Wood Anatomy and Growth-ring Boundaries of Selected Miombo Woodland Tree Species in Eastern Tanzania

Abstract Dendrochronological studies in tropical regions remain limited due to uncertainties surrounding the formation and distinctiveness of annual growth rings. This study assessed the growth-ring distinctiveness and wood anatomical characteristics of selected dominant Miombo woodland tree species in eastern Tanzania, to evaluate their dendrochronological potential. The study was conducted in Kitulanghalo Forest Reserve, which is located in Morogoro Rural District, in Morogoro Region. Non-destructive increment core sampling was used to extract samples from adult individuals of Brachystegia boehmii , Julbernardia globiflora , Senegalia nigrescens , Combretum molle , and Combretum zeyheri . Macroscopic examination of polished transverse surfaces and microscopic analysis of histological sections were employed to describe growth-ring boundaries and associated anatomical features. The results revealed that Brachystegia boehmii , Julbernardia globiflora , and Senegalia nigrescens form distinct and continuous growth-rings, marked by changes in vessel size, vessel frequency, fibre characteristics, and terminal parenchyma, indicating strong dendrochronological potential. In contrast, C. molle and C. zeyheri displayed indistinct or discontinuous growth rings, limiting their suitability for reliable age determination. The study concludes that several Miombo species in eastern Tanzania are suitable for dendrochronological studies, while others require cautious interpretation. These findings provide a foundation for future cross-dating, climate growth analyses, and the development of sustainable forest management and harvesting strategies in Miombo woodlands.