Eriophyes vitis, feeding on embryonic tissue of grape buds or shoots, causes hypertrophy of the cells fed upon and later, the formation of scar tissue. This injury, when extensive, results in malformation of the maturing structure. Other organisms or conditions interfering with the normal maturation of tissue may account for deformations similar to those produced by E. vitis feeding. The possibility of economie losses due to E. vitis is normally minimized by the propensity for the mites to feed primarily on the scales of overwintering buds and by the reduction of their numbers on new shoot growth by factors such as predation and possibly climate. E. vitis injury in commercial Tokay vineyards which were studied did not cause a commercial loss, However the effect on vine in the shoots sufficient to cause boron toxicity symptoms had little or no adverse effect on mite populations. 2) Mites were able to cause typical injury to shoots with high as weil as low boron content. 3) The symptoms produced by the mites were distinct from those produced by boron excess. The classic symptoms of boron excess syndrome were identified by Dr. J. A. Cook, and the syndrome of mite injury was identified by the authors.