Prior names
Baumea rubiginosa
Schoenus rubiginosus
Melancranis rubiginosa
Gahnia glomerata
Fuirena rubiginosa
Cladium rubiginosum
Cladium glomeratum
Common names
Soft Twig-sedge
Soft Twig-rush
Etymology
Machaerina from the Latin 'machaera' meaning a bent dagger or sword, and the feminine diminutive suffix '-ina", referring to the shape of the leaves of some species (formally Baumea named after Antoine Baume (1728 - 1804), a French chemist and inventor). Rubiginosa means rusty-reddish colour.
Distribution and status
Found on Kangaroo Island, Fleurieu Peninsula and the lower South-east in South Australia, growing in swamps and other damp areas, on sandy soil. Also found in all States. Native. Uncommon in South Australia. Common in the other States.
Herbarium regions: Southern Lofty, Kangaroo Island, South Eastern, Green Adelaide
NRM regions: Adelaide and Mount Lofty Ranges, Kangaroo Island, South East
AVH map: SA distribution map (external link)
Plant description
Perennial sedge with subterete or somewhat angled or compressed stems to 100 cm high, usually with 1 node above the base. Basal leaves rather wider than the stems, more or less compressed. Stem leaves with long sheaths and short channelled blades, all the blades pungent-pointed. Flowers in narrow, dense or interrupted zig-zag panicle with reddish or brown ovoid spikelets in erect clusters, crowded along the branches. Flowering between spring and summer. Fruits are long, dense golden-brown heads at the tip of stems. Seeds are red- brown ovoid nut to 3 mm long and 2 mm wide with shiny smooth surface. Seed embryo type is capitate.
Seed collection and propagation
Collect seeds between March and December. Collect whole heads that are brown, containing dark hard seeds. Not all heads will contain seeds. Place the heads in a tray and leave to dry for one to two weeks. Then rub the heads with a rubber bung to dislodge the seeds. Use a sieve to separate any unwanted material. 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. Not all mature-looking seeds are viable. Seed viability is variable depending on maturity of seeds when collected. This species is generally difficult to germinate, it has morphophysiological dormancy and complex germination requirements.
| Location | No. of seeds (weight grams) | Number of plants | Date collected | Collection number Collection location | Date stored | % Viability | Storage temperature |
|---|---|---|---|---|---|---|---|
| BGA | 1,200 (3.3 g) | 50+ | 5-Apr-2005 | DJD129 Southern Lofty | 28-Mar-2006 | 65% | -18°C |
| BGA MSB | 6,600 (18.25 g) 6,600 (18.25 g) | 50+ | 5-Apr-2005 | DJD131 Southern Lofty | 28-Mar-2006 | 80% | -18°C |
| BGA | 9,900 (18.348 g) | 27-Feb-2023 | JRG891 Southern Lofty | 20-Jun-2023 | 100% | -18°C, -80°C |
Number of plants: This is the number of plants from which the seeds were collected.
Collection location: The Herbarium of South Australia's region name.
% Viability: Percentage of filled healthy seeds determined by a cut test or x-ray.