Rosaceae
Herbs, shrubs or trees, mostly perennial, sometimes armed. Lvs usually alternate, sometimes in basal rosettes, often toothed or lobed or compound; stipules usually present, sometimes adnate to petiole. Fls solitary or in a cyme, corymb, raceme or umbel, regular, 4-5-(6)-merous, perigynous or epigynous, sometimes intermediate, usually ⚥. Receptacle forming a flat, concave or tubular hypanthium (often called a calyx tube) bearing sepals, petals and stamens on the outer or upper margin. Epicalyx often present. Sepals free or partly adnate to ovary. Petals as many as sepals, rarely 0, imbricate. Stamens numerous, rarely reduced to 1-2; filaments usually free; anthers 2-locular, dehiscing longitudinally. Ovary superior or inferior, sometimes 1/2 inferior, with 1-several locules; carpels 1 or more, free or connate, often ± adnate to calyx tube; styles free or connate; ovules 2, rarely 1 or several in each carpel, pendulous, superposed. Fr. of 1 or more achenes, drupes, pomes, follicles, or rarely capsules, the hypanthium sometimes coloured and fleshy; seeds usually lacking endosperm.
SYNOPSIS
The synopsis is based on that of Rehder, A., Manual of Cultivated Trees and Shrubs hardy in North America (1947).
- A. Subfam. MALOIDEAE.
- Armed or unarmed trees or shrubs; lvs usually simple, sometimes pinnate; stipules present; fls small to medium-sized; hypanthium deeply campanulate or cup-shaped, closed at apex, adnate to receptacle; epicalyx 0; ovary inferior; carpels 2-5, ± connate; fr. with fleshy receptacle; carpel walls leathery or papery (a pome) or bony; seeds usually 2 per carpel.
- 1. Trib. CRATAEGEAE.
- Carpel walls woody at maturity. Fr. containing 1-5 bony nutlets:
- CotoneasterCrataegusMespilus L. Pyracantha
- 2. Trib. MALEAE.
- Carpels with leathery or papery walls at maturity. Fr. a pome, 1-5-celled, each cell containing 1-2 seeds:
- AmelanchierChaenomelesCydoniaEriobotryaMalusPhotinia Lindley PyrusRhaphiolepisSorbusStranvaesia
- B. Subfam. PRUNOIDEAE.
- Armed or unarmed shrubs or trees; lvs simple; stipules present; fls usually of medium size; hypanthium deeply cup-shaped; epicalyx 0; ovary superior; carpels 1-(5); fr. a drupe; seed 1 per carpel.
- 3. Trib. PRUNEAE:
- C. Subfam. ROSOIDEAE.
- Armed or unarmed shrubs, or herbs, rarely small trees; lvs mostly compound, sometimes simple; stipules usually present; fls small to large; hypanthium flat to conic or deeply urceolate; epicalyx often present; ovary superior or inferior; carpels free, usually many and often clustered on a carpophore; fr. of achenes sometimes embedded in a fleshy receptacle, or drupelets, always indehiscent; seeds 1-2 per carpel.
- 4. Trib. DRYADEAE.
- Perennial unarmed herbs or shrubs; lvs simple and entire, or lobed to pinnatisect, pinnate or palmate, stipulate; epicalyx usually present, rarely 0; carpels 1-numerous, free, on a flat to conic receptacle, sometimes with a persistent hooked style at fruiting; head of usually dry, very rarely fleshy achenes exposed on receptacle or very rarely enclosed by calyx:
- Geum
- 5. Trib. POTENTILLEAE.
- Perennial unarmed herbs or sometimes shrubs; lvs usually pinnate, sometimes palmate or ternate, stipulate; epicalyx present or 0; carpels 1-numerous, free, on a convex to conic receptacle; fr. a head of achenes, sometimes these at least partly embedded in a swollen fleshy receptacle:
- DuchesneaFragariaPotentilla
- 6. Trib. POTERIEAE.
- Armed or unarmed shrubs, trees or perennial herbs, rarely annual; lvs simple and entire, or lobed to deeply divided, pinnate or palmate, stipulate; epicalyx usually present, sometimes 0; carpels 1-2-(4), free, sometimes with a persistent hooked style at fruiting; fr. of achenes enclosed in usually dry and often hard or rarely fleshy calyx:
- AcaenaAlchemillaAphanesSanguisorba
- 7. Trib. ROSEAE.
