Xanthorrhoea from the Greek 'xanthos' meaning yellow and 'rheo' meaning to flow; referring to the yellow resin that is often produced from the leaves. Semiplana from the Latin 'semi' meaning half and the Greek 'planatus' meaning flat; referring to the leaves which can be flatted on one side.
Distribution and status
Found mainly in the southern Mount Lofty Ranges in South Australia, with scattered occurs on the Eyre Peninsula and in the South-east, growing in sandy soil woodland and heathland. Also found in Victoria. Native. Common in South Australia. Uncommon in Victoria.
Herbarium regions: Eyre Peninsula, Murray, Yorke Peninsula, Southern Lofty, South Eastern
NRM regions: Adelaide and Mount Lofty Ranges, Eyre Peninsula, Kangaroo Island, South Australian Murray-Darling Basin, South East
AVH map: SA distribution map (external link)
Trunkless shrub to 1 m tall with 1 to many crowns. Leaves transversely narrow-rhombic to very depressed-cuneate in section, to 12 mm wide and 3.5 mm thick, bluish-green, very glaucous. Inflorescence 200-375 cm long, scape 75-200 cm long, 15-30 mm diameter, spike 65-250 cm long, 25-45 mm diameter. with numerous creamy flowers. Flowering between October and November. This subspecies defer from the other subspecies found in South Australia, Xanthorrhoea semiplana ssp. tateana, which have trunks and a much longer and fatter flower spike (inflorescence 180-360 cm long; scape 40-125 cm long, 25-60 mm diameter, spike 140-300 cm long, 25-90 mm diameter Fruits are numerous woody capsules maturing to dark brown along the spike. Capsule split into three segments, each containing one black seed. Seeds are flat pyramid-like black seed to 10 mm long and 6 mm wide. Seed embryo type is linear under-developed.
Seed collection and propagation
Collect seeds between January and April. Cut off fruit spikes that have mature capsules, usually turning dark brown or beginning to split. The seeds inside should be black. Place the fruit spikes in a tray or bucket and leave to dry for 3-4 weeks or until most of the capsules split. Then shake the fruit spike in a bucket to dislodge the seeds. Store the seeds with a desiccant such as dried silica beads or dry rice, in an air tight container in a cool and dry place. From one collection, the seed viability was high, at 100%. Seeds are non-dormant, viable seed should germinate readily without any treatment.