Acacia carneorum
Acacia carneorum, also referred to as purple-wood wattle, needle wattle, dead finish or by its former scientific name, Acacia carnei, is a plant species in the genus Acacia. It occurs in small populations in far north-west New South Wales and South Australia. Purple-wood wattle is a threatened shrub, listed as vulnerable under the Environmental Protection and Biodiversity Conservation Act (EPBC Act), NSW Threatened Species Conservation Act 1995 and South Australia National Parks and Wildlife Act 1992. Description The wattle is distinctly known for its deep-purple heartwood. However, once cut and left exposed to air for a few weeks, the purple turns near black. From the exterior, the wattle is a dark green, prickly shrub to small tree that can grow 2–4 m high and up to 8m wide. The growth rate is very slow in mature plants, shown through photo points of over 30 years. The prickly appearance of the shrub refers to the pointy phyllodes (leaves), which are rigid, straight, 4 angled and linear in shape. Furthermore, the leaves are approximately 2–9 cm long and 1-2mm wide, subglaucous (between glaucous and green) with lighter coloured veins at each angle and hairless with age. The flowers are bright yellow, fuzzy spheres, 7-10mm in diameter that come singularly or rarely in pairs and are located on 12-25mm hairy stalks in the axil of phyllodes. The pods are 3–5 cm long and 10mm wide, straight or slightly curved and made of a hard and woody material covered in little, soft, white hairs with slight constrictions between seeds. Carbon dating has found that these plants range from approximately 120–330 years of age and this research also found that populations are heavily skewed towards older plants, meaning there has been little or no replacement in these populations since the introduction of grazing animals in the 1860s. This however is not the only reason for small populations. The plant has an ancient history of asexual reproduction along with habitat disturbance which both have affected the setting of seed. Reproduction Inflorescences display a short protogynous phase (female organs mature first) and the majority are simultaneously hermaphroditic (bi-sexual). Most species of Acacia are at least partially self-incompatible but this is not known with purple-wood wattle. The fruits are orange, woody arils and may remain on the parent for several years after splitting open. Fruit production is very rare. Studies from 2010 to 2012 show that most populations continue to produce no fruit. There is rarely pod and seed production in these plants and the setting of viable seed is rare. Successful reproduction is very limited, only two study sites represent known seed sources in NSW. Majority of reproduction is clonal. Root suckers are produced twice a year during autumn and spring growth. Purple wood wattle's dominant reproductive mode is clonal. Clonal reproduction is favoured in situations where the trade-off between survival and seed production favours survival or if disturbance is preventing flowering and fruiting. Clonality can result in permanent failure of sexual reproduction. It can also result