In substantial abundance, bamboos coexists with trees in primary tropical rain forests in South East Asia. Counter to common understanding that bamboo is a taxon of disturbance dependent and fast growth, some bamboo species distribute throughout a wide range of habitat condition from under closed canopy to highly disturbed stand. As they are morphologically and life-historically disparate from trees, it is not readily reasonable to incorporate bamboos in prevailing framework of plant interaction theory and coexisting mechanisms. To approach the cross-morphological theory, it is indispensable to compare their morphological characters, growth patterns, and life-histories. In this seminar, I compare the morphological characters of bamboos (Gigantochloa ligulata and Schizostachyum grande in Peninsular Malaysia) and trees (from Yamakura 1986 in East Kalimantan), and reveal the difference of biomass partitioning strategy. The estimation of bamboo architecture and size information partly incorporated the repetitive geometric pattern as an assemble of internodes. Assuming functional equivalence for tree stem and bamboo culm, and for tree and bamboo branch, global rules of tree allometries didn’t fit bamboo for the following allometric relations: H ∝ Wtotal^1/4; Wleaf ∝ Wtotal^3/4, while Wtotal ∝ D^2H was not different. Bamboos showed less-cost architecture to distribute foliage than trees, relying more on branching than culm (stem). High turnover and short longevity of bamboo lamet and insufficient height of shoot to penetrate forest canopy is likely compensated and defeated by flexible and low-cost branching strategy. This characteristics may have an advantage in stochastically disturbed stands such as matured forests, and in stand on steep slope where horizontal approach to penetrate canopy is effective.