid growth of eucalyptus is accompanied by the deterioration of the local ecological environment. During the growth process, a large amount of water resources are needed. Large-scale planting will cause the local groundwater level to drop and soil water retention capacity to decrease. In the long run, it will cause land consolidation and even soil desertification. Eucalyptus has a huge demand for fertilizer in the soil, and in areas where eucalyptus has been planted, land fertility will decline to varying degrees.

In the management of eucalyptus plantations, only planting and not applying are emphasized, the amount of fertilizer applied is insufficient, and the same formula has been used for many years.

In the management of eucalyptus plantations, there is a lack of understanding of the importance of eucalyptus fertilization and extensive management methods that focus on "planting" but not "fertilizing". Insufficient fertilization of a large number of elements of N, P, and K is common. Eucalyptus high-yield forests are calculated at a rotation period of 5 to 6 years, and the target yield is calculated as 150 m3 · hm-2. The target fertilizer required for total yield is pure N 125 g · plant-1, P2O548 g · plant-1, K2O 65 g · The eucalyptus fertilization rate in southern China is mostly pure N 50 ~ 80 g · strain-1, P2O510 ~ 30 g · strain-1, K2O 20 ~ 30 g · strain, far lower than the theoretical demand. It can be seen that the deficiency of N, P, and K elements in eucalyptus fertilization in China is widespread. In addition, in terms of medium and trace element fertilization, although most of the formula will be added with Ca, Mg, B, Zn, or Cu, but the amount of the addition lacks scientific basis and is highly blind.

There is a serious shortage of organic matter input in the recommended fertilization scheme, and the combination of land use and cultivated land has not been achieved

Eucalyptus fertilization is mainly based on chemical fertilizers. The input of humic acid carbon-containing fertilizers for improving the soil is seriously inadequate, and the negative effects brought by the large-scale application of chemical fertilizers threaten the sustainable development of eucalyptus forests. Basically, fertilization schemes have been proposed in eucalyptus major provinces and regions.For example, the best formulas for the basement fertilizers in the mountainous areas of Guangdong and Guangxi are: calcium-magnesium-phosphorus fertilizer 400 ~ 500 g · strain-1 + Russian compound fertilizer 100 ~ 150 g · strain-1; Dry or high temperature disinfected dry chicken manure 1 000 g · strain-1 + imported compound fertilizer 100 ~ 150 g · strain-1; qualified eucalyptus special fertilizer 33% ~ 46% (N 15% ~ 18%, P2O510% ~ 15%, K2O 8% ~ 15%) 250 ~ 300 g · strain. The formula of the best-performing basal fertilizers in Fujian Province is: calcium magnesium phosphate 600 g · strain-1 + urea 200 g · strain-1 + potassium chloride 100 g · strain. With reference to the results of fertilization experiments in various places, the organic matter content of eucalyptus special base fertilizers developed by various fertilizer manufacturers is mostly 2% ~ 10%, and the total nutrient content is 25% ~ 30%, of which N 5% ~ 7%, P2O512% ~ 15%, K2O 8 % ~ 10%, trace elements 2% ~ 5%, fertilization amount is 300 ~ 500 g · strain-1.

It can be seen that most of the eucalyptus fertilizers in China have a serious shortage of organic matter input. Even though some eucalyptus plantation bases, forest farms or enterprises have attached importance to the importance of organic fertilizers, most of them still remain on the basis of simple mixing of manure and animal manure, sea mud, green manure, fired soil and other chemical fertilizers. Industrial production of organic-inorganic compound fertilizers containing a large amount of organic matter has not only led to a further increase in the labor costs of eucalyptus fertilization, but also heavy metals in organic fertilizers have caused continuous pollution and damage to forest soils. There are few studies on the application of nutritional diagnosis technology to eucalyptus balanced fertilization, no regional fertilization guidance has been formed, and the lack of forestry system soil testing formula fertilization schemes is still lacking.

The area of eucalyptus plantations in China is large, and the site conditions vary from place to place. There are no uniform standards in terms of fertilizer varieties, nutrient distribution ratios, and fertilizer selection. ^[3]

There are still some problems and contradictions in the development of eucalyptus in China, the main ones are:

(1) The production mechanism of the new strain is not perfect, and the development speed cannot keep up with the market development needs, resulting in a single eucalyptus planting line, which poses a great risk to the ecology, pests and diseases of the eucalyptus forest;

(2) The lack of stability and continuity of the government's encouragement policy has left growers confused;

(3) disputes between contracts and interests between the owner and the leaser of the woodland;

(4) The rapid development of eucalyptus is inconsistent with the development of other tree species. It has a "wood show in the forest, the wind will destroy it";

(5) A "predatory" approach to management has created a series of ecological and environmental issues. ^[4]