Tall Blue Lettuce (Lactuca biennis) vs. Canada Lettuce (Lactuca canadensis)
Updated April 15th, 2023Lactuca species have notoriously variable leaf shapes. These two species are often confused by people unfamiliar with them, but they are usually easy to tell apart, especially when they are blooming or making seeds. There is significant overlap in habitat, and plants can often be found growing side-by-side, but L. biennis is slightly more shade-tolerant and more restricted to partly-shaded, moister habitats, whereas L. canadensis also ventures into drier, sunnier conditions, and ranges much farther south.