- Group 1Lycophytes, Monilophytes
- Group 2Gymnosperms
- Group 3Monocots
- Group 4Woody angiosperms with opposite or whorled leaves
- Group 5Woody angiosperms with alternate leaves
- Group 6Herbaceous angiosperms with inferior ovaries
- Group 7Herbaceous angiosperms with superior ovaries and zygomorphic flowers
- Group 8Herbaceous angiosperms with superior ovaries, actinomorphic flowers, and 2 or more distinct carpels
- Group 9Herbaceous angiosperms with superior ovaries, actinomorphic flowers, connate petals, and a solitary carpel or 2 or more connate carpels
- Group 10Herbaceous angiosperms with superior ovaries, actinomorphic flowers, distinct petals or the petals lacking, and 2 or more connate carpels
Lactuca floridana (L.) Gaertn. was attributed to New England based on a collection from Eastham, MA ( Collins 1774 NEBC!). The specimen is L. biennis with apically pale pappus bristles (the basal half of the pappus bristles, the portion concealed by the involucral bracts, is light brown; L. floridana would have white pappus bristles). Lactuca saligna L. was reported from MA and ME by Strother (2006d), but specimens are unknown. Reference: Strother (2006d).
1b. Basal leaf blades linear to ovate, 0.6–12 cm wide; plants native or introduced, but not generally cultivated
2b. Cypsela apically with a slender, elongate beak 1–6 mm long [Fig. 430], the body ± flat; pappus ± white; capitula with 6–24 (–27) flowers; corollas yellow (sometimes blue in age or drying)
3b. Cypsela body brown to dark brown, with 1 prominent nerve on each face, sometimes with an additional pair of faint nerves [Fig. 430]; leaf blades not prickly setose
Show photos of: Each photo represents one species in this genus.