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1 Leaves 2- to 3-ternately compound; [tribe Spiraeeae] |
1 Leaves 1-compound, either simply pinnately compound or simply palmately compound, |
..2 Principal (basalmost) leaves pinnately compound, with (3-) 5-many leaflets (upper stem leaves sometimes 3-foliolate). |
....3 Principal leaves with leaflets of markedly disparate shape and size (large leaflets alternating with much smaller leaflets, or a large terminal leaflet and much smaller lateral leaflets). |
......4 Lateral leaflets alternating between small and large, the terminal leaflet similar in size and shape to the larger lateral leaflets; terminal leaflet < 3 cm wide; hypanthium either conical or turbinate, armed with hooked bristles, the pistils 2, or hemispheric, the pistils >5. |
........5 Leaves glabrous or sparsely pubescent beneath; flowers many in racemes; hypanthium conical or turbinate, armed with hooked bristles, the pistils 2; [tribe Sanguisorbeae] |
........5 Leaves silvery sericeous beneath; flowers solitary and axillary; hypanthium hemispheric, the pistils >5; [tribe Potentilleae] |
......4 Leaflets variable in size and shape, usually the terminal leaflet much larger than any of the lateral leaflets; terminal leaflet 3-20 cm wide; hypanthium either sauce-r-shaped or hemispheric to conical; pistils 5 or more. |
..........6 Pistils 5-15, in a circle on a saucer-shaped hypanthium, ripening into upright fruits that resemble follicles but are indehiscent; corolla white or pink; plant 10-20 dm tall; [tribe Ulmarieae] |
..........6 Pistils many, densely covering the hemispheric to conical hypanthium, ripening into achenes terminated by the persistent style; corolla white, cream, pale yellow, bright yellow, lavender, maroon, or purple; plant 2-10 dm tall; [tribe Colurieae] |
....3 Principal leaves with leaflets of generally similar shape and size (the lowest leaflets may be smaller but of similar shape and toothing to the other leaflets). |
............ 7 Stems and leaf rachises and petioles armed with retrorse prickles. |
............ 7 Stems and leaves unarmed. |
............ ..8 Foliage and stems viscid-pubescent with brownish hairs; inflorescence a cyme; petals 5, cream-colored; [tribe Potentilleae] |
............ ..8 Foliage not viscid-pubescent (if hairy, the hairs not brown or viscid); inflorescence of very many (>100) small flowers in a spike, the rachis hidden by the tightly packed flowers; petals 0; [tribe Sanguisorbeae]. |
............ ....9 Leaflets pinnatifid (each leaflet incised nearly to the midvein); stamens 2 or 4 per flower |
............ ....9 Leaflets toothed (the incisions not nearly to the midvein); stamens either 4 or 15-20 per flower (in well-developed, staminate flowers). |
............ ......10 Leaflets 0.8-2 cm long; spike 1-2 cm long, 1-2× as long as broad, globose; stamens 15-20 per flower (in well-developed staminate flowers), the filaments 3-4 mm long; sepals green to pinkish-purple; [cultivated, occasionally escaped] |
............ ......10 Leaflets 3-10 cm long; spike 6-30 cm long, elongate; stamens 4 per flower, the filaments 8-10 mm long; sepals white (sometimes fading greenish); [native] |
..2 Principal (basal-most) leaves palmately compound, with 3-7 (-9) leaflets. |
............ ........11 Principal leaves subsessile, 3-foliolate; fruit of follicles; leaves cauline; [tribe Gillenieae] |
............ ........11 Principal leaves distinctly petiolate, the petiole often longer than the leaflets, 3-7 (-9)-foliolate; fruit of achenes; leaves basal and cauline. |
............ ..........12 Principal leaves 5-7 (-9)-foliolate; [tribe Potentilleae] |
............ ............ 13 Petals maroon-colored, shorter than sepals; plants sprawling with horizontal stems bearing rooting nodes; [wetlands from n. PA, n. NJ, sc. IN and sc. OH northward] |
