Causing deformation of fruits ("bladder plums," "plum pockets") and of twigs, sometimes with curling of leaves (not witches' brooms) of Prunus americana Marsh. P. [americana var.] lanata (Sudw.)
Mack, and Bush, P. hortulana Bailey ... P. maritima Marsh., P. rnunsoniana Wight and Hedr., P. nigra Ait., P. salicina Lindl., P. tarda [umbellata], P. umbellata

T. mirabilis, a species parasitic on Prunus angustifolia, was considered synonymous with T. communis by Mix (1949), but the results of the molecular characterization suggest otherwise ... although a final decision would benefit from additional data

[Gallformers is following Mix, pending further developments]