CISTACEAE

ROCK-ROSE FAMILY

Elizabeth McClintock

Perennial, shrub; hairs short and in stellate clusters, or short or long and simple, peltate, or glandular
Stem erect, generally branched
Leaves simple, generally opposite, entire, petioled or not; stipules present or 0
Inflorescence: cyme (raceme- or panicle-like), or flowers solitary
Flower generally bisexual, radial; sepals 5, outer 2 often narrower, bract-like, or 3, often persistent in fruit; petals generally 5, generally ephemeral; stamens generally many, free, ± persistent in fruit or not; ovary superior, chamber 1 (or appearing as 3–10 from intruded parietal placentas), style 1 or 0, stigma generally 1, entire or 3–10-lobed
Fruit: capsule, loculicidal, 3–10-valved
Seeds 3–many
Genera in family: 8 genera, 165 species: warm temp, especially Medit; some cultivated (Cistus ; Helianthemum ; Tuberaria )
Reference: [Brizicky 1964 J Arnold Arbor 45:346–357]
Fls open in sunshine for < 1 day.

CISTUS

ROCK-ROSE

Shrub, evergreen, hairy
Stem < 2.5 m
Leaves generally opposite, ovate to oblong, petioled or not; stipules 0
Inflorescence panicle-like or flowers solitary
Flower: sepals 3 or 5; petals white or pink to purple, generally with dark or yellow blotch at base; ovary 1-chambered, placentas 5, style 1 or 0, stigma large, hemispheric, 5–10-lobed
Fruit 5–10-valved
Etymology: (Ancient Greek name)
Reference: [Bean 1970 Trees & shrubs Brit Isles I:615–629]
Some hybrids and cultivars.

Introduced

C. ladanifer L.

GUM CISTUS

Stem 1–2.5 m, shiny, resinous, sticky, with sessile glands
Leaf sessile, 4–8 cm, linear-lanceolate to narrow-oblong, generally with 3 main veins from base
Inflorescence: flowers solitary at ends of lateral branchlets
Flower: sepals 3; petals 3–5 cm, white, generally with red or yellow blotch at base; style short
Ecology: Uncommon. Disturbed places
Elevation: < 300 m.
Bioregional distribution: s Central Coast, San Gabriel Mountains
Distribution outside California: native to sw Europe
[sometimes mispelled ladaniferus]