Jepson eFlora
Key to families | Table of families and genera

Key to Mentha

View taxon page for Mentha

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

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

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [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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