By Ranger Naturalist Clyde C. Searl

SINCE CITRICOLA scale, whose host is hackberry, has recently become a menace to citrus growth in southern California, Mr. Stanley H. Flanders of the Citrus Experiment Station, Riverside, California, has just made a trip through Arizona, Utah, and Nevada, to examine native hackberry for the presence of this scale. At Grand Canyon the writer was privileged to accompany him down the Bright Angel Trail during his examinations. The first bushes of hackberry to be found were near the base of the Supai formation, and on them two species of common scale were collected. These were later determined as Pulvinaria vitis and Lecanium corni. Both have been reported before on hackberry, the latter from the United States as far north as Canada and as far east as Indiana. Pulvinaria vitis occurs on hackberry in Zion National Park, Utah, near the temple of Sinawava.