Germplasm mbth: Pinus densiflora
Family name (China/Latin America): Pinaceae/Pinaceae.
Genus name (Chinese/Latin): Pinus.
Name (Chinese): Pinus densiflora
Name (Latin): Pinus densiflora.
Germplasm origin: Asia-Japan
The bark on the upper part of the trunk of Pinus densiflora is reddish brown with flakes falling off. Branchlets pale yellow or reddish yellow, slightly covered with white leaves in a bunch of 2 needles. The cones are dark brown or light brown when they are mature; Seed scales are thin and flat, usually with thorns. Distributed in eastern Heilongjiang, Changbai Mountain in Jilin, central Liaodong to Liaodong Peninsula and Jiaodong Peninsula in Shandong. Japan, Korea and the Soviet Union are also distributed.
Biological characteristics are shown in the following aspects.
Requirements for climatic conditions due to differences in geographical distribution of origin. Pinus sylvestris var. mongolica, Pinus yunnanensis and Pinus elliottii, which are native to China, are the most hardy and have the lowest requirements for heat. Korean pine doesn't require much heat either. Pinus densiflora, Pinus tabulaeformis, Pinus bungeana, Pinus armandii, Pinus taiwanensis, Pinus taiwanensis and Pinus Bashan are tree species in warm temperate and subtropical high altitude areas, which need moderate heat. Pinus massoniana, Pinus yunnanensis, Qiao Song and Pinus Simao. Langbianensis is located further south and needs more heat. South Asian pine is a tropical pine with the highest requirement for heat. The requirement of five-needle pine on wet conditions is generally higher than that of two-needle pine, but it also varies from species to species. For example, Pinus koraiensis and Pinus armandii, both five-needle pine, have higher requirements for wet conditions than the latter; Pinus densiflora and Pinus massoniana are both two-needled pines, which require higher water content than Pinus tabulaeformis and Pinus yunnanensis. This is related to the substitution phenomenon with longitude in geographical distribution.
Requirements for soil Pine trees can grow in different soils. Because of the low ash content of needles, they can tolerate poor soil, but when planted in loose and fertile soil, their productivity is high. Pine trees in humid areas are mostly suitable for acidic soil. Some pine trees, such as Pinus bungeana and Pinus tabulaeformis, can adapt to the soil with high calcium content and high pH value, and there are mycorrhizal fungi in the root system of pine trees. The hyphae of ectomycorrhiza mainly form a sheath around the short lateral roots, which is beneficial to the absorption of water and nutrients by the roots. Therefore, inducing mycorrhizal development is very important for the success or failure of some pine trees. Most pine trees can't grow on saline-alkali land, so they can't grow near the seashore. But some pine trees, such as black pine introduced into China from Japan, have strong salt tolerance.
Shade tolerance and tree species replacement Most pine trees, especially apricot pine, are light-loving trees with weak shade tolerance. Its appearance is sparse crown and natural pruning height; Physiologically, the compensation point is low; Most of them are pioneer trees with forest characteristics. When virgin forests are destroyed or burned, they can easily develop and occupy bare space. For example, the evergreen broad-leaved forest in the south of China is easily replaced by Pinus massoniana or Pinus yunnanensis. However, these pine forests are not stable. When they form an appropriate forest environment, they create conditions for the occurrence and development of some basic forest tree species that are relatively shade-tolerant, and are eventually replaced by other tree species, which have an opposite position in tree species replacement. Korean pine broad-leaved forest is a zonal forest in temperate humid areas of China. Korean pine is a basic forest tree species with strong shade tolerance. After the original Korean pine forest was destroyed or burned, broad-leaved trees such as Populus davidiana mainly appeared as pioneer trees, followed by Korean pine, and finally recovered its dominant position because of its shade tolerance and longevity. In addition to the substitution of Korean pine, Populus davidiana and Betula platyphylla, there is also the substitution of Mongolian oak () and Korean pine.
