NEW SOUTH WALES FLORA ONLINE

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Synonyms: Racosperma APNI*

Description: Trees or shrubs.

Immature leaves bipinnate, mature leaves bipinnate or reduced to terete or flat phyllodes; 1 or more glands often present on the leaf rachis or petiole or along the upper margin of the phyllode; the base of the petiole or phyllode is often distinctive and ± swollen and is called the pulvinus; stipules often caducous, occasionally spinescent.

Flowers small, in globose, ± ovoid or cylindrical heads in simple, racemose or sometimes paniculate inflorescences, the main axis sometimes grows out into a leafy shoot; separate male and bisexual flowers in each head. Sepals and petals 4 or 5, free or variously united. Stamens numerous, free, exserted, usually yellow. Style filiform, ± longer than the stamens.

Pods mostly leathery or cartilaginous, sometimes woody, flat to terete, usually dehiscent; seeds transverse to longitudinal in the pod; funicle often folded or expanded into a fleshy aril.

Illustration M. Flockton

Flower Photo J. Plaza

Herbarium Sheet

Herbarium Sheet

Distribution and occurrence: Widespread and abundant, especially in arid and semi-arid areas. World: >1500 spp., trop. to temp. regions of all continents except Eur., common in Afr. & Aust. Aust: c. 960 spp. (most spp. endemic except for c. 8 spp. native and c. 7 spp. exotic), all States (>235 spp. in N.S.W.).

Note: Glands on the rachis within 1 mm above and below the insertion of the pinnae are regarded as jugary glands. Glands on the rachis outside this region are regarded as interjugary glands. Basal pinnae are sometimes much reduced or lost (leaving small scars) giving the appearance of a longer petiole.

The following records of species occurring naturally in N.S.W. have not been substantiated: A. dietrichiana F. Muell. [A. juncifolia Benth. var. planifolia Benth.]; A. gnidium Benth.; A. longispicata Benth.; A. menzellii J.M. Black; A. nilotica (L.) Willd. ex Del.; A. prainii Maiden [A. prolifera J.M. Black]; A. resinicostata Pedley.

Many species are commonly cultivated as ornamentals; various species have been used for shade, shelter belts, hedges and fodder as they are fast-growing. A number of species are also the source of timber (e.g. A. melanoxylon); the bark of others are used for tannin, gum and dyes. Seeds are used in food, such as 'wattle seed ice cream' and 'wattle seed scones'.

Venation details. A, phyllode with numerous longitudinal veins, minor veins not anastomosing; B, minor veins anastomosing between longitudinal veins; C, minor veins anastomosing and forming a fine reticulum. Leaf types. A, phyllode with marginal gland adjacent to pulvinus and 3 equally prominent longitudinal veins; B, bipinnate leaf with 4 pairs of pinnae (each with 7 or 8 pairs of pinnules) and with glands along leaf rachis and on petiole. Inflorescence types. A, cylindrical flower head in axil of phyllode (dotted line indicates the inflorescence rachis); B, pair of globose flower heads on simple axillary peduncles; C, pair of globose flower heads on a short axillary axis; D, globose flower heads (5) in an axillary raceme. Flower, inflorescences and seeds. A, flower (with fused calyx, partly fused corolla, numerous stamens and style); B, globose head with 5 flowers (in bud); C, cylindrical head with scattered flowers (in bud); D–F, seeds with funicles; D, elongate funicle not expanded below seed; E, funicle folded and slightly expanded below seed; F, funicle folded and encircling seed, expanded into aril below seed.