Cinnamomum, belonging to Lauraceae, is 20 meters tall, with a diameter of 50 centimeters and a smooth bark. Branchlets, buds, petioles, leaves, flowers, peduncle, peduncle all densely covered with pale yellow, silky pubescence. Leaves subopposite or alternate, leathery, lanceolate to elliptic, 4-11 cm long, 2-4 cm wide, tapering to caudal tip, light green above, yellowish green below, three-veined at 1-4 mm from base, lateral veins obliquely extending to near apex, slightly depressed above, protruding below. Inflorescence 6~9 cm long; flowers yellowish, 4 mm long, villous on both sides of perianth lobes. Ellipsoid, 7 mm long, fruit cupped, cupped, margin entire. Cinnamomum Cassia is produced in the south of the Yangtze River, West to Sichuan, Yunnan, Tibet; born at an altitude of 1000 meters or below 2500 meters (southwest). Southeast Asia also has many awards. Shade-tolerant, warm and humid, requiring fertile soil, in the Hengshan valley, foothills and Castanopsis mollissima, Shuiqinggang, Cortex Zingiber and other mixed. The material is slightly different from Cinnamomum cassia. Cinnamomum Cassia is not only an evergreen tree species, but also an economic tree species, suitable for planting a wide range of economic benefits. Cinnamomum cassia bark can be extracted fragrant oil, mainly containing cinnamaldehyde, used in toothpaste and cosmetics; branches and leaves can be extracted fragrant oil called cinnamon leaf oil, used in the instrument industry, has germicidal and antiseptic effect, bark also used as medicinal and edible "cinnamon". It is one of the ideal afforestation tree species for the project of returning farmland to forestry because only the branches and leaves will not cause new soil erosion. Some of its planting techniques are introduced below for reference.
1 natural conditions for planting Cinnamomum cassia
1.1 soil conditions
Cinnamomum cassia L. is a yellow clay soil developed from limestone and belongs to karst landform. Soil pH value is above 5.8, organic matter 6.54%, total nitrogen 0.32%, total phosphorus 0.046%, total potassium 3% under the conditions of good growth. If the soil is too barren, it will cause plant dwarf, slow growth, thin leaves, affecting the oil content of branches and leaves.
1.2 climatic conditions
In the humid monsoon climate region of the middle subtropical zone, the average annual temperature is 16.7-18.1, the frost-free period is 329-340 days, the accumulated temperature is 5178-5602, the sunshine time is 1042.4-1152.4 hours, and the rainfall is 1152.4-1042.4 mm. The planting area requires high heat, adequate rainfall and long sunshine.
2 seedling raising techniques
2.1 seed seedling raising
Seed breeding has the advantages of high survival rate, no damage to plants, convenient packaging and transportation, less need for quantity, easy field management, and has been widely used in production.
2.1.1 The seeds were harvested and put aside for 1-2 days. The peel was rubbed off. The gum on the surface of the seeds was removed by rubbing repeatedly with warm water. Then the seeds were dried in the shade and stored in sand about 15% water loss. The seeds were disinfected with 0.5% potassium permanganate in 45 C warm water, soaked for 1 h, leached out the liquid, washed and dried, mixed with tung oil and grass ash, and planted in reserve.
2．1．2 圃地準備育苗地應選擇比較平坦、土質深厚、肥沃、石礫少的微酸性土壤。苗床須深耕平整，施足底肥，畦寬1，條播行距10~15cm。播種密度為4萬 ~6萬粒/667㎡，覆土厚度為種子直徑的2倍。
2.1.2 The nursery land should choose the slightly acidic soil which is flat, deep, fertile and less gravel. The seedbed must be deep ploughed and flat, with enough base fertilizer, 1 wide and 10~15cm spacing. The planting density is 40 thousand ~6, ten thousand /667, and the thickness of covering soil is 2 times of seed diameter.
2.1.3 seeding time can be sowed in spring and autumn in two seasons, but autumn sowing is better.
2.1.4 field management should be as dry as possible to avoid the drying of topsoil. By rational irrigation, the bed surface can be kept wet, seedlings can be prevented from losing water, and the surface temperature can be adjusted to prevent sunburn. Seeding seedlings generally require more irrigation times and less irrigation. Sowing and nursery seedlings in the seedlings before the soil to weed and loosen, generally in irrigation or rain can be operated. In addition to general management such as fertilization and weeding, the autumn seedling should be interplanted with iron pan to reduce evaporation of water and increase surface temperature. Spring sowing can be intercropped with maize and other high-stalk crops, which can play a shading role.
2.2 cutting seedlings
The survival rate of cuttage seedlings is relatively low, generally around 26%. Cutting time is good in 2 and March. The middle and lower 2-3-year-old branches of robust, short internodes and insect-free plants were selected as cuttings, and the length was 15-20 cm. Cutting distance 16~17cm, spacing 10cm, cutting density can reach 40 thousand plants /667. Summer shading is the key to increase cuttage survival rate. Cutting seedlings need more water for rooting and sprouting, especially in the stage when the leaves are just beginning to spread and the roots are not yet fully formed (i.e. "false living"), the transpiration of the leaves is large, the supply of soil water is small, and the water shortage will cause death.
2.3 tillering seedling raising
The roots of Cinnamomum Cassia have strong tillering ability. Generally, tillering propagation is carried out in late autumn and early spring when the temperature is not high. Due to the truncation of roots during planting, the imbalance of water supply in seedlings must be strengthened to solve the problem. 3~4 should be continuously irrigated after the ramet transplant, and the irrigation volume should be larger and the interval time should not be longer.