Drought-tolerant pine trees have xerophytic structure: narrow leaves, developed cuticle, small surface-to-volume ratio, depressed stomata and fully developed thick-walled tissues. Physiologically, they are more tolerant of water shortage than mesophyll trees. Ecology, pine trees are xerophytes. Most pine trees distributed in different climatic zones can grow in rocky and shallow arid habitats. Generally speaking, the drought resistance of two-needle pine is stronger than that of five-needle pine. Too much is bad for the growth of pine trees.
Some flowering and fruiting pines bear fruit earlier, and a small amount can bear fruit in 5 ~ 6 years, and 15 ~ 20 years increases significantly (Pinus massoniana, Pinus tabulaeformis, Pinus yunnanensis, etc. ); Some tree species bear fruit very late, such as Pinus koraiensis, which began to bear fruit in 80 ~ 140 years under natural forest conditions (but it began to bear fruit in 15 ~ 20 years under artificial forest conditions). Most pine trees bear fruit at regular intervals and are harvested every 2-3 years or longer. The male cone of pine is located at the base of the new shoot, and the female cone is more common at the axial end of the main branch. It takes a long time for cones to mature. The male and female cones of a few tropical pine trees appear from the buds in late winter, while the cones of most pine trees appear from the buds in early spring, late spring or early summer. Male cones are clustered, green or yellow to red before maturity, light brown or brown when shedding, and fall off soon after maturity. The female cone appears immediately after the male cone, and the male cone is green or reddish purple. When pollinating, the female cones are almost upright. After pollination, the scales closed and cones began to develop slowly. Fertilization occurs in spring or early summer/0/3 months after pollination, and then cones begin to grow rapidly, generally maturing in late summer and early autumn of the following year, and the color of cones gradually changes from green and purple to yellow, light brown or dark brown. When most pinecones mature, the scales open quickly and the seeds fall off quickly (Pinus massoniana, Pinus tabulaeformis, etc. ); Several pine trees have their scales open and their seeds fall off for months. Some pine trees, some or all cones are closed in a year, or irregularly open on the trees. Korean pine cones are big and heavy, and are easily blown off by the wind before and after maturity.
The growth process of pine trees varies with tree species. Pinus tabulaeformis, Pinus massoniana and Pinus yunnanensis grew faster in the early stage, but reached quantitative maturity later; Before 5 years old, the growth of tree height and ground diameter is slow, and the peak growth period is 5 ~ 20 years. Natural Korean pine DBH grew slowly 50 years ago, and flourished in 50 ~ 100 years. After that, it maintained a high speed, and it decreased significantly after 200 years. The growth period of Gao Wangsheng is about 100 year; The age of quantitative maturity is about 300 years. In the artificial forest, the early growth of Korean pine is obviously accelerated. Generally, DBH and tree height only grow slowly before 10, and reach the peak after 10 ~ 30 years of growth. Like other tropical pine trees, the growth process of South Asian pine has a tufted stage. From germination to 4-year-old, the stem height of seedlings grows slowly, while the coarse growth grows quickly. For example, needles are as dense as grass, and the terminal buds are hidden in leaves. After the grass sample stage, the height growth suddenly accelerates, and it can grow by 80 ~ 130 cm per year. Pinus yunnanensis also has a shrubby stage when it is young.
Pine trees with forest variability are cross-pollinated plants, and there are extensive variations among individuals, stands and provenances (producing areas). The types of pine trees can be distinguished according to individual differences. For example, Pinus tabulaeformis in Zunhua, Hebei, China, is traditionally divided into three types: Korean pine (Pinus tabulaeformis), which is heavier in material and color and contains more resin; American pine (pine chaff), white in material and less in resin; Thousand bark pine (coarse bark pine), heavy material, yellow. In the south, Pinus massoniana is divided into Pinus tabulaeformis (thin skin) and Pinus tabulaeformis (thick skin). Contemporary studies on individual variation of pine trees still divide pine trees into different types (Pinus tabulaeformis, Pinus massoniana and Pinus sylvestris var. mongolica). Pinus sylvestris var. mongolica, Korean pine, etc. ) according to the thickness and color of bark. In addition to the characteristics of bark, the width and density of crown are often used as the basis for classification (Pinus massoniana and Pinus tabulaeformis). Extensive provenance tests show that pine trees generally have geographical variation, so different ecotypes can be divided within the same species. The study of geographical variation of pine is the basis of seed zoning and seed selection.
