Seeds of South Australia
Swainsona formosa (Leguminosae)
Sturts desert-pea
List of species for Swainsona
Display more images
Click on an image to enlarge it
Seed collecting:
September to February
Herbarium regions:
North Western, Lake Eyre, Nullarbor, Gairdner-Torrens, Flinders Ranges, Eastern, Eyre Peninsula, Northern Lofty
NRM regions:
Alinytjara Wilurara, Northern and Yorke, South Australian Arid Lands
IBRA regions
SUMMARY
Olary Spur (FLB03)Flinders Lofty Block
 Rare   (IUCN: RA d(i))   (Probable Decline)
Northern Flinders (FLB05) 
 Least Concern
Central Flinders (FLB06) 
 Near Threatened
Myall Plains (GAW01)Gawler
 Rare   (IUCN: RA d(ii))   (Probable Decline)   [rainfall dependent]
Gawler Volcanics (GAW02) 
 Least Concern   (Probable Decline)
Gawler Lakes (GAW03) 
 Least Concern   (Probable Decline)
Arcoona Plateau (GAW04) 
 Least Concern   (Probable Decline)
Kingoonya (GAW05) 
 Least Concern   (Probable Decline)
Torrens (GAW06) 
 Least Concern
Roxby (GAW07) 
 Least Concern
Commonwealth Hill (GAW08) 
 Least Concern
Maralinga (GVD03)Great Victoria Desert
 Least Concern
Yellabinna (GVD06) 
 Rare   (IUCN: RA d(ii))   [rainfall dependent]
Carlisle (NUL01)Nullarbor
 Least Concern
Nullarbor Plain (NUL02) 
 Least Concern
Barrier Range Outwash (BHC04)Broken Hill Complex
 Rare   (IUCN: RA d(i))   (Probable Decline)
Bimbowrie (BHC05) 
 Rare   (IUCN: RA d(i))   (Probable Decline)
Curnamona (BHC06) 
 Rare   (IUCN: RA d(i))   (Probable Decline)
Breakaways (STP01)Stony Plains
 Near Threatened
Oodnadatta (STP02) 
 Near Threatened
Murnpeowie (STP03) 
 Near Threatened
Peake-Dennison Inlier (STP04) 
 Near Threatened
Witjira (STP06) 
 Rare   (IUCN: RA d(ii))
Everard Block (CER03)Central Ranges
 Near Threatened
Tieyon (FIN03)Finke
 Rare   (IUCN: RA d(ii))   (Probable Decline)
Pedirka (FIN04) 
 Least Concern
IBRA regions
DISPLAY ALL
3 of 6 subregionsFlinders Lofty BlockLeast Concern
, Near Threatened
, Rare
8 of 8 subregionsGawlerLeast Concern
, Rare
2 of 4 subregionsGreat Victoria DesertLeast Concern
, Rare
2 of 3 subregionsNullarborLeast Concern
3 of 4 subregionsBroken Hill ComplexRare
5 of 7 subregionsStony PlainsNear Threatened
, Rare
Everard Block (CER03)Central RangesNear Threatened
2 of 2 subregionsFinkeLeast Concern
, Rare
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 Swainsona]
Name derivation:
Swainsona named after Isaac Swainson (1746-1812, an English scientist and horticulturalist who had a private botanic garden near London. Formosa is Latin for beautiful.
Distribution:
Found scattered across the mid and upper part of South Australia. Also found in Western Australia, Northern Territory, Queensland and New South Wales.
Status:
Native. Common in South Australia. Common in other states.
Plant description:
Prostrate annual or bi-annual herb, spreading to 2m or more with hairy stems and leaves making the plant appear grey-green. Flowers are bright red and large with a black dot (boss) in the centre, on an erect stem.
Fruit type:
Large hairy grey pods with numerous seeds inside.
Seed type:
Small brown, some with black spots, reniform seeds to 5mm long with a wrinkled surface.
Embryo type:
Bent.
Seed collecting:
Collect mature pods. Mature pods can be found lying on the ground next to the plant containing hard seeds.
Seed cleaning:
Place the pods in a tray and leave to dry for a week. When dried the pods can become hard and difficult to open. Use a rubber bung to rub the pods or break the pods open with your fingers to dislodge the seeds. Use a sieve to separate the 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, ranging from 90% to 100%.
Seed germination:
This species has physical dormancy that need to be overcome for the seed to germinate (e.g. nicking or softening the seed coat).
Seeds stored:
LocationNo. of seeds
(weight grams)
Number
of plants
Date
collected
Collection number
Collection location
Date
stored
% ViabilityStorage
temperature
BGA 
MSB
15500 (100 g)
8500 (55.59 g)
100+3-Nov-2009DJD1584
Eyre Peninsula
Jun-201090%-18°C
BGA3000 (25.69 g)1223-Nov-2010KHB531
Flinders Ranges
1-Jan-2012100%-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.
Germination table:
DateResultT0T50Pre-treatment | Germination medium | Incubator: Photoperiod / Thermoperiod
April 2010100%3d3d Seed coat nicked.
1% water agar.
Incubated under spring/autumn conditions
September 1992100%1d1d Seed coat nicked.
Wet filter paper placed over vermiculite.
16 hours.  /  23°C (24hrs).
September 199295%1d1d Submerged in boiled water until cooled.
Wet filter paper placed over vermiculite.
16 hours.  /  23°C (24hrs).
September 199265%1d7d Submerged in boiling water for 5secs.
Wet filter paper placed over vermiculite.
16 hours.  /  23°C (24hrs).
September 199250%1d13d Submerged in boiling water for 10secs.
Wet filter paper placed over vermiculite.
16 hours.  /  23°C (24hrs).
Result: Maximum percentage of germination observed.
T0: Number of days before first germinant observed.
T50: Number of days to achieve 50% germination.
Pre-treatment: The initial treatment that the seeds received prior to placement on germination media.
Germination medium: The substrate that seeds were placed on for the duration of the germination experiment.
Incubator conditions:
Photoperiod: The duration of light exposure that the seeds were subject to during a 24 hour period.
Thermoperiod: The constant or diurnal temperatures that seeds were subject to during a 24 hour period.
Winter conditions: 15°C 20 h (3am→11pm); 5°C 4 h (11pm→3am) / 10 h light (8am→6pm); 14 h dark (6pm→8am)
Spring/Autumn conditions: 22°C 12 h (8am→8pm); 10°C 12 h (8pm→8am) / 12 h light (8am→8pm); 12 h dark (8pm→8am)
Summer conditions: 30°C 14 h (6am→8pm); 15°C 10 h (8pm→6am) / 14 h light (6am→8pm); 10 h dark (8pm→6am)