INVESTIGATIONS ON SKELETON WEED ( CHONDRILLA JUNCEA L.) WITH PICLORAM AND 2,4‐D

Summary. Picloram is decarboxylated to a negligible extent in roots of skeleton weed: applied to leaves it kills roots better than 2,4‐D; it penetrates leaves better than 2,4‐D and disrupts the translocation system more, does not leak considerably into the soil from roots by the time of appropriate harvests, yet is not as well translocated as 2,4‐D. Under such conditions its ability to kill roots to a greater depth is attributable to its greater intrinsic toxicity. There is some evidence that under certain field conditions useful movement or uptake of picloram may occur via the soil. Recherches sur Chondrilla juncea L . avee le plclorame et le 2,4‐D.