In addition to the usual boron excess symptoms, observed for many years in California, deficiency symptoms have been identified in Yolo County almond orchards in recent years. Shoots and branches die back, nuts become gummy and drop or leaves scorch and curl up at the tips. The condition may be corrected, however, with either soil or spray applications of materials containing boron.

Farm Advisors C. V. Carlson of Merced County, D. M. Holmberg of Yolo County and H. C. Meith of Butte County co-operated. Omund Lilleland, Pomologist, University of California, Davis, made available results from his plot in Merced County.

The above progress report is based on Research Project No. 1097.