- 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
Hordeum marinum Huds. ssp. gussoneanum (Parl.) Thellung was reported from MA by Hitchcock and Chase (1950), but specimens are unknown. Reference: von Bothmer et al. (2007).
1b. Anthers 0.5–1.8 mm long; leaf blades 1.5–5 (–7) mm wide; rachis disarticulating
Show photos of: Each photo represents one species in this genus.