A laboratory study to explore the effect of vegetation in terms of rigid cylindrical roughness on the hydraulics of flow in an open channel is presented. The study consists of an extensive set of flume experiments for flows with unsubmerged rigid cylindrical stems of various concentrations arranged in regular staggered configurations. The study will be helpful for finding roughness and local velocity in a channel with rigid vegetation. The effect of emergent rigid vegetation on the prediction of the effective vegetal drag coefficient, Cd for various flow depth combinations has been explored. Vegetal drag coefficient Cd is found to vary with the non-dimensional hydraulic, geometric and surface parameters such as vegetation densities, relative depth ratio of water depth h to plant height hs, Reynolds's number Re and Froude's number Fr etc. The suitable dependencies of the vegetal drag for the non-dimensional hydraulic and geometric parameters are presented. Analysis and comparisons with flexible vegetation has also been done with the present experimental work on rigid vegetation. Parameters affecting the velocity drag coefficients for both the cases are discussed, compared and results are summarized and presented