Sophora hongsenensis is a deciduous tree belonging to Robinia of Butterfly Flower Family. Its flowers, bark and leaves are widely used. It grows rapidly, the trunk is straight and complete, the crown is narrow, and the stipules are small and soft. There were thorns in the first two years and basically fell off after three years. The leaves are dark green, the color is white and the fragrance is pleasant. It is a fast-growing and high-yielding tree species with great market potential.

At present, the afforestation tree species in China are single, and the soil fertility is seriously declining. The construction of mixed forest of Hun Sen and Sophora japonica can greatly improve the soil, and rhizobia, nitrogen fixation and deciduous leaves can enrich the soil. Mixed with elms, poplars and willows, it will grow better. Sophora rubra has developed roots and nodules, which can fix nitrogen and improve soil fertility, so it is better than Salicaceae in barren and drought tolerance, and can grow normally in poor soil. Robinia pseudoacacia has the characteristics of nitrogen fixation, which can improve soil fertility and promote the rapid growth of other mixed forest species, so it is a good mixed forest species. Pinus massoniana is the largest tree species planted in Shaanxi Province. The main forest area of Hanzhong in southern Shaanxi accounts for more than 80%, and Ankang accounts for about 10%, which is one of the main tree species for wood and fuelwood in southern Shaanxi.

People in southern Shaanxi used to grow Pinus massoniana with a hidden hole method (one hoe). After the founding of the People's Republic of China, Shankouzi, Majiazui and other places in Nanzheng County used this method for afforestation. Pinus massoniana has high survival rate and good growth. The "one hoe" afforestation method has many advantages: no land preparation, labor saving, low cost and good effect, and it has been extended to other places. Pinus massoniana is suitable for growing on slopes and hills with thick soil layer, moist and good drainage, and is cold-resistant and barren-resistant.

Seedling raising: first, apply a small amount of base fertilizer to the sandy soil, make the soil into a border, sow pine seeds on the border, and then cover it with fine sand to maintain a certain humidity. After the new seedlings are unearthed, they should be watered frequently, but not soaked. Seedlings can be transplanted when they grow to about one foot and five inches.

Planting is to transplant the cultivated pine seedlings to the hillside or hilly area suitable for growth (where the water can't stop). First, dig a "fish scale pit" with a diameter of more than feet and a depth of more than feet on the hillside (the distance is equal, and the pit is dug all over the hillside like a "fish scale", so it is called a fish scale pit) with a distance of 5 feet. When planting trees, soak the pit with water and mix some mud paste with pots or wooden barrels. The roots of saplings are soaked in the paste and then planted in the pit. After being filled with soil, water "root-fixing water" every day. After that, you can survive by watering it once or twice. This method is an improved method of "one hoe method" Eucommia ulmoides Oliv., also known as silk cotton wood, is unique to China. Li Shizhen, a famous TCM doctor, recorded the medicinal efficacy of Eucommia ulmoides Oliv. As early as in Compendium of Materia Medica, this is a precious tree species. Its bark and leaves have medicinal value, and joinery is the best joinery material. According to modern scientific experiments, it can not only treat many diseases, but also is an industrial insulating and bonding material with high economic value because it contains a lot of "Rabdosia gum". Eucommia ulmoides Oliv. rarely covers a large area. Only Zhouzhi, Xixiang and Ningqiang counties in Shaanxi Province have intensive management and a large number of Eucommia ulmoides Oliv. It was planted by people in southern Shaanxi on all sides (around the house). This kind of tree has dense branches and leaves, and it grows vigorously. It is also a tree species for people to beautify the environment in southern Shaanxi.

Eucommia ulmoides has strong adaptability to climate and soil, but it grows well in the foothills with deep, moist and fertile soil. Seeds: select 20 ~ 30-year-old mother trees with strong development, smooth bark, no pests and diseases and no peeling for seed collection. Before spring sowing, seeds are usually soaked in warm water or cold water to accelerate germination. Sow seedlings in February and March, the height of which is more than two feet, and they can be transplanted in winter or next spring.

Eucommia ulmoides Oliv. is divided into three types: arbor, dwarf forest and cephalopod. When the trees are mature, they can be peeled, cut down and used as medicine. Dwarf forest mainly produces leaves; It can make use of its strong germination ability to cut it dry, fertilize and cultivate the soil in winter to make it germinate and grow again. The branches, leaves and bark of Cephalotaxus fortunei grow rapidly. People often cut off the top of the tree when the trunk grows up, leaving only a trunk of 2.5 meters in the cut part. When the trunk is long and thick and the branches are mature, one branch can be peeled off every year, and then the branches can be replaced, which is called "branch cutting method". Shaanxi is one of the original producing areas of Prunus armeniaca, mainly natural forests. After the founding of the People's Republic of China, many counties in northern Shaanxi and Weibei planted a large number of apricot trees for the purpose of building soil and water conservation forests, forming forest belts. The main product of apricot is almond, which is an important woody oil. As a traditional export material, it is mainly used for medicinal materials, oil extraction, cakes, food and so on. It not only has good economic benefits, but also has the function of soil and water conservation. It is one of the better tree species in the Loess Plateau.