The afforestation area of pine trees ranks first among conifers in the world. As early as Qin Shihuang's time, China planted a pine tree every three feet on the post roads in the Yellow River and Yangtze River basins. In the Song Dynasty, Su Shi summarized the technical points of pine afforestation in his works such as Dongpo Miscellanies. Modern pine afforestation mainly includes the following links.
Most pinecones change from green to yellowish brown, which is a sign of maturity (Pinus massoniana, Pinus tabulaeformis, Pinus koraiensis, Pinus armandii, Pinus bungeana). For tree species (such as Pinus tabulaeformis) whose seeds are easy to fall off quickly after cone ripening, seeds should be collected immediately after cone ripening. The cones of some tree species do not crack for a long time after maturity (such as Pinus sylvestris var. mongolica. Mongolian almond can be kept for 6 ~ 7 months), and the seed collection period can be extended. In addition to manual seed collection, seeds can also be collected by mechanical means, such as vibrating seed collector. When the cones are threshed after harvest, they can be exposed to the sun (such as Pinus tabulaeformis) or heated indoors (such as Pinus sylvestris var. mongolica). Mongolian almond, stored at room temperature 45℃).
Before sowing, seeds are often germinated, which can be soaked or layered. For seeds without dormancy (such as Pinus tabulaeformis, Pinus massoniana, Pinus yunnanensis and Pinus sylvestris var. mongolica). Mongolia and so on. ), the seed soaking method is adopted, that is, the seeds are soaked in cold water or warm water for 65,438+0 days before sowing, then placed in a warm place and washed once a day with cold water or warm water until most of the seed coats crack. The seed coat of Pinus armandii is thick and can be soaked in cold water or warm water for 3 ~ 7 days. Seeds of Pinus bungeana, Pinus koraiensis and Pinus yunnanensis. It is dormant, so it needs long-term sand storage or stratification treatment to create low temperature, humidity and ventilation conditions for seeds.
Seedlings for afforestation of pine trees can be divided into bare-root seedlings and container seedlings. Bare root seedlings are the most widely used. Generally, bare-rooted seedlings are cultivated in high beds, and the width of the bed surface is not more than 1 m, and the length is not limited. Most of them are drilled. The thickness of the back covering soil is generally 2 ~ 3 times of the seed diameter. In order to keep the ground moist and promote the germination and emergence of seeds, grass and sawdust. Can be spread on the ground, and then they will be removed one by one with the emergence of seedlings; It can also be covered with plastic film. The sowing amount per unit area depends on tree species, seed size and germination rate. 1 year-old pine seedlings are vulnerable to cold damage in winter, and some areas need to be covered with soil or planted with grass to prevent cold. In the process of seedling growth, it is necessary to weed frequently. In order to adjust the proportion of rhizome, promote the growth of root system and benefit the survival of afforestation, transplanting or root cutting can be carried out. Transplants are usually carried out in the spring of the following year. Mycorrhizal soil can be used for seedling raising, which is beneficial to seedling growth and control. Various containers can be used. Seedling raising with nutrient brick of Pinus massoniana in South China is a form of combining seedling raising substrate with container. The nutritional brick is made by mixing yellow mud, burnt soil and calcium superphosphate, adding water, kneading into paste, making into a bed, slightly drying and cutting into pieces. Each piece is 6 cm long, 6 cm wide and about 12 ~ 13 cm high, and 1 ~ 3 seeds are sprinkled on it. Usually sow 1 1, and sow seedlings in February of the following year for afforestation in spring. Because the seedling period is about 100 days, it is called winter sowing seedlings 100 days.
