In much the same diverse habitats as L. biennis: borders and trails in forests; promptly invading disturbed sites and clearings; sandy pine plains, conifer swamps, rocky ground, shores, fields; roadsides and railroads.

This species and L. biennis are the two widespread common native wild lettuces in Michigan, and they can be easily separated by pappus color: silky white in L. canadensis and dark in L. biennis. The two species are known to hybridize but presumed hybrids, with intermediate characters, are apparently quite scarce in Michigan.

Some plants have many of the leaves unlobed and ± lanceolate, but usually the leaves are all or mostly lobed and the lobes tend to be narrowly lanceolate in contrast with the broad lobes in L. biennis. The foliage is amazingly variable in both species.