By the application of detillering treatment the following results were obtained: (1) In Oryza sativa, aerial branching was induced in 75% of the treated plants; (2) In Hordeum distichon, aerial branching and/or stachying phenomenon was induced in 84% of the treated plants; (3) In Triticum turgidum, the stachying character was evidently strengthened; (4) In T. monococcum and T. dicoccum, the increase of the floret number in each spikelet was induced in almost 100% of the treated plants. (5) The development of these plants was accelerated, the plants became more robust and bore more seeds. This is most evident in the wheats. The height of these plants and especially the length of the distal internode were shortened. It is suggested that the results mentioned above may be due to the redistribution of nutrients after detillering and that the changes induced are merely a kind of phenotypic variations to accommodate the detillering treatment.