- Shrubs, usually prickly, often lianoid; lvs usually pinnate, very rarely simple, usually stipulate, very rarely exstipulate; epicalyx 0; carpels numerous, free, enclosed in a ± urceolate to globose receptacle; fr. a hip consisting of the large fleshy receptacle containing several to many bony achenes:
- Rosa
- 8. Trib. RUBIEAE.
- Shrubs, usually prickly and lianoid or with creeping stems; lvs usually palmate or pinnate, sometimes simple, stipulate; epicalyx 0; carpels few to many, free, on a convex receptacle; fr. usually a collection of fleshy drupelets, rarely dry:
- Rubus
- 9. ULMARIEAE.
- Perennial unarmed herbs; lvs pinnate, or palmately lobed, stipulate; epicalyx 0; carpels 5-15, free, in 1 whorl on a flat to convex receptacle; fr. a compact head of achenes:
- Filipendula
- D. Subfam. SPIRAEOIDEAE.
- Unarmed shrubs, sometimes herbs, rarely trees; lvs simple or compound; stipules present or 0; fls usually small; hypanthium saucer- or cup-shaped; epicalyx 0; ovary superior; carpels usually 5, free or connate; fr. of 1-5 follicles, rarely achenial. Seeds several per follicle.
- 10. Trib. GILLENIEAE.
- Shrubs, subshrubs, occasionally small trees or perennial herbs; lvs imparipinnate, occasionally 3-foliolate, stipulate; ovules 2-8; carpels 2-5, partly free, opening by ventral suture only; seeds wingless:
- Sorbaria
- 11. Trib. NEILLIEAE.
- Shrubs; lvs simple, usually lobed, stipulate; ovules > 10; carpels 1-5, slightly united at base, opening by dorsal and ventral sutures or by ventral suture only; seed wingless:
- Physocarpus
- 12. Trib. QUILLAJEAE.
- Shrubs or small to medium-sized trees; lvs simple; stipules present or 0; ovules 2; carpels (2)-5, free or united, opening by ventral suture; seed winged or apiculate:
- Exochorda
- 13. Trib. SPIRAEAE.
- Shrubs or subshrubs with simple lvs or sometimes perennial herbs with compound lvs; stipules 0; ovules (2)-10; carpels (2)-5-(8), free or almost so, opening by ventral suture and dorsally at the top; seed wingless:
- Spiraea
Key
c. 120 genera, c. 3500 spp., worldwide, most numerous in N. temperate regions.
For this family authorship is indicated for each genus.
The family, as defined here, includes many large and important genera and introduced members are often abundant and conspicuous both as naturalised and cultivated plants. Many spp. long persist as relics of cultivation, and in and around old settlements throughout N.Z. members of the Rosaceae are almost always prominent.
Many genera are economically important with most of the fruit trees of temperate regions belonging to this family. Hundreds of spp. and cvs are grown as ornamentals, particularly in the genera Rosa, Prunus, Crataegus, Cotoneaster, Spiraea, Malus and Sorbus. Some members of the family are serious agricultural weeds, especially spp. of the Rubus fruticosus agg.
The family can be divided into 5 clear-cut subfamilies; the 4 which are wild in N.Z. are Spiraeoideae, Rosoideae and Prunoideae (with basic chromosome numbers of 7, 8 or 9), and Maloideae (with a basic chromosome number of 17). The other subfamily does not occur in N.Z. Frs of Rosaceae are very diverse and provide important characters for subdividing the family. Fleshy frs mostly belong to the Maloideae (pomes), Prunoideae (drupes) and Rosoideae (aggregates of fleshy drupelets, or achenes with a fleshy receptacle).
The synopsis below includes 3 genera not known to be truly wild in N.Z., 2 of which are very common in cultivation and long persist in abandoned gardens. Kerria japonica (L.) DC. is a deciduous shrub with erect green stems and single or double yellow fls which often forms suckering thickets. Few settled parts of N.Z. are without individual plants or hedges of the evergreen Photinia glabra (Thunb.) Maxim. and its hybrid cvs, which are mainly grown for the rather large glossy lvs which change from shades of red to dark green as they mature. The panicles of small white fls are rarely followed by the small black berries in N.Z. Mespilus germanica L., medlar, is only seen as a rather uncommon relic of cultivation. It is a small, deciduous tree with large, solitary, white fls and a large, brown, depressed-globose pome-like fr.
