(from its native name Ailanlo, meaning Tree of Heaven). Simaroubaceae. Large trees: leaves. alternate, large, pinnate, deciduous: flowers. small. in large terminal panicles, polygamous; petals 5; stamens 10; flower. consisting of 1-5 distinct samaras. Five species in Central and S. Asia and N. Australia—Large. ornamental trees of loose and somewhat spreading habit, with elegant, feathery foliage. Very rapid growers. Good for smoky cities. Suckers from the roots. Propagated by seeds and root cuttings.