Ericaceae
Shrubs and shrublets, less commonly trees, usually evergreen. Lvs exstipulate, usually alternate, sometimes opposite or whorled. Infl. a terminal or axillary raceme, umbel or panicle, sometimes fls solitary. Fls ⚥, regular or nearly so. Calyx 4-5-lobed, persistent and sometimes accrescent. Corolla usually gamopetalous, 4-5-lobed, rarely petals free. Stamens usually twice as many as, sometimes as many as corolla lobes, usually inserted on or between the lobes of a fleshy hypogynous disc; filaments free or rarely ± connate; anthers 2-locular, dehiscing by terminal pores or short slits, sometimes with awns or tails; pollen shed in tetrads. Ovary usually superior, sometimes inferior, 2-5-(10)-celled; ovules numerous on axile placentae. Style and stigma single; stigma simple or lobed. Fr. a capsule or berry. Seeds usually numerous, occasionally few, very small.
SYNOPSIS
The synopsis is based on that of Stevens, P. F., Bot. J. Linn. Soc. 64: 1-53 (1971).
- A. Subfam. ERICOIDEAE.
- Habit ericoid. Winter buds minute; scales 0. Corolla very variable, always gamopetalous, persistent. Stamens as many as or twice as many as petals, dehiscing by terminal pores or terminal slits; awns flattened or 0. Capsule usually loculicidal, rarely septifragal.
- 1 Trib.
- Shrub with small, decussate, sessile scale lvs. Fls axillary, usually solitary, 4-merous. Calyx petaloid, always > corolla. Corolla deeply lobed, persistent. Capsule septifragal:
- Calluna
- 2. Trib. ERICEAE.
- Shrubs with small, usually whorled, petiolate scale lvs. Calyx usually herbaceous (not petaloid), < corolla. Corolla not deeply lobed, deciduous or persistent. Capsule loculicidal:
- Erica
- B. Subfam. RHODODENROIDEAE.
- Habit not ericoid. Winter buds prominent, scaly. Corolla gamopetalous, much more rarely choripetalous, usually opening widely. Stamens 5-14-(22), dehiscing by terminal pores, or by terminal or longitudinal slits; awns 0. Capsule usually septicidal, rarely septifragal.
- 3. Trib. DABOECIEAE.
- Lvs small. Infl. terminal, racemose, few-flowered, lacking scales. Corolla urceolate; lobes small. Stamens usually 8. Seeds ovoid:
- Daboecia
- 4. Trib. PHYLLODOCEAE.
- Lvs usually small. Infl. usually terminal, lacking scales. Corolla actinomorphic, rotate to urceolate. Stamens 5-10. Seeds small, ovoid:
- Kalmia L.
- 5. Trib. RHODOREAE.
- Lvs often large. Infl. usually terminal, with scales. Corolla actinomorphic to somewhat zygomorphic, very variable in shape. Stamens 5-15. Seeds variously shaped, winged:
- Rhododendron
- C. Subfam. VACCINIOIDEAE
- . Habit variable. Winter buds prominent, scaly. Corolla nearly always gamopetalous, usually urceolate or tubular. Stamens 5-12, dehiscing by apical pores or short slits; appendages present. Fr. a berry, drupe or loculicidal capsule.
- 6. Trib. ANDROMEDEAE.
- Shrubs, usually evergreen; lvs entire or serrulate. Infl. usually axillary. Corolla usually urceolate or tubular. Anthers with paired appendages, dehiscing by long terminal tubules. Ovary superior but sometimes tightly invested by fleshy calyx at fruiting. Capsule loculicidal, sometimes calyx fleshy and fr. berry-like, rarely a true berry:
- GaultheriaLeucothoe D.Don PernettyaPieris D. Don Zenobia D. Don
- 7. Trib. ARBUTEAE.
- Evergreen trees and shrubs. Lvs often large, nearly always alternate. Infl. usually of terminal racemes or panicles, usually lacking scales. Corolla urceolate. Filaments usually swollen at base. Ovary superior. Fr. a berry or drupe:
- ArbutusArctostaphylos Adans.
- 8. Trib. CASSIOPEAE.
- Small evergreen shrublets. Lvs small and scale-like. Fls solitary, terminal or axillary. Corolla ± campanulate, lobed to 1/4-⅔. Anthers dehiscing by broad apical slits. Ovary superior. Capsule loculicidal:
- Cassiope D.Don
- 9. Trib. ENKIANTHEAE.
- Deciduous or evergreen shrubs. Lvs serrate. Infl. terminal, umbellate or corymbose, with scales. Corolla urceolate or campanulate. Anthers dehiscing by long slits. Ovary superior. Capsule loculicidal:
- Enkianthus Lour.
- 10. Trib. VACCINIEAE.
- Shrubs, evergreen, or sometimes deciduous. Infl. usually axillary, racemose, fasciculate, or fls solitary; scales present or 0. Corolla usually tubular or urceolate, sometimes winged. Anthers usually dehiscing by tubules, with (1)-2 awns. Ovary inferior. Fr. a berry or drupe:
- Agapetes G. Don Cavendishia Lindley Vaccinicum
Key
c. 80 genera, 1500-2000 spp., temperate regions and especially montane tropical and subtropical areas.
A very large number of ericaceous plants are cultivated in N.Z., particularly South African Erica spp. and Sino-Himalayan and Japanese spp. and hybrids of Rhododendron. However, very few have become naturalised. The synopsis includes some genera common in cultivation but not naturalised.
The term "ericoid" is often applied to habit or lvs in this and other families which have small, crowded, ± narrowly linear lvs, as in many Erica spp.
