This is a preliminary study of a group of North American taxa of Lecanora occurring on bark and containing usnic or isousnic acid and having a yellow, yellow-green, or greenish thalli. The group is regarded as L. varia s. lato and, based on species examined, a proposal is offered to delimit the following smaller groups: L. varia group s.str.; L. expallens group s. lato with L. strobilina and L. expallens group s.str.; and the L. saligna group. Two new subspecies (L. varia subsp. densa and L. varia subsp. laxa) are described. A key for the taxa studied is presented. Some suggestions for future research are outlined.