Bamboo is one of the commercially cultivated crops and this is considered as a “poor man’s timber”. In Asia, bamboo is the most integrated part of the culture and used as wood substitute. Bamboo is mainly used as construction material, furniture, pulp and plywood. Bamboo shoots are consumed as a food and they are good source of nutrition. There are 33 species of Bamboo found in Bangladesh.
Sonali, kolsi, Botol, Kali, Rongon, Konchi, Tents, Borua, Budum, Muli, Tolla, Borak, Biazza, Bethua, Farua, Ora, Lota mirtinga etc.
Bamboo plantation grow well in tropical to warm temperate climatic conditions. However, it does not prefer temperatures under 15°C in summer. As the bamboo has shallow roots & luxuriant growth, there should be a provision of protecting from strong winds. Regions with cold winds are not suitable for its growth as the wind kills the tips of bamboo leaves.
Bamboo can be grown in wide range of soils except in rocky soils. Bamboo plantation requires well drained sandy loam to clay loam soils with pH range of 4.5 to 6.0.
The land should be ploughed as thoroughly and deeply as possible. Clearing and ploughing should be done at least 3 weeks ahead of the planting. Provide better drainage system. Bamboo likes water and requires lots of water to do its best, but it does not like to be submerged in water.
Generally, Bamboos are propagated through culms cuttings or rhizomes. They can also be propagated through seeds. However, bamboo seeds are very rarely available. Bamboo seedlings are raised on nursery beds and they are allowed to grow in poly pots for a year. Then this seedling will be transplanted into the main field. In rhizome planting method, 1 year age culms with roots should be dug and cut to 1 meter height. These culms should be planted in monsoon (rainy season). If bamboos are propagated through rhizomes, extra care should be taken while planting the rhizomes. In most of the places, vegetative propagation method is practiced.
Planting and Spacing
Usually, bamboo planting is preferred in rainy season. Pits should be dug much before the rainy season and the dug out soil exposed to weathering. The pits size of 60 X 60 cm should be dug and nursery raised seedlings (1 year old) should be planted at distance of 5m X 4m. The density or the number of plants of bamboo accommodated in 1 acre is about 200. A few days before planting thoroughly turn the soil in the pit.
In bamboo plantation the gestation period is 5 years. The inter space can be used during first 3 years for extra income by cultivating inter crops like ginger, chillies and turmeric. Even any shade loving aromatic or medicinal plants can be grown.
It is better to carry out soil analysis to fix and confirm the dosages. A general dosage normally that may be followed is (Plant/year).
▲ Urea: 15.5 kg. ▲ SSP: 5.5 kg. ▲ MoP: 13.45 kg.
For first year 50%, second year 75% and third year onwardsfull dose should be given in 10 split doses. Fertilizer application is required to be done first during planting. The fertilizer should be mixed in the pits. Subsequently, fertilizer should be applied every months of planting. Care should be taken to see that chemical fertilizers are not applied directly.
Mulching: The growth of the weeds controlled by mulching apart from retaining the soil moisture. All transplanted plants should be mulched with 20 cm depth of straw or hay and a diameter of 2m. To protect from drying the soil, spread the soil on top of mulch.
Weed Control: Hand weeding and hoeing should be carried out for controlling the weeds. Mulching will also control the weeds. As sun light causes for more weed growth, providing shade on the ground and lowering the temperatures can check out the weeds.
Mounding: Rhizomes grow laterally under the soil surface and when ready to throw up shoots, begin to grow upwardly inclined angle as well. In this period of growth, exposure to sunlight retards and may even stop the growth of rhizomes. Mounding or heaping fresh, loose soil around and over the base of the plant is recommended.
Pruning: In some species there is heavy branching at the lower nodes of the plant. For example Dendrocalamus hamiltonii and Bambusa balcooa. Pruning of these branches reduces clump congestion and helps provide a healthy, airy environment within the clump. Mild pruning should be done in the second and third years of growth, and intensive pruning from the fourth year onwards. It should be completed before the end of the dormancy period, well before shoots emerge. Pruning should be carried out in the month of December and January.
Cleaning: Generally clump formation starts in third year, the management of clumps are very important. Rhizomes grow centrifugal (outwards) throwing up new shoots in enlarging circular formation. Bamboos can throw up many branches, which if left unattended can get deeply entangled. This not only curbs access to older culms towards the center of culm, but also obstructs free vertical growth of new culms. The new culms may get twisted and turned, which further congest the clump. Such malformed culms make harvesting of the better culms difficult. Therefore, it is important to clean clumps early and to remove all dead and malformed culms. A well aired clump results in the emergence and growth of healthy culms. Dead stems are not only vulnerable to pathogens, but also dry up fast and are a potential fire hazard.
A good time to carry out clump cleaning operations is February – March. In this period of dormancy after the rigors of winter are over and before the cycle of active growth begins again, the plant system is better prepared to withstand the stress of cleaning activities.
Thinning: Thinning the clump is essential from third year onwards to avoid congestion and to ensure proper growth and easy extraction of culms. Weak and deformed culms should not be retained in the culm. An appropriate clump structure should be maintained through thinning as well as through extraction or retention of shoots.
In bamboo planting, irrigation should be carried out frequently while they are grown on nursery beds. Immediate irrigation should be given at the time of transplanting seedlings from nursery to main field. As bamboo trees are sensitive to water logging, make sure to drain out the soil in case of heavy rains or flooding. Subsequent irrigations depend on the soil moisture holding and climatic conditions. It’s preferred to let a plant go a little dry and water it. A drip irrigation system can be adopted for better utilization of water. Over watering will make the tips of leaves to turn into brown.
After planting, irrigate with 12-20 litres of water, depending on the prevailing climatic conditions and compact the loose soil around the plant. Repeat the watering the next day. For the next 10 weeks (at daily intervals initially, extending later to once in three days).
Pests and Diseases
Following are the pests and diseases control measures in Bamboo Cultivation. Leaf biting & sucking insects are common pests in young bamboo plantation. Appropriate pesticides should be applied to control these pests.
Main diseases found in bamboo plantation are Fusarium moniliforme, var. intermedium, F. equiseti and culms blight. Appropriate chemical control measures should be taken care to control these diseases.
Harvesting of bamboo culms every year will induces the emergence of new shoots and ensures regular and healthy culm production. In bamboo cultivation, the harvesting can be carried out from 5th year onwards. However, in commercial farming, harvesting should be carried out from 6th year. In the first year of harvest i.e. 6th year, 6 culms/clump can be harvested followed by 7 culms in 7th year, 8 culms in 8th year and 9 culms from 9th year onwards. Generally, the 1 or 2 year old culms are left for regeneration.
Harvesting Time: The best time of the year to harvest culm is in the post monsoon season extending through the winter. This is the period of dormancy during which culms tend to have lower starch content. They are therefore less susceptible to borers, termites and other pests. Culms should not be harvested in the growing season, which is normally during the monsoon months. Harvesting in this period can damage young and emerging shoots and retard the future growth of the clump.
Generally, the annual yield of bamboo depends on the species and as well as environment. An average weight of culms at 10 kg, the yield in the 1st year is about 9.5 to 10 tonnes/acre which will stabilize at about 14.5 tonnes per acre in 9th year.