Prunus armeniaca, strong adaptability, drought tolerance and cold tolerance. There are early maturity, medium maturity and late maturity; Separation of separation and adhesion; The difference between sweetness and bitterness.

Planting, generally using direct seeding afforestation, sowing with soil preparation, 3 ~ 5 seeds per hole. There are many kinds of seeds and seedlings in northern Shaanxi. If you sow in spring, people usually hide the seeds in the sand. Seeding, pruning, loosening soil and weeding should be done in the first five years, and reclamation should be done every two or three years, and thinning can be done after ten years.

Almond is not only delicious, but also homophonic with "lucky people", so people often use almond porridge, almond cake, almond soup and other foods at some festive banquets and gifts to get the meaning of "happiness". This custom is very popular throughout southern Shaanxi. Zanthoxylum bungeanum, alias Qin pepper and Feng pepper (namely Fengxian pepper in Shaanxi). It is a rutaceae shrub or a small deciduous tree. Shaanxi province is one of the main producing areas.

As early as 3000 years ago, it was already cultivated. The Book of Songs, Salt and Pepper: "The salt and pepper are real, but its mystery is huge, while the salt and pepper are far away." In Compendium of Materia Medica compiled by Li Shizhen, a famous medical scientist in Ming Dynasty, it is recorded that "Gentiana macrophylla and Zanthoxylum bungeanum were first born in Qin. It can be planted everywhere today and it is the easiest to spread. "

Zanthoxylum bungeanum is the main food seasoning material, as well as spice and oil tree species. It is one of the materials exported by Shaanxi foreign trade. Besides seasoning and oil extraction, its seeds, fruits and peels can be used as medicine, and home-made pesticides can be used to control vegetable pests and aphids. Wood is hard and can be used as a walking stick and umbrella handle. Feng Jiao (Dahongpao) is the most famous pepper in Shaanxi.

In the past, people used to plant pepper in gardens and roadsides, alone, in rows or in dense hedges, with few scattered seeds. After the founding of People's Republic of China (PRC), the Party and the state attached great importance to the development of pepper. Since then, the cultivation of Zanthoxylum bungeanum in Shaanxi has developed greatly. Zanthoxylum bungeanum forest is cultivated in hilly areas of Qin and Ba shallow mountains, and also widely cultivated in Weibei dry plateau. For example, farmers in Hancheng county plant pepper on the banks of Xinjiang (that is, terraces). The well-developed root system of Zanthoxylum bungeanum can not only play the role of soil and water conservation and slope stability, but also can obtain the benefits of diversified management by tending Zanthoxylum bungeanum in combination with agricultural production.

The general cultivation method is "seedling transplanting". Zanthoxylum bungeanum likes to grow in moist, warm and deep soil, and the first half of the vernal equinox is the best time to plant Zanthoxylum bungeanum. If the saplings survive, the two-year-old saplings should be trimmed. If the saplings grow too luxuriantly, they should be pruned after autumn to prevent freezing injury. In the summer dry season, irrigation and loosening soil should be done in time to weed. After the pepper is harvested, it should be pruned to remove the branches of diseases and pests and the branches that are too dense, so as to make it have enough light, and fertilize and cultivate the soil before freezing (severe winter). After flowering in spring, quick-acting fertilizer is also applied to make it bear fruit. In some relatively flat mountainous areas, people planted short crops such as beans and potatoes in the early stage of planting pepper, and after the trees became forests, they operated independently. Tung oil tree is one of the characteristic oil tree species in China, which has a long history of cultivation and utilization. 1200 years ago, tung oil tree was recorded. According to the Records of Shangnan County, tung oil was planted in Shaanxi Province before the Northern Song Dynasty (960 ~ 1 127 (before May of the Northern Song Dynasty and after May of the Southern Song Dynasty)), with a history of more than 800 years. It is planted all over the south of Qinling Mountains (southern Shaanxi), and Ankang is the main producing area of tung oil. According to Shaanxi forest, Shaanxi province accounts for 5 1% of the total area of the country.

The oil extracted from tung oil kernel is the best drying oil. It has the characteristics of quick drying, luster, non-conductivity, heat resistance, acid resistance and alkali resistance. Widely used in industry, it is one of the important foreign trade materials in Shaanxi Province. Historically, it, together with silk and tea, is one of the three major export materials of China, and enjoys a high reputation internationally. According to the introduction of Shaanxi Forest, at present, China's tung oil production accounts for 60% ~ 80% of the world's total output.

Tung trees like to grow in thick, fertile, loose and slightly acidic soil. Sunny, warm and humid, not cold-resistant, afraid of flooding. Therefore, farmers in southern Shaanxi planted tung trees on terraces, with a row of 3-4 meters. Sunny, not afraid of flooding, does not affect the crops in the field. At the same time, when managing crops, it can also care for saplings and let tung trees get enough fertilizer. There is a local folk song: "It's better to be full of trees than mountains" and "homesick for the country, planting more mulberry and paulownia". It shows that planting Sangtong is a good way to get rich, and it is also a traditional custom of the people in southern Shaanxi.