Juncus flavidus

Description

Juncus australis is a species of rush known by the common names austral rush, leafless rush and wīwī. The species is native to south-eastern Australia and New Zealand, where it can be found around bodies of water. Its habitat is wet or seasonally wet grasslands and woodlands, and it can grow in dense and damp soil along rivers and creeks. It is a rhizomatous perennial rush that grows up to 120 centimetres tall. The plant flowers in clusters, with dense heads at the tip of the stem. Juncus australis grows predominantly in circular clumps, loosely packed and growing in an open habit. The clumps are often formed around one or a few live or dead stems in the centre of the clump, and grow on average 50 centimetres from other clumps. The stems of the plant grow vertically, growing 60–120 cm high. The stems are tough and not easily squashed or broken. The colouration of the culm is relatively dull, with no shine, and ranging from green to blue-green or grey-green. The diameter of the culm ranges from 1.5 millimetres to 4 millimetres, with each stem having 30-60 striations, having a consistent distance between each striation. The pith is not solid throughout the culm, generally having large, non-continuous air pockets throughout the stem. The plant has no leaves, but most culms have several bracts, changing in colour from yellow to brown. The basal sheaths are shiny at the base, and range in colour between dark yellow-brown and chestnut brown. The inflorescence appears in a lateral formation, with “flowers clustered at the ends of stroud branchlet tips; sometimes condensed into a globose head”. The flowers grow to be 2.2 to 3 millimetres long, and with a light green colouration, that turns to light brown later in the plant’s cycle. The flower heads are branched and are formed around one or more dense clusters. The tepals of the flowers are straw-like and have a lightly coloured reddish-brown band, running longitudinally on either side of the stramineous midrib. The capsules are stramineous, with a golden-brown apex. The capsule length is typically 2 to 3 millimetres long, and is typically shorter than, or equal to the tepals, although in rare cases can exceed the tepals. The capsules are ovoid to obovoid, becoming obtuse and almost retuse as the apex of the capsule. The capsules are pale in colour, and are green to greenish brown.