Fiber Morphology of Solid Bamboo [Dendrocalamus strictus (Roxb.) Nees] and Iron Bamboo (Guadua angustifolia Kunt.) Grown in the Philippines: the Influence of Locality, Axial Height, and Presence of Node

The study examined the effect of locality, axial height, and presence of node on the fiber morphology and derived ratios of iron bamboo (Guadua angustifolia Kunt.) and solid bamboo [Dendrocalamus strictus (Roxb.) Nees] grown in Laguna, Baguio City, and Nueva Vizcaya. It focused on characteristics such as fiber length, fiber diameter, lumen diameter, and cell wall thickness, along with derived ratios like the runkel ratio (RR), flexibility ratio (FR), slenderness ratio (SR), mulhsteph ratio (MR), and rigidity coefficient (RC). The results showed that species, location, axial height, and node presence significantly influenced fiber morphology and derived ratios. Specifically, solid bamboo had 22% longer fibers, whereas iron bamboo exhibited 17% thicker fiber diameters and 25% thicker cell walls. In terms of location, iron bamboo from Laguna had significantly thicker fiber (23.82 μm) and lumen diameter (8.86 μm) compared to samples from Baguio (21.77 and 5.12 μm, respectively) yet with thinner cell walls (7.48 μm). Conversely, solid bamboo from Nueva Vizcaya showed thicker fiber dimensions than those from Laguna. Along the axial heights, fiber characteristics displayed significant variations, with distinct trends observed across properties. Samples without nodes demonstrated significantly longer fiber lengths, whereas other traits were lower. Derived ratios varied considerably within species across localities. However, both species scored 25 (class III) for the RR, FR, MR, and RC, indicating their suitability for pulp and paper production with the need for additional chemical processing. However, their SR values exceeded the threshold of > 35. The FR values and fiber length suggest these bamboo varieties' potential for use in composite materials.