Detailed Explanation of Key Techniques for High-Yield Cultivation of Bambusa multiplex

Bambusa multiplex shoots have excellent quality, being fragrant and crisp, and are rich in various amino acids needed by the human body, making them a natural green food. The bamboo culm wall is thick and elastic, making it a good material for scaffolding, papermaking, furniture making, and processing other items, with high comprehensive utilization benefits. It is an excellent scattered bamboo species dual-purpose for both shoots and timber. However, existing Bambusa multiplex forests have long been in a wild and unmanaged state, with only harvesting and no cultivation, only collecting and no management, resulting in unreasonable bamboo forest structure, low yield, and low economic benefits. Therefore, its high-yield cultivation techniques are briefly introduced for reference.

1 Forest Land Management

1.1 Timely Weeding, Shallow Turning, and Adding Guest Soil

Weeding is carried out 3 times a year, respectively in February to March, May to June, and August to September. Shallow turning is scheduled in early spring each year, with shallow cultivation being appropriate, at a depth of about 10cm, and not too deep. Combined with shallow turning, weeds, shrubs, tender branches and leaves, dead branches, or fallen leaves in the forest land are buried into the soil, while tree stumps and stones are cleared, and old and dead rhizomes over 7 years of age are dug out. Pits left from cutting bamboo and digging shoots should be filled with soil in a timely manner, achieving digging, cutting, and filling simultaneously to ensure normal growth of bamboo rhizomes and root systems. Where conditions permit, from November to December each year, add 3-5cm thick guest soil to the forest land to increase soil fertility and promote bamboo growth.

1.2 Rational Fertilization

Fertilization is best carried out during spring shoot digging via shoot-hole fertilization, or after new bamboo has grown and during the shoot bud differentiation period, using organic fertilizer or chemical fertilizer applied in trenches. When applying barnyard manure, cake fertilizer, human excrement and urine, plant straw, and household waste, organic fertilizers must be thoroughly decomposed before application, at a rate of 500kg per mu (667 square meters, same below). For chemical fertilizers, NPK ternary compound fertilizer can be used at 50kg per mu, applied in combination with watering or after rain. Where conditions permit, fertilizer can be applied once each during the rhizome growth period, shoot bud differentiation period, early shoot gestation period, and shoot growth period, ensuring sufficient nutrients for bamboo shoot and new rhizome growth as well as rhizome bud and shoot bud differentiation, laying a good foundation for sustained high and stable yield of the bamboo forest.

1.3 Intercropping in the Forest

The special ecological environment of Bambusa multiplex groves can be utilized for intercropping shade-tolerant crops such as beans or forage @#@230@#@ groups within the forest. Through intercropping, soil and water can be conserved, tending costs reduced, and soil structure improved and soil fertility increased through loosening the soil, while also generating certain income.

2 Bamboo Forest Management

2.1 Appropriately Increasing Bamboo Forest Management Density

For managing a dual-purpose shoot and timber forest, the optimal density for high-yield Bambusa multiplex can be controlled at 7000-9000 plants per hectare, but existing Bambusa multiplex forests almost all have low density, so in production, bamboo forest density should be effectively increased by annually increasing the number of retained shoots and controlling the harvest amount. To increase density, artificial replanting can also be carried out. That is, in forest gaps near dense bamboo clumps, select 1-3 year old mother bamboos with a ground diameter of 1-2cm, low branch height, vigorous growth, and no pests or diseases, and transplant them with rhizomes. The planting hole specifications are 80×40×40cm. To prevent excessive water evaporation and improve survival rate, mother bamboos should retain 3-4 branch whorls, with the rest cut off.

2.2 Moderate Top Pruning

Moderate top pruning of bamboo forests is beneficial for ventilation and light penetration, stimulates balanced redistribution of bamboo leaves, helps branch and leaf growth and rhizome expansion, and can also improve disaster resistance and enhance the bamboo forest's ability to withstand harsh environments. Timing of top pruning: First, when bamboo has grown to a certain height but has not yet unfurled leaves, using the method of cutting or shaking the top, at which time the shoot tips after top pruning can still be eaten; Second, after bamboo has unfurled leaves, a sharp knife can be used to cut off the bamboo top, which is the optimal time for top pruning; Third, 2-3 months after bamboo height growth has stopped, use a knife to cut off the bamboo top. Top pruning should retain about 15 levels of branch whorls, with intensity controlled at about 15%.

2.3 Rational Harvesting to Form a Reasonable Bamboo Age and Forest Structure

In the early stage of bamboo forest improvement, harvesting should be strictly controlled. Bamboo below age class IV should not be cut, and old bamboo above age class V should also be retained if growing in open areas of the forest land, in order to retain more mother bamboos for shoot production and rapidly increase stand density. After reaching reasonable density, combine with moderate retention of new bamboo. In winter, cut bamboo above age class V and about 2/3 of age class IV bamboo, so that the bamboo forest forms a reasonable and stable bamboo age structure with a ratio of age class I, II, III, and above IV bamboo of 3:3:2:2. For Bambusa multiplex forests in the initial improvement stage, it is best to retain about 225 broadleaf trees per hectare or retain tree species with nitrogen-fixing ability that can promote Bambusa multiplex growth.

3 Shoot Period Management

3.1 Scientific Shoot Digging

Shoot digging should consider the tools, timing, intensity, and method. A specialized shoot spear should be used as the digging tool to ensure the excavated bamboo shoots are complete and undamaged without harming the rhizome. The best digging time is when the shoot tip has grown to about 10cm above the ground. If too small, yield is affected; if too large, the base of the bamboo shoot ages, affecting shoot quality, and also consumes rhizome nutrients, affecting later emerging shoot growth. Digging intensity should ensure sufficient mother bamboo shoots are retained, with all remaining shoots harvested. The digging method should adopt a spot-digging approach, digging one plant at a time.

3.2 Rational Shoot Retention for Bamboo Cultivation

Shoot retention for bamboo cultivation should follow the principles of "retain distant ones and dig near ones, retain strong ones and dig weak ones, retain sparse ones and dig dense ones," thinning out some shoots close to mother bamboos so that bamboo plants in the forest gradually adjust from the original clumped distribution to a uniform scattered distribution. The best retention time is slightly after the peak shoot emergence period. The number retained should follow the required proportion of the bamboo forest structure, with the actual number retained being about 10% more than required by the bamboo forest structure. The specifications for retained mother bamboos are best based on the average bamboo size required by the forest structure, with an average diameter of 2-3cm being optimal, because at this time the bamboo forest's leaf area index tends to be reasonable and yield is highest.

3.3 Forcing Cultivation to Advance Shoot Production

Advancing shoot production can improve economic benefits. On the basis of applying shoot-gestation fertilizer and thoroughly irrigating with shoot-gestation water in November to December, cover the forest land in layers with weeds, rice straw, rice husks, etc. The covering thickness depends on surface temperature, generally about 15cm. After covering, the surface temperature should be controlled at 15-17°C, and strictly must not exceed 20°C. Through covering, the shoot period can be advanced by 20-50 days, and the shoot period can be extended by about 2 months, which is very beneficial for later retention of mother bamboos and bamboo forest growth.

4 Pest and Disease Control

The main pests and diseases prone to occurring in Bambusa multiplex groves include bamboo stem borers, aphids, and sooty mold, which must be detected early and promptly controlled using scientific methods. At the same time, cut and remove pest- and disease-infested bamboo, weak and small bamboo, and aging bamboo to facilitate ventilation and light penetration in the grove and reduce the occurrence of pests and diseases.