Field Trial of Salad Oil Application for the Induction of Male Flower Browning of Cryptomeria japonica

A field trial of salad oil application for the induction of male flower browning ofCryptomeria japonica was conducted. The browning effect of salad oil applied from a helicopter was found to vary from clone to clone depending on the earliness of male flower development. When applied at the flower initiation stage, salad oil turned male flowers to a brown color; when applied later, the browning effect of salad oil was not clear. The effectiveness of the application depended on how close to the time of flower initiation it occurred. The harmful changes caused by salad oil solution were only observed on the leaves of Japanese plume-grass (Miscanthus sinensis), and no other effects on other plants were observed.