Seeds of South Australia
Baumea acuta (Cyperaceae)
Pale Twig-sedge
List of species for Baumea
Click on an image to enlarge it
Seed collecting:
December to April
Herbarium regions:
Southern Lofty, Kangaroo Island, South Eastern
NRM regions:
Adelaide and Mount Lofty Ranges, Kangaroo Island, South East
IBRA regions
Mount Gambier (SVP02)Southern Volcanic Plain
 Least Concern
Glenelg Plain (NCP02)Naracoorte Coastal Plain
 Least Concern
Lucindale (NCP03) 
 Near Threatened
Kangaroo Island (KAN01)Kanmantoo
 Rare   (IUCN: RA d(ii))   [mostly on roadsides; very specific to drainage lines]
Fleurieu (KAN02) 
 Rare   (IUCN: RA d(ii))   (Probable Decline)   [quality of habitat has declined]
Mount Lofty Ranges (FLB01)Flinders Lofty Block
 Vulnerable   (IUCN: VU B2ab(i,ii,iii))   (Probable Decline)   [quality of habitat has declined]
Lowan Mallee (MDD04)Murray Darling Depression
 Vulnerable   (IUCN: VU D2)   [very isolated]
RSCA map:
Regional Species Conservation Assessments per IBRA subregion. Please click the thumbnail map.
AVH map:
Australian distribution map (external link)
SA Census:
Census of South Australian plants (external link)     [genus Baumea]
Name derivation:
Baumea named after Antoine Baume (1728–1804), a French chemist and inventor. Acuta from the Latin 'acutus' meaning sharp or pointed.
Distribution:
Found on Kangaroo Island, southern Mount Lofty Ranges and the lower South-east in South Australia, growing in swamps and damp heath on open sandy soils. Also found in Western Australia, Queensland, New South Wales, Victoria and Tasmania.
Status:
Native. Uncommon in South Australia. Uncommon in Queensland. Common in all the other states.
Plant description:
Slender, tufted perennial sedge with long rhizome. Culms rigid, flat to biconvex, nodeless, smooth, to 35 cm high and 1.5 mm diameter. Leaves basal with flat to biconvex blade, sheath straw-coloured to pale red-brown, dull. Inflorescence oblong in outline, narrow, erect, to 14 cm long and 1 cm diameter. Spikelets few, 1-flowered, 4.5–6 mm long. Glumes 3 or 4, acute, red-brown, with margins ciliate or glabrous. Flowering betwen spring and summer.
Fruit type:
Short red brown heads at the tip of stems.
Seed type:
Dark red to black, ovoid to ellipsoid nut to 3 mm long and 2 mm wide, smooth and shiny surface.
Embryo type:
Capitate.
Seed collecting:
Collect whole heads that are brown, containing dark hard seeds. Not all heads will contain seeds.
Seed cleaning:
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.
Seed viability:
From two collections, the seed viability were high, at 100%.
Seed germination:
This species is generally difficult to germinate, it has morphophysiological dormancy and complex germination requirements.
Seeds stored:
LocationNo. of seeds
(weight grams)
Number
of plants
Date
collected
Collection number
Collection location
Date
stored
% ViabilityStorage
temperature
BGA 
MSB
6700 (10.5 g)
6700 (10.5 g)
100+11-Apr-2006DJD456
South Eastern
28-Jul-2006100%+5°C, -18°C
BGA3300 (5.4 g)200+4-Apr-2007DJD787
South Eastern
1-Aug-2007100%+5°C, -18°C
Location: BGA — the seeds are stored at the Adelaide Botanic Gardens, MSB — the seeds are stored at the Millennium Seed Bank, Kew, England.
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.