Tamaricaceae

This is a small, Old World family distributed in warm, dry regions from the Mediterranean and Africa to Central Asia. In Australia, one species of Tamarix is widely planted in dry areas as a drought-tolerant tree. It has naturalised and is becoming a serious weed on the Finke River in Central Australia.

Characteristic features of the family Tamaricaceae in Australia include:

• grey-green trees with fine, weeping branchlets and tiny, scale-like, alternate leaves ±clasping the stems
  
• flowers small, pink, in spikes or slender racemes terminating the branchlets, with 5 sepals, petals and stamens and a nectary-disc between the stamens
  
• ovary superior, developing into a small capsule; seeds with a coma of long, soft hairs

Description

Evergreen trees or shrubs. Leaves sometimes ±absent. Internal secretions not obvious. Plants glabrous. Leaves small or much reduced (i.e. to scales, etc.), alternate and spiral, sessile. Stipules absent. Lamina simple, symmetric, lanceolate or ovate; margins entire, involute or incurved; one-veined, with the midrib conspicuous, and the tertiary venation not reticulate; surfaces not punctate; herbaceous, membranous or papery. All the flowers bisexual. Inflorescences terminal or axillary, consisting of spikes. Bracts present. Pollination by wind. Flowers sessile. Floral disc present; nectaries present on the disc. Perianth regular, of 2 dissimilar whorls, imbricate in bud. Calyx segments free, of 5 sepals, herbaceous or papery. Corolla segments free, of 5 petals, alternating with the sepals, cream or pink, without contrasting markings, membranous or papery; claws absent; lobes ±entire. Fertile stamens 5 or 10 or more, opposite to, or not clearly correlated with, the sepals, free of the corolla, free of the ovary and style, distinct from each other, all ±equal. Anthers dorsifixed, versatile, opening outwards or inwards by longitudinal slits, 2-celled; appendages apical. Ovary superior and sessile. Carpels 3–4, fused; ovary with 1 locule. Style terminal, branching from the base. Ovules 2–numerous, stalked or apparently sessile; placentation basal or parietal. Fruit a dry, dehiscent, loculicidal capsule; the perianth on the maturing fruit deciduous or dry and persistent. Disseminule macro-surface with straight hairs; micro-surface ±smooth or striate, brown, dull. Seeds 2–numerous per fruit. Aril absent. Cotyledons 2. Embryo straight.

(Note: this description has been generated from the coded data compiled for the key. Any errors in the key data will be reflected in the descriptions.)

A treatment of the family Tamaricaceae has been published in:
Flora of Australia 8: 110-112.

Australian genera of Tamaricaceae (as recognised for the Flora of Australia)

* = all species introduced

*Tamarix