AbstractAllozyme variation was analyzed in 180 individuals of Yushan cane from adjacent sun and shade microhabitats from three localities on Mt. Hohuan in Taiwan. Significant genetic differentiation according to microhabitat was found for both single and multi‐locus comparisons. Moreover, sun sub‐populations from different localities clustered together in a neighbor‐joining tree based on isozyme genetic distances, as did shade sub‐populations. These data not only imply significant local adaptation for different habitats in phenotypically plastic Yushan cane, but also suggest that diversifying selection is acting on allozyme loci or closely linked