Among the diverse exotic species of trees, eucalyptus is considered one of the most interesting and famous in the whole world. Many consider them able to grow exclusively in Australia and New Zealand close to this mainland, but some species feel good in the warm climatic zones of the Northern Hemisphere.
The genus of eucalyptus trees is very extensive, includes numerous varieties of evergreen hard-leaved trees and shrubs and belongs to the myrtle family. In Russia, they are often called gum because of the characteristic influxes on the bark or shameless for the ability of trees to dump bark. The scientific name eucalyptus - hiding - was given to the plant genus because of flower buds hidden by the sepals.
Spread
Eucalyptus plants are giant plants. Many of them during their life reach the size of a skyscraper, the highest tree in the world is considered to be a tree in the forests of Tasmania: its growth is 101 m - several times higher than that of many recognized giants. However, this is not the limit, biologists have so far unconfirmed verbal descriptions of giants with a height of 150 m.
The birthplace of most species - several hundred - is Australia and nearby islands, where these myrtle account for almost 90% of all forests and groves. Some species are found in the tropics and subtropics of southern France, Portugal, Greece, India, southern China, Malaysia, Israel, Crimea and other regions with a warm and humid climate; they prefer well-lit areas. Eucalyptus plants grow on nutrient, slightly acidic or neutral soils, but many adapt to sandstones, podzolic soils and loams. They tolerate short-term flooding.
Species found in mountainous areas are frost-resistant, but many are still afraid of cold weather and quickly die at sub-zero temperatures.
"Trees" with a height of more than 50 m are far from rare among eucalyptus trees. By the type and structure of the bark, several types of trees are distinguished: smooth-bark, iron-bark, scale-bark, fiber-bark, peppermint. The bark of many of them in the process of growth falls away from the trunks in pieces or entire layers, exposing the deeper layers. By this property, eucalyptus is similar to a plane tree, also dropping sections of the cortex. The color of the surface of the bark of one tree can change over the years, the trunk often combines bright green, yellow, red and purple areas. A vivid example of such multi-redness is that of a rainbow eucalyptus growing in tropical Philippines and Indonesia.
Botanical Description
Tree trunks can be straight or curved, with a large number of branches. Very often, their surface is covered with gum - viscous compounds of mono - and polysaccharides. Branches form hipped, rounded, pyramidal or cylindrical crowns. The root system of myrtle is powerful, developed, able to penetrate to great depths.
The leaves of eucalyptus trees are opposite or alternate, covered with a wax coating, have several stages in development. Young - more tender, relatively small, cordate or rounded, gradually discarded. Transition thicken, increase in size, change color. Adults often become elongated lanceolate, sometimes curved in the form of sickles, rough, pointed at the ends, silver-green or bluish. The eucalyptus tree, despite the dense crown, almost does not give shade, since the leaf blades of it are located in the same plane with the branches, without forming barriers to sunlight. The intercellular glands of the leaves contain essential oil.
In Australia, a beautiful marsupial animal, a koala, lives in the branches of trees. Leaves are the only food for him, which is noteworthy, because fresh greens contain many toxic substances, including hydrocyanic acid.
Eucalyptus bloom in different seasons, depending on species aged 2-10 years. From the period of swelling of the kidneys to ripening on the branches of the fruit can take from several months to several years. The flowers are small, white, yellow, orange, pink or bright red, collected in inflorescences of a thyroid, panicle-shaped or axillary umbrellas, bisexual (with a stamen and pestle). The various species growing next to each other are cross-pollinated, resulting in hybrids sprouting. Fruits are smooth or furrowed, conical or rounded capsules with a large number of small seeds. Their weight is microscopically small: 1000 pieces are only 1–2 g.
Features
A characteristic feature of eucalyptus trees is extremely rapid growth: many species during the first three years of life reach a height of 10 m, in the next few years they can grow to the size of a 15-storey building. Adult eucalyptus is rarely found below 30 m. In this case, the diameter of the trunks remains relatively thin - about 30 cm. A noticeable increase in thickness begins in trees from 15–20 years of age, and extension in height slows down. Adults and old specimens are capable of reaching several meters in the trunk section.
