Abnormal vine growth found in certain California vineyards—short basal internodes, zigzagged shoots, witches broom formations, scarification, flattened canes, dead overwintered buds-results in a reduced crop.

This study of the seasonal cycle has not revealed a weak point where the mites ore sufficiently exposed to be controlled by ordinary sprays. The finding of mites and mite riding injury on the primordial clusters at the center of grape buds adds considerable support to their being a cause of dead Over wintered buds