Improving productivity of a previously unmanaged Bambusa blumeana plantation for culms and shoots in Ilocos Norte, the Philippines

The productivity of a previously unmanaged Bambusa blumeana (kawayan tinik) plantation was assessed over 5 years. We studied the combined effects of cleaning, irrigation, application of inorganic fertiliser, mulch and organic matter, and varying culm density regimes on the production of good-quality culms (poles) and shoots. Generally, irrigation significantly improved the productivity index, shoot emergence and number of shoots per clump. The average shoot production of six shoots per clump from all treatments is within the range of shoot production of B. blumeana in areas with distinct dry and wet seasons. The clumps that received irrigation during the shoot stage had culms with a significantly larger diameter than those without irrigation. The older culms (3 and 4 years) produced far fewer shoots than the younger ones, hence it is better to harvest these culms for pole production rather than rely on them for shoot production. The combined effect of the various silvicultural operations with three, four, or six culms per age group was not consistent for growth response, but the quality of culms in the clumps with 16 culms per clump (four culms of each age group; 1, 2, 3 and 4 years) produced the highest number of culms and most superior strength properties. Extending the age of the culms from 3 years to 4 years improved their physical properties appropriate for construction purposes.Overall, this study provided a strategy by which it is possible to predict productivity of B. blumeana clumps in terms of both culms and shoots by retaining specific numbers of different-aged culms. Combined with other silvicultural treatments, this should allow both natural stands and unmanaged plantations to become productive in a way that is sustainable.