Since 1972 a series of experiments were conducted to reveal physiological function and biological activities involved in rooting of mulberry cuttings, and the behaviour of ether extractable growth control substances in leaves and stens. Measurements were made on various mulberry varieties for respiration of cuttings, suitable size for the production of cuttings, change of rootability of cuttings with growth of cutting shoots after cutting date, rooting tests on the green beans with ether leaf extract and ether stem extract, and rooting effect of cutting by NAA treatment. (omitted)