............ ............ 13 Petals yellow or white, not shorter than sepals; plants trailing or upright, if bearing horiztonal stems with rooting nodes then petals not maroon-colored and plants not in wetlands; [dry habitats, collectively widespread] |
............ ..........12 Principal leaves 3-foliolate. |
............ ............ ..14 Plants in flower. |
............ ............ ....15 Petals yellow. |
............ ............ ......16 Pistils 2-6; [tribe Colurieae] |
............ ............ ......16 Pistils (10-) numerous; [tribe Potentilleae] |
............ ............ ....15 Petals white (or slightly pinkish). |
............ ............ ........17 Calyx lobes not subtended by bractlets; [tribe Rubeae] |
............ ............ ........17 Calyx lobes subtended by 5 sepaloid bractlets; [tribe Potentilleae]. |
............ ............ ..........18 Leaves evenly serrate with many serrations; [widespread] |
............ ............ ..........18 Leaves with 3 (-5) teeth at the apex, otherwise entire |
............ ............ ..14 Plants in fruit (or sterile). |
............ ............ ............ 19 Leaflets entire, except for 3 (-5) teeth at the apex; [tribe Potentilleae] |
............ ............ ............ 19 Leaflets evenly serrate or crenate, each well-developed leaflet with > 7 teeth. |
............ ............ ............ ..20 Calyx lobes not subtended by bractlets. |
............ ............ ............ ....21 Fruit an aggregate of dry, non-adherent achenes; leaflets obtuse at apex; [tribe Colurieae] |
............ ............ ............ ....21 Fruit an aggregate of fleshy, adherent drupelets; leaflets acuminate at apex; [tribe Rubeae] |
............ ............ ............ ..20 Calyx lobes subtended by 5 sepaloid bractlets; [tribe Potentilleae]. |
............ ............ ............ ......22 Fruit an aggregate of dry achenes |
............ ............ ............ ......22 Fruit an accessory fruit of achenes borne on the surface of a fleshy, red receptacle. |
............ ............ ............ ........23 Fresh fruit reddish inside; leaflets serrate, 2.5-12 cm long; sepaloid bracts narrowing to apex, untoothed |
............ ............ ............ ........23 Fresh fruit whitish inside; leaflets crenate, 2-4 cm long; sepaloid bracts widest at apex, 3-5-toothed |
1 Ovary inferior; fruit indehiscent (pome). |
..2 Inflorescence a panicle, of > 25 flowers (6-40 in Pyracantha); leaves leathery, evergreen. |
....3 Plants armed with thorns |
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......4 Pomes purplish-black, 7-10 mm in diameter, each with 3-5 seeds; leaves mostly 10-30 cm long |
......4 Pomes orangey yellow, (10-) 20-30 mm in diameter, each with 1-2 seeds; leaves (2-) 4-10 cm long |
..2 Inflorescence an axillary or terminal raceme, fascicle, cyme, or umbel, of < 20 flowers; leaves herbaceous, deciduous. |
........5 Upper surface of leaves bearing dark glandular trichomes along the midrib (most easily seen with a 10× hand lens); shrubs |
........5 Upper surface of leaves lacking dark glandular trichomes along the midrib; shrubs and trees. |
..........6 Ovary and fruit 10-locular; inflorescence a raceme (rarely a fascicle); pome < 1 cm in diameter |
..........6 Ovary and fruit 5-locular; inflorescence a cyme, umbel, or fascicle (lacking an elongated central axis); pome 0.7-10 cm in diameter. |
............ 7 Styles distinct; exocarps (carpels within pericarp) bony and seedlike; trees and shrubs, with thorns |
............ 7 Styles usually connate at base; exocarps leather or papery and easily opened to expose seeds; small trees, unarmed, or armed with sharp spur branches. |
............ ..8 Pome globose to ovoid, lacking stone cells; anthers yellow to white; styles connate at the base; leaves blunt to acuminate; [apples and crabapples] |
............ ..8 Pome globose or pyriform, with stone cells; anthers reddish; styles distinct; leaves acute to acuminate; [pears] |
