Diffusion of 14C-Flurprimidol in Various Carriers Through Excised Silver Maple Bark
David A. Breedlove, Michael E. Foley, Harvey A. Holt and William R. Chaney
Abstract: Bark banding is one alternative to trunk injection of tree growth regulators (TGRs). The objective of this study was to compare the penetrability of various oils as carriers for a TGR applied to the bark. Five p.l of 14C-flurprimidol (225,000 dpm) and unlabeled flurprimidol dissolved in isopropyl alcohol and selected oils (Androc Basal Oil, ArborChem Basal, Arborchem Clean Cut, CWC Hy-Grade I, Exxon Aromatic 200, Exxon Orchex 796, Leffingwell Carrier #9, and N.G. Gilbert Riteway Oil) were applied to bark excised from silver maple (Acer saccharinum ). Bark discs, 1.35 cm diameter, were sealed in a diffusion chamber and the rates and amounts of 14C-flurprimidol that moved through the bark were measured by liquid scintillation spectrometry. Rate of diffusion, measured as dpm/day for nine days, was similar for each oil. The pattern of penetration was an initial flux the first 24 hours followed by a diminished rate of penetration by the end of day two and a gradual increase during the next seven days.