N 
is . 
F-520107 
Figure 201.—Heavy infestation of galls on twigs of 
Nuttall oak in the Mississippi River Delta region. 
Callirhytis quercuspunctata (Bassett), the gouty oak gall, occurs from southern 
Canada to North Carolina and west to Illinois. It induces galls (fig. 202) on the 
twigs and smaller limbs of scarlet, pin, and black oaks. These galls are about 12 to 
38 mm long and they frequently occur so close together that they form practically 
continuous masses. C. quercuspunctata has alternate generations. The first induces 
small blisterlike galls on the leaves near the veins in the spring. The second induces 
gouty galls during the summer. In heavy infestations, twigs, fairly large branches, 
and even entire trees may be killed. Shade trees are especially subject to damage. 
Callirhytis cornigera (Osten Sacken), the horned oak gall, occurs from southern 
Canada to Georgia and west to Iowa. It induces galls on the twigs of pin, scrub, 
black, blackjack, and water oaks. Injurious infestations have been observed on 
roadside and woodland oaks in the Niagara area of Canada. 
Callirhytis quercusgemmaria (Ashmead), the ribbed bud gall, occurs from 
Massachusetts to Florida, and west to Illinois. It induces somewhat conical, 
strongly ribbed galls about 5 mm long on the twigs of black oaks. These galls 
sometimes occur in such large numbers as to cause infested twigs to split and die. 
Entire young trees are sometimes killed. 
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