1 Ovary superior; fruit dehiscent (aggregate of follicles, or capsule) or indehiscent (drupe, aggregate of drupelets, aggregate of achenes). |
............ ....9 Leaves opposite; fruit an aggregate of usually 3-5 purple to black drupelets; [tribe Kerrieae] |
............ ....9 Leaves alternate; fruit various (see below; if an aggregate of drupelets, then with >5 drupelets). |
............ ......10 Leaves large, > 10 cm wide, palmately veined, palmately lobed; fruit an aggregate of drupelets; [tribe Rubeae] |
............ ......10 Leaves smaller, < 8 cm wide, pinnately veined, either not lobed or basally pinnately lobed; fruit a drupe, a capsule, an aggregate of follicles, or an aggregate of achenes. |
............ ........11 Leaves singly serrate or entire (rarely, as in Prunus americana, irregularly and slightly doubly serrate), not lobed basally. |
............ ..........12 Gynoecium of separate carpels; fruit an aggregate of follicles; [tribe Spiraeeae] |
............ ..........12 Gynoecium of fused carpels; fruit either a fleshy drupe or a capsule. |
............ ............ 13 Ovary 5-angled in ×-section; fruit a 5-angled capsule; leaves obovate, obviously broadest towards the tip; [tribe Osmaronieae] |
............ ............ 13 Ovary circular in ×-section; fruit a fleshy spherical drupe; leaves generally broadest near or below the middle; [tribe Amygdaleae] |
............ ........11 Leaves doubly serrate, also often lobed towards the base. |
............ ............ ..14 Corolla yellow; stems arching, green; fruit an aggregate of drupe-like achenes (dry and indehiscent); [tribe Kerrieae] |
............ ............ ..14 Corolla white to pink or rose; stems not both arching and green; fruit various (see below). |
............ ............ ....15 Inflorescence a dense, umbel-like corymb; leaf apices rounded to acute; fruit an aggregate of 5 follicles; [tribe Neillieae] |
............ ............ ....15 Inflorescence a raceme or a leafy panicle; leaf apices acuminate. |
............ ............ ......16 Fruit a single follicle; [exotic, planted, and rarely naturalized, as in e. VA]; [tribe Neillieae] |
............ ............ ......16 Fruit an aggregate of 2-4 drupe-like achenes; [rare native of calcareous habitats in sc. TN, nw. GA, n. AL, and disjunct westward in AR and MO]; [tribe Kerrieae] |
1 Leaflets < 5 mm wide, entire; densely-branched shrub to 1 m tall; flowers yellow; [tribe Potentilleae] |
1 Leaflets > 10 mm wide, serrate or crenate; shrubs, trees, or woody vines (see below); flowers white, pink, or purplish (rarely yellow in Rosa). |
..2 Leaves 1-pinnately compound, generally with > 11 leaflets; inflorescence a terminal panicle or corymb with numerous (> 100) flowers, the petals white and < 4 mm long; fruit a pome or follicle; upright tree or shrub with unarmed stems. |
....3 Inflorescence a panicle; fruit a follicle; shrub, to 2 m tall; [tribe Sorbarieae] |
....3 Inflorescence a corymb; fruit a pome; tree, generally > 2 m tall; [tribe Pyreae] |
..2 Leaves palmately or 1-pinnately compound, generally with < 11 leaflets; inflorescences axillary or terminal panicles or corymbs with few (<15) flowers, the petals white, pink, or purplish (rarely yellow) and > 6 mm long; fruit a hip or aggregate of drupelets; arching or upright shrubs or climbing or sprawling woody vines, the stems usually armed with prickles. |
......4 Fruit a hip, developing from a globose to urceolate hypanthium, enclosing the ovaries and achenes, except for the apical orifice; leaflets usually acute to obtuse at the apex; leaflet margins crenulate or serrulate; [tribe Roseae] |
......4 Fruit an aggregate of drupelets, developing from a flattish or hemispheric hypanthium, with the ovaries and drupelets exposed; leaflets usually acuminate at the apex; leaflet margins serrate or doubly serrate; [tribe Rubeae] |