Planting and Afforestation Planting and afforestation techniques vary according to the types of seedlings. The root system of container seedlings is not easy to be damaged during planting, so the survival rate is high. Afforestation technology is also relatively simple. During the growth of bare-rooted seedlings, the tiny active roots are mostly damaged, and their survival depends on the regeneration ability of roots and environmental conditions, as well as the quality, age, planting season and planting method of seedlings. Because of the developed root system and large ratio of root to rhizome, the survival rate is generally higher than that of native seedlings. The seedling age of afforestation mainly depends on the tree species. Generally speaking, Korean pine is suitable for 2-3 years, but it is suitable for 3-4 years in lush cutting areas. Pinus tabulaeformis in North China is planted with 1.5-year-old seedlings in rainy season and 2-year-old seedlings or transplanted seedlings in spring. Pinus massoniana seedlings are sown 1 year, or even sown in autumn 100 days, and produced in the following spring. Generally, early spring is a suitable afforestation season, but rainy July and August can be chosen in North China and Northwest China where spring drought is severe. There are two planting methods: hole planting and seam planting. It is practical to keep the roots moist and stretch them when planting. For injured and too long lateral roots, they can be trimmed properly before planting. Afforestation in arid areas can take various measures to reduce surface evaporation. Generally, 1 plant is planted at each planting point, but some plants are clustered, that is, 2 ~ 4 plants are planted at each planting point. Cluster planting is beneficial to improve the survival rate and promote the growth of young trees. The planting density of pine trees should be 4444 trees per hectare (plant spacing 1.5× 1.5m), or 3333 trees per hectare (plant spacing 1.5×2.0m), or even 2500 trees (plant spacing 2× 2m).
There are two ways of direct seeding afforestation: artificial direct seeding and aerial seeding. When sowing artificially, hole sowing is often used. Sow 3 ~ 5 large seeds such as Pinus armandii and Pinus koraiensis, and 20 small seeds such as Pinus tabulaeformis, Pinus massoniana and Pinus yunnanensis 10 ~ 20 in each hole, and cover the soil after sowing. Sometimes sewing is also used, that is, sewing with a sickle. After sowing the right amount of seeds, the seams will be practical, and weeds and shrubs will not need to be removed. The purpose is to prevent the seeds from being found by birds and animals, and the seedlings can be blocked by vegetation. Sowing is a relatively extensive method. Seeds are scattered on the ground, and no soil preparation or ditching is carried out. It is the enemy of pine direct seeding, especially the big seeds of Pinus koraiensis and Pinus armandii are more vulnerable, which can be controlled by chemical agents such as zinc phosphide. The seeds treated by accelerating germination have quick emergence after sowing, little smell of seeds and light rodent damage. Many areas also have the experience of mixed crops. Pinus massoniana, Pinus yunnanensis and Pinus tabulaeformis are suitable for aerial seeding in China. Good seed treatment (such as accelerating germination and mixing drugs, etc.). ), choosing sowing date, properly removing vegetation and excessive dead cover are the main ways to improve the effect of aerial seeding of pine trees (see).
Pure pine forest is prone to diseases, pests and fires, and its productivity is also low, so whether planting or direct seeding is used for afforestation, attention should be paid to construction. The mixing type can only be determined by long-term experiments. In Northeast China, common tree species naturally mixed with Korean pine are Tilia amurensis, Betula platyphylla, Picea koraiensis, and Abies odorata.
The most common and serious occurrence of diseases and insect pests in seedling stage is damping-off, which is manifested as seed rot before seed collection, top rot, damping-off, damping-off after seed collection and other symptoms. Leaf blight of Pinus massoniana seedlings is sometimes very serious. Common leaf diseases include pine needle rust, speckle disease and Pinus massoniana wilt. The latter two kinds mostly occur in stands with poor site conditions, poor soil and poor growth. The cadre diseases include blister rust and five-needle pine blister rust, which are very important in the world and have destroyed a large number of five-needle pine forests in Europe and North America. Young Korean pine forests in northeast China have also been seriously affected. Pinus massoniana and Pinus taiwanensis have pine rust in the stands with strong nest wind, high humidity and many oak trees; White rot of pine roots is also quite common.
