SIMAROUBACEAE

QUASSIA or SIMAROUBA FAMILY

Elizabeth McClintock

Shrub, tree, generally dioecious
Stem often thorny; bark often bitter
Leaves generally alternate, simple, entire, or pinnately compound with subentire leaflets
Inflorescence: panicle, raceme, or flowers solitary
Flower inconspicuous; sepals generally 5, generally fused at base, generally erect; petals generally 5, free, generally spreading; stamens generally 10–15, generally inserted on a disk, filaments often with a basal scale; pistils generally 2–5, ovaries superior, 1-ovuled (if pistil 1, chambers generally 2–5, 1-ovuled), styles free or partly fused
Fruit: winged achene, drupe, berry, or capsule
Genera in family: ± 25 genera, ± 150 species: tropical, warm temp; some cultivated
Reference: [Brizicky 1962 J Arnold Arbor 43:173–186]
Bark, leaves used in medicine.

AILANTHUS

Tree, unarmed, ± dioecious, with a few bisexual flowers
Leaves deciduous, generally ± odd-pinnate, ill-smelling when crushed
Inflorescence: large panicle, terminal
Flower: calyx lobes 5–6; petals 5–6; stamens 10–12; ovaries very compressed, adherent near middle, styles ± free but twisted around one another
Fruit: winged achene, 2–5 per flower, ± pendent
Species in genus: ± 15 species: eastern Asia, ne Australia
Etymology: (Moluccan: sky tree)

Introduced

A. altissima (Mill.) Swingle

TREE OF HEAVEN

Plant < 20 m, rapidly growing; young parts ± glandular-puberulent
Leaf 3–9 dm; leaflets 13–25, 8–13 cm, lanceolate, base generally ± truncate, with 2–4 teeth, each with a large gland on lower surface
Inflorescence 10–20 cm
Fruit < 5 cm, linear or oblong, seed near middle
Ecology: Common. Disturbed urban areas, waste places
Elevation: < 1250 m.
Bioregional distribution: California Floristic Province
Distribution outside California: native to e Asia
Cult as street tree, spreading by seeds, invasive roots. Common near old Chinese habitations, especially SNF.