Twig blight of landscape oak trees was reduced to an acceptable level by pruning or by pruning plus treatment with a fungicide.

The authors thank C. S Koehler, A. H. McCain, R. D. Raabe, and F. W. Cobb, Jr., for many helpful suggestions, G. Slaughter and F. Determan for their help with the field work, C. Sauer (California Conservation Corps Nursery, Napa, California) and the Saratoga Horticultural Foundation for supplying many oak seedlings, the Stanford Grounds Department personnel for making the field study possible, and D. Rowney for statistical analysis of the data. Funds were provided by the Elvenia J. Slosson Endowment Fund.