One of The More Serious cultural problems in the growing of almonds in California is the poor set caused by the lack of cross-pollination during certain climatic conditions. This is especially true in some years when bloom periods do not overlap much. Since almonds bloom early, spring frosts (to which open flowers are susceptible) may also reduce fruit set. To explore the possibility of controlling the time of flower opening, preliminary trials where made in 1966 with the synthetic growth retardant, Alar. (Alar is not registered for commercial use on almonds.) These trials indicated that this compound not only reduces shoot elongation, but also extends the winter dormancy in almonds, thus delaying the opening of the blossoms.

The plot of trees used in these trials was made available through the cooperation of Mr. Ioppini of Manteca and the Manteca High School District.