Seeds of South Australia
Cressa australis (Convolvulaceae)
Rosinweed
List of species for Cressa
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Seed collecting:
January to December
Herbarium regions:
North Western, Lake Eyre, Gairdner-Torrens, Flinders Ranges, Eastern, Eyre Peninsula, Northern Lofty, Murray, Yorke Peninsula, Southern Lofty
NRM regions:
Adelaide and Mount Lofty Ranges, Alinytjara Wilurara, Eyre Peninsula, Northern and Yorke, South Australian Arid Lands, South Australian Murray-Darling Basin
IBRA regions
SUMMARY
Broughton (FLB02)Flinders Lofty Block
 Least Concern
Olary Spur (FLB03) 
 Least Concern
Central Flinders (FLB06) 
 Rare   (IUCN: RA d(ii))   [likes clay, low-lying areas]
St Vincent (EYB02)Eyre Yorke Block
 Least Concern   [Habitat specific, salt flats]
Murray Mallee (MDD02)Murray Darling Depression
 Near Threatened   (Probable Decline)   [restricted to river]
Murray Lakes and Coorong (MDD03) 
 Data Deficient   [acc. w/ river, 1 record]
Murray Scroll Belt (RIV06)Riverina
 Least Concern   [needs regular floods]
Myall Plains (GAW01)Gawler
 Rare   (IUCN: RA d(i,ii))   [in claypans & saltlakes]
Gawler Lakes (GAW03) 
 Rare   (IUCN: RA d(i,ii))   [in claypans & saltlakes]
Arcoona Plateau (GAW04) 
 Rare   (IUCN: RA d(i,ii))   [in claypans & saltlakes]
Dieri (SSD03)Simpson Strzelecki Dunefields
 Least Concern   [likes clay, low-lying areas]
Warriner (SSD04) 
 Least Concern   [likes clay, low-lying areas]
Strzelecki Desert (SSD05) 
 Least Concern   [likes clay, low-lying areas]
Oodnadatta (STP02)Stony Plains
 Least Concern   [likes clay, low-lying areas]
Murnpeowie (STP03) 
 Least Concern   [likes clay, low-lying areas]
Macumba (STP05) 
 Least Concern   [likes clay, low-lying areas]
Witjira (STP06) 
 Least Concern   [likes clay, low-lying areas]
Baltana (STP07) 
 Least Concern   [likes clay, low-lying areas]
Sturt Stony Desert (CHC02)Channel Country
 Least Concern   [likes clay, low-lying areas]
Diamantina-Eyre (CHC04) 
 Least Concern   [likes clay, low-lying areas]
Coongie (CHC06) 
 Least Concern   [likes clay, low-lying areas]
Everard Block (CER03)Central Ranges
 Rare   (IUCN: RA d(i,ii))   [edge of range; likes clay, low-lying areas]
IBRA regions
DISPLAY ALL
3 of 6 subregionsFlinders Lofty BlockLeast Concern
, Rare
St Vincent (EYB02)Eyre Yorke BlockLeast Concern
  [Habitat specific, salt flats]
2 of 6 subregionsMurray Darling DepressionNear Threatened
, Data Deficient
Murray Scroll Belt (RIV06)RiverinaLeast Concern
  [needs regular floods]
3 of 8 subregionsGawlerRare
3 of 4 subregionsSimpson Strzelecki DunefieldsLeast Concern
5 of 7 subregionsStony PlainsLeast Concern
3 of 4 subregionsChannel CountryLeast Concern
Everard Block (CER03)Central RangesRare
  (IUCN: RA d(i,ii))   [edge of range; likes clay, low-lying areas]
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 Cressa]
SA Flora:
Flora of South Australia Edition 5
Name derivation:
Cressa from the Latin 'cressa' meaning Cretan; referring to the first collection of the genus Cressa from the Island of Crete. Australis means of or from the south; referring to the distribution of the species in the southern hemisphere. 
Distribution:
Found in the eastern side of South Australia, growing  in mostly clay saline soils in swampy areas, around inland salt lakes and coastal flats. Also found in all mainland states.
Status:
Native. Common in South Australia. Common in the other states.
Plant description:
Grey and hairy subshrub, with erect rarely prostrate stems to 20 cm high. Leaves sessile to shortly petiolate, ovate-lanceolate, to 8 mm long and 5 mm wide, acute. Inflorescence terminal with solitary white to pink flowers in axils of leaves. Flowers throughout the year.
Fruit type:
Brown globular capsule to 5 mm long, with one seed.
Seed collecting:
Collect capsules that are maturing, turning brown and contain hard seeds inside. Collect more capsules as not all will contain viable seeds.
Seed cleaning:
Place the capsules in a tray and leave to dry for one to two weeks. Then rub the capsules gently by hand or with a rubber bung 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.