Neolamarckia cadamba (Roxb.) Bosser locally known as 'Kadamba', is a tropical tree species native to South Asia and Southeast Asia, including India. It is a large tropical tree with broad a crown and straight cylindrical bole having an average height of 15 meters with self- pruning ability. Under favorable climatic conditions, this tree attains a height of 20 m or more with a clean bole of about 9 m and a diameter of 40 to 60 cm. In Assam, the tree attains a height of 6.5 m and diameter of 12.7 cm at 4 years (Ghosh, 1977). The rate of growth is very fast in the earlier years, the height increment averages 3 m per annum for the first six or eight years after which the growth slow up to 20 years and thereafter becomes very slow. This species is increasingly important for wood- based industries. Wood of this species is suitable for multiple end uses, such as plywood, light construction materials, flooring, beams and rafters, boxes and crates, tea-chests, packing cases, shuttering, ceiling boards, toys, wooden shoes, bobbins, yokes, carvings, matches, chopsticks and pencils (Soerianegara and Lemmens, 1993). This species is expected to become highly important to meet the gap between demand and supply of raw materials for pulpwood, matchwood, pencil and plywood wood-based industries. There is already a high demand for pencils, plywood and match splints in India. Although, the species is indigenous, fast growing with multiple uses, it has received little research attention and there is no tree improvement programme for this species. The objective of the study was to access the anatomical properties of N. cadamba wood at different ages.

Species Name: Neolamarckia cadamba (Roxb.) Bosser

Sample collection

Destructive sampling method was adopted to collect the wood samples across the different ages. Twelve trees per age was taken and averaged.

Table 1: Fiber morphology of Neolamarckia cadamba at different ages

Table 2: Axial variation of fiber morphology of Neolamarckia cadamba wood at different ages (replicates of four)

The fibre morphology of Neolamarckia cadamba exhibited significant variation across different ages (2–10 years), particularly in fibre length, diameter, lumen width and wall thickness (Table 1). Fibre length ranged from 1463.25 µm at 4 years to 1854.16 µm at 10 years, showing an overall increasing trend with age despite minor fluctuations. The increase was more pronounced from 6 years onward, indicating enhanced fibre development during later growth stages. Fibre diameter also showed a gradual increase with age, reaching a maximum of 44.56 µm at 6 years before slightly declining at older ages. The statistical analysis (CD = 1.89) confirms significant differences among age classes (Table 1).122ibre lumen width initially increased from 29.20 µm at 2 years to 32.78 µm at 6 years, followed by a decline to 26.26 µm at 10 years, suggesting increased secondary wall deposition in older wood. In contrast, fibre wall thickness showed a clear increasing trend, particularly at 10 years (8.67 µm), indicating strengthening of fibres with maturity. All these variations were statistically significant, highlighting the influence of age on fibre characteristics (Table 1).Axial variation within the tree revealed a consistent pattern across all ages (Table 2). Fibre length was highest at the base and lowest at the top, with significant differences observed along the stem. For instance, at 6 years, fibre length decreased from 1909.55 µm at the base to 1627.59 µm at the top, reflecting the maturity gradient along the stem. However, fibre diameter, lumen width and wall thickness did not show significant axial variation (NS), although numerically they tended to decrease from base to top (Figure 1).

Fibre length is a critical property influencing fibre bonding and strength, as longer fibres form stronger networks (Johansson, 2011). In the present study, fibre length ranged from 1463.25 µm to 1854.16 µm, with values at 6, 8 and 10 years not significantly different. Although no strict linear trend was observed, fibre length generally increased with age. The values recorded were higher than several species such as Eucalyptus camaldulensis (670 µm) and Eucalyptus globulus (716 µm) and Melia dubia (936.60 µm) (Saravanan et al., 2013), Albizzia chinensis (1147 µm) (Darmawan et al., 2013) and young teak wood (Wahyudi et al., 2014). Axially, fibre length varied significantly, decreasing from base to top, consistent with findings in Ricinodendron heudelotii (Ogunleye, 2017), Moringa oleifera (Ekhuemelo et al., 2016) and Eucalyptus tereticornis (Uniyal, 2012).

The present study demonstrated that fibre morphology of Neolamarckia cadamba is significantly influenced by age, with comparatively lesser variation along the axial positions of the stem. Fibre length, diameter and wall thickness generally increased with age, indicating progressive maturation and improved mechanical strength of wood. In contrast, fibre lumen width showed variable trends, reflecting changes in cell development and wall deposition. Axial variation revealed that fibre length decreased from base to top, while other parameters remained statistically non- significant, suggesting relative uniformity within the stem. The results indicate that intermediate ages (6–8 years) provide a balance between fibre strength and desirable processing characteristics. N. cadamba exhibits favourable anatomical properties suitable for pulp, paper and other wood-based industries.