The great vitality of eucalyptus trees is also known: in case of serious damage or even after burning in fires, trees quickly regenerate, overgrowing with new shoots for several months.
The unique features of eucalyptus trees, their decorative qualities make these trees attractive in the eyes of florists and landscape designers, and the ability to form hybrid varieties and rapid growth force biologists and breeders to develop new forms that are resistant to various environmental conditions. Species such as cineria and populus (topoid), are compact in size and can be grown as houseplants, and their beautiful picturesque branches with silver-green or bluish foliage - serve as material for the preparation of holiday bouquets.
Given the ability of eucalyptus trees to grow rapidly, their cultivation is practiced using seeds and vegetatively. Under favorable conditions, greenhouse seeds germinate after 5 days. Cuttings of trees are allowed to be transferred immediately to the open ground.
Benefit and application
Eucalyptus trees are often planted in marshy areas for the purpose of drainage, since it is believed that their powerful roots act as pumps that absorb water. In addition, these trees are able to prevent erosion and weathering of soils, strengthen the steep slopes of ravines.
Healing properties
The essential oil contained in the leaves of eucalyptus is highly regarded in the pharmaceutical industry, cosmetology and traditional medicine. Their saturation is most of all in the spherical greenery. A viscous slightly greenish or colorless liquid with a pungent odor resembling menthol is widely known for its antimicrobial and anti-inflammatory properties. TThe therapeutic effect is due to the presence of cineole, phytoncides, tannins and organic acids in its composition. On the basis of eucalyptus ester, funds are created to relieve symptoms of radiculitis, neuralgia, joint diseases, to get rid of fever, to treat bruises, ailments of the upper respiratory tract, acute respiratory viral infections, cough, rhinitis, gum disease, and to relieve pain during stings of stinging insects.
The infusion of leaves is washed with scratches, wounds and skin ulcers, it is used for compresses for dermatitis and eczema.
Eucalyptus oil is added to shampoos, toothpastes, lotions, balms. Its pleasant pungent aroma gives strength and vitality, scares away bloodsucking: mosquitoes and mosquitoes. Bath brooms from thin branches of eucalyptus are especially appreciated - in a hot, humid environment, the escaping ether vapors perfectly clean the mucous membranes and skin.
Building materials
Eucalyptus wood belongs to sound species, its sapwood is usually very narrow and not widely used. Trees reach technical maturity by 20–25 years. The natural color of lumber, depending on the type, is white, pink, gray, brown, light red or almost burgundy. Over time, fresh timber darkens under the influence of air and sunlight. The vessels of the rock mass are scattered and small. Eucalyptus is very capricious in drying: it is prone to cracking and warping, it dries out very much, but the wood that has undergone pre-treatment is very durable and stable. The density of the material varies from 700 to 900 kg / m³ and is comparable to oak.
The fibers of the array are straight-layered, having tangled or wavy folds, which can create certain difficulties in processing tools. The material is cut and bent well, the surface holds paints, polishing and glue. Various impregnations penetrate into the depth with difficulty due to the high density, but this is offset by good biostability. Eucalyptus is almost not damaged by pests and is very resistant to mold damage.
Widespread and rapid growth make eucalyptus wood available for various industries, it is not considered an expensive variety. The main industries using this raw material include: paper, fuel, shipbuilding and engineering. From eucalyptus make building beams, sleepers, erect technical buildings, fences, hydraulic structures. It is an excellent material for the manufacture of furniture, floor coverings, wall partitions, window frames, doors, and furnishings.
High strength, the presence of wood with an interesting natural pattern, susceptibility to coating with varnishes and paints allow the use of eucalyptus for the manufacture of various decor items, toys, souvenir products.
In Russia, eucalyptus wood remains unclaimed due to its exotic nature; the price of 1 m³ of lumber is about 100,000 rubles.