What are the characteristics of pine trees?

Pine is a plant of the genus Pinus in the pine family, which is not only of many species, but also widely distributed. it is a wheel-shaped branch, the internodes are long, the branchlets are relatively thin, straight or bent slightly downward, the needles are slender and elongated into bundles, and its crown looks like a loose pine. The word "pine" is the image description of its crown characteristics. Let's take a look at the characteristics of the pine tree.

The tree is big

Most species of pines are tall and straight trees, with a height of 45 meters and a breast diameter of 1.5 meters after maturity, with good materials and many pillars. Pinus koraiensis, the "king of wood" in northeast China, Pinus koraiensis, the tall tree species widely distributed in western North America, Pinus elliottii, and Pinus elliottii, which are widely distributed in the west and north of Eurasia, are famous timber species.

Many kinds

There are nearly 80 species of pine trees in the world. Such as Pinus tabulaeformis, Pinus sylvestris, Pinus tabulaeformis, Pinus elliottii, Pinus yunnanensis, Pinus elliottii, Pinus taibiensis, Pinus taiwanensis, Pinus elliottii, Pinus elliottii Twisted leaf pine and so on.

Widely distributed

Pine trees are widely distributed. Among the pine trees originating in China, Pinus sylvestris var. mongolica, Pinus tabulaeformis, Pinus elliottii and Pinus elliottii are the most cold-resistant, and Pinus koraiensis has the lowest requirements for heat, and Pinus koraiensis, Pinus tabulaeformis, Pinus tabulaeformis, Pinus elliottii, Pinus elliottii, Pinus elliottii and Pinus elliottii are warm temperate and subtropical high-altitude tree species. Pinus massoniana, Pinus yunnanensis, Pinus elliottii and Pinus elliottii are distributed further south, while South Asian pine has the highest requirement for heat. For wetting conditions, five-needle pine is generally higher than two-needle pine, but it also varies from species to species, such as Pinus koraiensis and Pinus armandii, the former requires more wetting conditions than the latter. Pinus koraiensis and Pinus massoniana, both two-needle pine, have higher requirements for wetting than Pinus tabulaeformis and Pinus yunnanensis.

Long life

Pine trees are strong and have a very long life. Experts have found that the life span of pine trees is generally more than 1200 years. In our country, there is a metaphor that "life is longer than Nanshan pine", which also shows that the life span of pine trees is longer. On the cliff at the entrance of the back Hall of Nanshan Temple in Guixian County, Guangxi, stands a 3,000-year-old "immature pine". The fruiting conditions of pine trees are also different. some varieties can produce a little fruit in 5-6 years, and significantly increase in 15-20 years (Pinus massoniana, Pinus tabulaeformis, Pinus yunnanensis, etc.), and some species fruiting very late, such as Korean pine under natural forest conditions. It will not begin to bear fruit until 80-140 years.

Strong adaptability

Pine has strong adaptability to terrestrial environment, can endure low temperature of-60 ℃ or high temperature of 50 ℃, and can grow in bare mineral soil, sandy soil, volcanic ash, calcareous soil, limestone soil and all kinds of soil from podzolic soil to red soil. It is resistant to drought, barren and likes sunlight. Some pines, such as black pine introduced from Japan, have strong salt resistance.

High value

The value of pine is extremely high, and wood can be used for construction, electric poles, sleepers, pillars, bridges, agricultural tools, utensils, furniture, and so on. The cellulose content of all kinds of pine is about 50% 60%, and lignin is 25% 30%. It is one of the important raw materials in the pulp and paper industry, and can also be used as firewood. Because of its majestic and vigorous posture, tall and long-lived trees, it also has important ornamental value. In addition, pine also has high medicinal value.