ERICACEAE

HEATH FAMILY

Gary D. Wallace, except as specified

Perennial, shrub, tree
Stem: bark often peeling distinctively
Leaves simple, generally cauline, alternate, opposite, rarely whorled, evergreen or deciduous, often leathery, petioled or not; stipules 0
Inflorescence: raceme, panicle, cyme, or flowers solitary, generally bracted; pedicels often with 2 bractlets
Flower generally bisexual, generally radial; sepals generally 4–5, generally free; petals generally 4–5, free or fused; stamens 8–10, free, filaments rarely appendaged, anthers awned or not, dehiscent by pores or slits; nectary generally at ovary base, disk-like; ovary superior or inferior, chambers generally 1–5, placentas axile or parietal, ovules 1–many per chamber, style 1, stigma head- to funnel-like or lobed
Fruit: capsule, drupe, berry
Seeds generally many, sometimes winged
Genera in family: ± 100 genera, 3000 species: generally worldwide except deserts; some cultivated, especially Arbutus, Arctostaphylos, Rhododendron, Vaccinium
Reference: [Wallace 1975 Wasmann J Biol 33:1–88; 1975 Bot Not 128:286–298]
Subfamilies Monotropoideae, Pyroloideae, Vaccinioideae sometimes treated as families. Nongreen plants obtain nutrition from green plants through fungal intermediates.

ARCTOSTAPHYLOS

MANZANITA

Philip V. Wells

Shrubs, small trees
Stem prostrate to erect; fire-resistant burl sometimes present at base; bark generally reddish, smooth or gray, rough, and shredded; hairs generally alike on twig, inflorescence axis, bract
Leaves alternate, spreading to ascending, evergreen; blade surfaces generally alike, sometimes convex, differing in color (stomata restricted to lower surface) or hairiness; margin flat to rolled
Inflorescence: raceme or panicle-like, terminal; branches raceme-like; flowers bracted; bracts leaf-like, generally flat or scale-like, generally folded, keeled; immature inflorescence present late summer through winter
Flower radial; sepals generally 5, free, persistent; corolla generally 5-lobed, urn-shaped to ± spheric, white to pink; stamens generally 10, included, filament base glabrous or hairy, anther 2-pored, awns 2, recurved; ovary superior, base surrounded by nectary disk, chambers 2–10, ovule 1 per chamber, style 1, stigma head-like
Fruit: drupe, berry-like, generally ± spheric; pulp generally thick, mealy; stones 2–10, free, separable, or strongly fused
Species in genus: ± 60 species: North America (especially CA) to C.Am, Eurasia
Etymology: (Greek: bear berries)
Reference: [Wells 1988 Madroño 35:330–341]
Observation of hairs requires 10X magnification. Distribution of many species local; hybridization occurs in areas of overlap
Horticultural information: Beautiful but mostly DFCLT due to fungus and often salinity and alkali. Avoid overhead watering in hot weather. CVS are the easier garden subjects.

Native

A. columbiana Piper

Shrub, tree-like, 2–10 m; burl 0
Stem: twigs densely tomentose, generally with long, white bristles, gland-tipped or not
Leaves spreading; petiole 4–10 mm; blade 4–6 cm, 2–3 cm wide, generally ovate to elliptic, base wedge-shaped to ± rounded, margin entire, surfaces alike, dark green, dull, finely tomentose, ± sparsely glandular-bristly, papillate, becoming glabrous
Inflorescence ± open; branches 3–8; bracts 10–18 mm, leaf-like, oblong-lanceolate, acuminate; pedicel 2–4 mm, finely glandular-bristly; immature axes 15–25 mm, spreading, framed by large, stiff bracts
Flower: ovary densely white-hairy, sparsely glandular or not
Fruit 8–11 mm wide, sparsely hairy
Chromosomes: n=13
Ecology: Rocky slopes, coniferous forest
Elevation: < 800 m.
Bioregional distribution: North Coast, w Klamath Ranges, Outer North Coast Ranges
Distribution outside California: to British Columbia
Plants without long, white, gland-tipped hairs are called forma tracyi (Eastw.) P. Wells
Synonyms: var. t. (Eastw.) J.E. Adams
Hybrids with A. uva-ursi are called A. X media Greene.
Horticultural information: DRN, SUN: 4, 5, 17 &IRR: 7, 14, 15, 16; DFCLT.