Jepson eFlora
Key to families | Table of families and genera

Key to Mentha

View taxon page for Mentha

1. Calyx interior with ring of hairs; vegetative stems decumbent, flowering stems upright ..... M. pulegium

1' Calyx interior glabrous or hairs few, scattered; both vegetative and flowering stems upright

2. Inflorescence generally axillary

3. All leaves ± equal in size, blade generally ovate, generally spicy-scented ..... M. arvensis

3' Leaves reduced in size distally, blade generally linear to lanceolate, generally pennyroyal- or spearmint-scented

4. Leaves gradually reduced distally on stem, generally pennyroyal-scented ..... M. canadensis

4' Leaves greatly reduced distally on stem, generally spearmint-scented (fruit-scented)

5. Calyx 1.5–3 mm, lobes triangular ..... M. ×gracilis

5' Calyx 2.5–4 mm, lobes sharply tapering ..... M. ×smithiana

2' Inflorescence terminal

6. Inflorescence generally head-like, clustered at distal 3–5 nodes

7. Blade generally ovate, generally lavender- and citrus-scented ..... M. aquatica

7' Blade ovate to lanceolate, generally peppermint- or spearmint-scented (lavender and citrus) ..... M. ×piperita

6' Inflorescence spike-like

8. Leaves wrinkled

9. Blade lance-oblong, glabrous (branched-hairy abaxially), spearmint-scented ..... M. spicata (2)

9' Blade ovate, with scattered many-branched hairs abaxially, fruit-scented ..... M. suaveolens

8' Leaves not wrinkled, occasionally deeply veined

10. Blade lanceolate to lance-oblong

11. Blade widest near middle, hairs unbranched; fertile anthers ± 0.3–0.4 mm; generally musty-scented ..... M. longifolia

11' Blade widest near base, occasionally branched-hairy abaxially; fertile anthers ± 0.4–0.5 mm; generally spearmint-scented ..... M. spicata (2)

10' Blade oblong to ovate

12. Calyx ciliate; fertile anthers 4; leaf blade base tapered to ± lobed; corolla 2.5–3.5 mm; Great Central Valley, Central Coast, Transverse Ranges ..... M. ×rotundifolia

12' Calyx generally canescent; fertile anthers generally 0; leaf blade base tapered; corolla 3–4 mm; Transverse Ranges ..... M. ×villosa


Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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