Compound Management Technology of mixed Forest of Taxus mairei and Codonopsis pilosula

Compound Management Technology of mixed Forest of Taxus mairei and Codonopsis pilosula

1 Analysis of the adaptability of compound operation

1.1 main biological characteristics

Magnolia officinalis is a deciduous tree, distributed in the altitude range of 500 to 1 500 m, and likes cool, humid and well-lit environment. It grows well under the conditions of fertile, multi-humus, good ventilation and good drainage, and the soil pH in the distribution area is slightly acidic to neutral. Generally, the leaves differentiate in the middle of April and fall gradually after September. The crown width of Magnolia officinalis is 2.8 m × 3 m and the tree height is 8.9 m after 12 years of mixing with coniferous species. The results showed that although Magnolia officinalis was a shallow root tree species, the root system of Magnolia officinalis was mainly concentrated below 40 cm soil depth after mixing with coniferous species. Magnolia officinalis generally needs to grow for more than 15 years before it can be peeled for medicinal use. Taxus chinensis var. mairei is an evergreen tree, distributed in the altitude range of 500m to 3500m, and likes dark and humid environment. Excessive light is easy to cause poor growth. It grows better on humid yellow brown soil and yellow soil, and the soil pH in its distribution area is weakly acidic. The growth rate of Taxus mairei is slow, and the height of 12-year-old Taxus chinensis var. mairei is only 4-6 m. Codonopsis pilosula is a perennial herbaceous vine distributed in the alpine area of 900-3000 m above sea level, which likes moist and cool environment and seedlings like shade. It grows well in the soil with rich organic matter, good ventilation, good drainage, neutral and weak acid. The stem is twining, about 1m long, and the big seedling needs to set up a shed frame for its climbing and daylighting.

1.2 adaptability analysis

Magnolia officinalis, Taxus chinensis var. mairei and Codonopsis pilosula have overlap space in altitude, climate and other environmental conditions. Magnolia officinalis likes the sun and the leaf area increases rapidly, which can provide shade for Taxus chinensis var. mairei. After mixing Magnolia officinalis and Taxus mairei, the root system of Magnolia officinalis which grows more strongly to the soil is distributed to the deep soil because of the limited competition space on the soil surface. Taxus chinensis var. mairei roots are concentrated in the surface layer, which makes effective use of soil fertility space. Codonopsis pilosula grows fast and can cover the surface in a short time and reduce soil erosion and soil nutrient leaching. In the summer with the strongest light every year, the increase of leaf area of Magnolia officinalis reduces the window and increases the canopy density of woodland, which makes the temperature and light under the forest more suitable for the growth of Codonopsis pilosula. Codonopsis pilosula annual fertilization, weeding management, mature mining and other management activities can improve the soil condition of woodland, take care of ploughing, and promote forest growth.

2 selection of afforestation site

Select yellow brown soil or brown soil with sufficient light, deep soil layer, high humidity, good drainage and ventilation, rich organic matter and soil pH 6.5-7.0 for afforestation in the range of 900-1 500 m above sea level.

3. Land preparation and afforestation

3.1 Land preparation

Afforestation before budding from mid-February to early March every year. It should be planted in cloudy or cloudy days and when the soil is moist. The way to clean up the woodland is comprehensive cleaning. Before soil preparation, remove the cutting leftovers or weeds and shrubs on the afforestation land, use full land reclamation, depth 30cm, and apply farm manure as base fertilizer according to 1500kg/666.7m2.

3.2 afforestation

Magnolia officinalis seedling height ≥ 50 cm, ground diameter ≥ 0.7 cm;, Taxus mairei seedling height ≥ 70 cm, ground diameter ≥ 0.8 cm. The distance between rows is 4 m × 2 m. The mixing mode was row-like mixing, and the mixing ratio was 1 ∶ 1. Seedlings are planted with "three buries, two steps and one lift". The injured roots and overlong roots should be trimmed to ensure that the roots are extended.

3.3 Codonopsis pilosula planting

From October to November every year, the whole ground was trenched according to the row spacing of 30 cm and the depth of 15 cm, and then the ginseng seedlings were placed in the trench according to the plant spacing of 10 cm, and covered with soil for 5 cm. Ginseng seedlings were used for 40-50 kg per 666.7 m2.

4Post-afforestation management

4.1 forestland tending

After afforestation, compound fertilizer was applied once a year in May, and Codonopsis pilosula could apply human and animal manure once before erection, three times of weeding in summer, one time of weeding in winter, and one time of rotten compost or barnyard manure when the seedlings were cultivated, the dosage was 1000 kg/666.7 m ~ 2.

4.2 pruning and tillering

During the forest cultivation period, the branches below 1.3 m of the trunk and the sprouting of the stem base were removed every year.

4.3 set up a frame

The seedlings of Codonopsis pilosula were put on the shelf after the height of 20 cm, and one was inserted with thin bamboo strips and miscellaneous wood every 2 to 3 m, or built into a herringbone support to ensure ventilation. Attention should be paid to avoid Codonopsis pilosula branches clinging to Magnolia officinalis and Taxus chinensis var. mairei young trees in the young forest period, so as not to affect their growth. After the DBH of Magnolia officinalis and Taxus chinensis var. mairei is 5 cm, they can climb freely.

4.4 Disease and pest control

The main diseases of Magnolia officinalis are root rot, leaf blight and coal pollution, and the main insect pests are forked diagonal net moth, Dendrolimus punctatus, Magnolia sinensis aphid, etc.; the main diseases of Taxus mairei are stem rot, white silk disease, leaf mites and aphids; Codonopsis pilosula main diseases are root rot and rust, and the main pests are grubs, golden needles and other underground pests. Reasonable pruning, timely removal of diseased branches, diseased plants and residual leaves caused by diseases and insect pests, reduction of disease and insect sources and strengthening tending management should be carried out during forest management so as to promote stand growth and early canopy closure. Protect and utilize natural enemies to control pests with beneficial organisms. Use black light to trap and kill pests, artificially remove the leaves eaten by injured insects, and centrally destroy the removed leaves. If both physical control and biological control can not control diseases and insect pests, it is necessary to use chemicals with good effect, low toxicity and side residue and little influence on natural enemies, pay attention to the collocation and alternation of drugs, and prevent the resistance of diseases and insect pests to offset the control effect. pesticide spraying is prohibited within 30 days before harvest.

With careful management, Magnolia officinalis can be harvested after growing for 15 years and Codonopsis pilosula for 3 years, and branches and leaves of Taxus mairei can be collected and used after 3 years of planting.

5 benefit analysis

To carry out forest compound management and tap the planting potential under the forest is the trend of the development of forestry industry in the future. Planting Codonopsis pilosula under the mixed forest of Magnolia chinensis and Taxus mairei is a new model for the development of forest medicinal materials. Compared with the pure forest, the compound management model has the following advantages: first, it increases the growth rate of the biomass of the medicinal parts of Magnolia officinalis, and promotes its thickening and height growth. The DBH of mixed Magnolia officinalis is 3.6% higher than that of pure forest, and the tree height is 23.6% higher than that of pure forest. The second is to reduce the forest land tending cost and increase economic income by planting Codonopsis pilosula, and there is no need to invest special funds for cultivation. After Codonopsis pilosula matures, the output of Codonopsis pilosula is 250 kg/666.7 m2, the unit area can be increased by 2000 yuan, and the third is to increase biodiversity through compound management, which can maintain ecological balance and effectively prevent the large-scale occurrence of diseases and insect pests.