Bamboos are the tallest and largest of the grasses distributed both in the hills and plains of India. In general, the genera Bambusa and Dendrocalamus naturally occur under tropical conditions. Demand for bamboo is increasing both from industries as well as for commercial purposes.
Natural forests have been the main sources of bamboos so far, but over exploitation of these forests have led to decrease in its production. Bamboos are commonly used as agricultural implements, anchors, arrows, boats, chairs etc. Scenario of increasing demand, decreasing supply, assured marketability makes cultivation of bamboo on private lands an attractive economic proposition. Intensive management of monocultural stands play vital role for maximizing production in a unit area. Growth and yield of bamboo depends upon source of planting materials, method of planting and spacing.
The main management practices like spacing and fertilization directly affect the productivity of bamboo. Clump and culm spacing are considered to be important techniques for production of higher marketable poles. An effort has been made to study the optimum spacing for bamboo for high productivity.
Materials and Methods:
An experiment to study influence of spacing on growth of bamboo was initiated during 1977 under rained conditions on red gravelly soils at the main campus, University of Agri-sciences, Dharwad. The seedlings were planted at three spacing viz., S1. 1.0 x 1.0 M, S2. 1.8 x 1.8 M and S3. 3.0 x 3.0 M in randomized black design with twelve replications. Fertilizer doze of 100 : 500 : 60 N, P2O5, K2O kg/ha was applied in two split dozes i.e., 50% at the time of planting and remaining after 6 months of planting. Mature culms were harvested every year during the summer.
The pooled data for the 5 years (1990-1995) is presented in Table 1:
Results and Discussion:
Bamboo planted at wider spacing (3.0 x 3.0 M) had significantly higher number of internodes per culm (21.6) than S2 (20.2) and S1 (19.1). Culm girth also followed the same trend. The internodal length and culm length were not significantly influenced by different spacings. However, the maximum values for the internodal length and culm length were recorded in wider spacing.
The dry weight of culm was significantly higher in wider spacing (2.25 kg/culm) than narrow spacing (1.63 and 1.97 kg/culm). The percentage of increase in dry weight per culm with wider spacing (S3) was 12 and 32 over S2 and S1 respectively.
Total number of culms per hectare was significantly higher (48249/ha) in narrower spacing (S1) than in S2 (26365/ha) and S3 (22137/ha) which were on par with each other. Dry weight of culms per hectare followed the same trend. The increase in dry weight of culms per hectare in narrower spacing (S1) over S2 and SS was 29 and 33 per cent respectively. Similar results were obtained by Nodas (1982) and Suri and Choudhari 1994.