It is the main leaf-eating pest of pine trees and often causes great losses. Tricholoma matsutake mainly harms Pinus massoniana and Pinus tabulaeformis, and often occurs with Dendrolimus punctatus in Guangxi, which can be rampant. Pine needle moth larvae, etc. It's also seriously damaged. Neoptera caused disasters intermittently in different distribution areas. Red spot borer is almost all over the country, and it is the most important pest to drill the main branches. Because of the replacement of the main branches, the side branches are clustered or the main branches are bent. Pine-tip moth can also make the main tip suffer and wither. Trypanosoma can damage Trypanosoma (see). The bark beetle is a big pest that damages branches and leaves, which can kill pine trees in pieces, but generally does not harm healthy Pinus armandii, and the bark beetle can run rampant. Pine bark beetles, deciduous pine bark beetles and spruce bark beetles can also damage healthy trees. The geometrid is a destructive pest, which destroys branches by piercing and sucking. Control should be based on the principle of reasonable mixing and good tending management, and chemical control can be supplemented if necessary.
Wood and other products are generally divided into softwood pine and hardwood pine according to structural characteristics and wood properties. Cork pine (that is, subgenus of single vascular bundle) is light and soft, uniform in texture, low in strength, easy to process, with gradual change from early wood to late wood and few wing cracks. Hardwood pine (that is, subgenus of double vascular bundles) is relatively hard, uneven in texture, high in strength, difficult to process, fast in transformation from early wood to late wood, and high in rosin content. However, Hainan five-needled pine and South China five-needled pine belonging to cork pine are close to hardwood pine in strength and bulk density. Pine can be used in buildings, telephone poles, sleepers, columns, bridges, farm tools, appliances, furniture and other purposes. The cellulose content of various pine trees is about 50 ~ 60%, and the lignin content is 25 ~ 30%, which is one of the important raw materials for pulp and paper industry. Pine trees can also be used as fuelwood.
Turpentine can be extracted by cutting from the trunk of pine trees. Pine nuts are rich in protein and oil, and the oil content is above 30%. Among them, there are 20 species with edible value, such as Korean pine, slash pine and Huashan pine, all of which are produced in China. The seeds of Korean pine can also be used as medicine, and the medicine name is "sea pine seed", which is a nourishing tonic. The bark and seed coat of pine trees are rich in tannin and can be extracted by soaking. After the bark is crushed, it can be mixed with other raw materials and pressed into hard fiberboard. In addition, pine needle volatile oil can be extracted from pine needles. Needles are rich in carotene, vitamins, fat, protein, calcium, phosphorus and other mineral elements, which can be processed into feed and livestock additives. Incomplete combustion of pine branches and roots in kiln can produce pine smoke (see), which can be used to make ink, ink and black paint. Pine branches and roots are also raw materials for cultivating valuable medicinal material Poria cocos.
Ornamental value Pine trees not only have economic uses, but also have important ornamental value because of their majestic posture and long life. It is an important part of many scenic spots in China. For example, Qian Shan in Liaoning, Mount Tai in Shandong and Lushan in Jiangxi are all famous for their pine scenery. Especially in Huangshan, Anhui, pine, cloud and stone are also called "three wonders", led by pine. Many Gu Song in various places are closely related to China's long history and culture. For example, there is an 800-year-old Gu Song in Beijing Beihai and Yuanmingyuan, which is said to have been named "Yin Hou" by Qing Qianlong. The legend of Mount Tai's "Five Buddha Pines" is that Qin Shihuang went up the mountain to shelter from the rain and was given an official title. People in China regard pine trees as a symbol of firmness, chastity and longevity. Song, Song and Song are known as "three friends of the old and the cold", which means the indomitable spirit of defying adversity and overcoming difficulties.
philology
Comparative Morphology: Morphological Structure and Development of Pines, Science Press, Beijing, 1979.