Effects of Substituted Phenoxy-Compounds and other Translocated Herbicides on the Rhizome of Bracken

IT is now widely recognized that the food reserves in the underground stem of bracken, Pteridium aquilinum, are often greater than was formerly realized, and that defoliation, even if prolonged, is frequently insufficient to kill the growth-centres1–3. Since the underground stem is the organ of growth and extension as well as of perennation, control of the plant's development should be sought by direct rather than indirect control of such an active and massive organ.