Prolonging Dormancy of Tung Trees with Spray Oil and Succinic Acid-2,2-Dimethylhydrazide1

Abstract

Abstract Naphthenic oil with and without succinic acid-2,2-dimethylhydrazide (SADH) was applied to dormant tung trees in February or early March to delay bloom in the spring. A late frost occurred in March 1968; the only branches of the trees to flower and set fruit were those that were treated with napthenic oil and oil with SADH. By contrast, branches treated with aqueous SADH were not saved. In 1969, branch sprays of 10% oil with 1% SADH resulted in delaying bloom up to 5 days and in setting more fruit than the control. In 1970, sprays of 50% oil with 2% SADH delayed bloom on 5-year-old tung trees by approx 2 weeks.