Facilitating the Removal of the Spray Residue

Abstract

A brief resume, concluded from practical and laboratory observations, is given of conditions that prevent the effective removal of spray residue by the chemical process. Of the factors that retard the solvent action, the settling of dust on the lead arsenate in the calyx and stem end of apples seems most difficult to overcome. In order to facilitate the removal of residue, numerous compounds were mixed with lead arsenate and applied to apples as a combination spray. The fruit sprayed with the various combinations were then treated in acid to learn what materials aided the solvent action of the acid.