Plants of
South Australia
Pultenaea trifida
Leguminosae
Kangaroo Island Bush-pea
Display all 13 images
Regional Species Conservation Assessments per IBRA subregion.
Least concern
Near threatened
Rare
Vulnerable
Endangered
Critically endangered
Extinct
Data deficient
Adelaide
Arkaroola
Ceduna
Coober Pedy
Hawker
Innamincka
Marla
Marree
Mount Gambier
Oodnadatta
Renmark
Wudinna
Keith
Yunta
Enlarge Map
Copy Map
Copy Map
Display IBRA region text

Botanical art

Kath Alcock painting: 1.

Etymology

Pultenaea named after Richard Pulteney (1730-1801), an English physician, botanist and biographer of Carl Linnaeus. Trifida from the Latin 'trifidus' meaning split into three; referring to the tri-dentate bracteoles just below the calyx tube.

Distribution and status

Endemic to South Australia and found only on the western end of Kangaroo Island, growing in heath or mallee (Eucalyptus remota) on sands or yellow-brown sandy loams over laterite or ironstone. Native. Rare in South Australia.
Herbarium region: Kangaroo Island
NRM region: Kangaroo Island
AVH map: SA distribution map (external link)

Plant description

Erect to prostrate shrub to 1.5 m high, branches with white and rusty hairs. Leaves alternate, to 8.2 mm long and 3 mm wide, ovate-elliptic to orbicular, flat to broadly u-shaped, straight to recurved, sparsely hairy above and densely hairy below. Inflorescences 1 or 2 or a few, crowded terminally on short branches, or axillary with yellow to orange with red striation at front and back pea-flowers, with several bracts and trifid bracteoles inserted just below the calyx tube. Flowering between September and November. Fruits are hairy brown ovoid pod to 4.5 mm long. Seeds are dark brown with black mottled reniform seed to 2.2 mm long and 1.5 mm wide, with a cream aril. Seed embryo type is bent.

Seed collection and propagation

Collect seeds between December and January. Collect maturing pods, those that are brown or turning brown and contain dark hard seeds inside. Place the pods in a paper bag and leave to dry for one to two weeks. Then rub the pods 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. Seed viability is usually high. This species has physical dormancy that needs to be overcome for the seed to germinate. The seed coat needs to be ruptured so that water can enter the seed before germination can occur. Methods to rupture the seed coat include scarification with sand paper or nicking the seed coat with a sharp blade or hot water treatment by immersion in boiling water.

Fire Response

Obligate re-seeder, only tiny seedlings noted emerging in fire scars and no re-sprouting observed.

Longevity: >20 years

Time to flowering: 4 to 5 years

Recovery Work

In 2020-2021 this species was assessed post-fire in 1 year and 2 year old fire scars. A total of 100 seeds have been collected & banked for a population outside the 2020 fire scar. Further populations will be assessed and seeds collected on Kangaroo Island in 2021–2022. Germination screening testing the response to fire cues will be undertaken in 2021.This project was supported by the Project Phoenix program.

Seeds stored:
  Hide
LocationNo. of seeds
(weight grams)
Number
of plants
Date
collected
Collection number
Collection location
Date
stored
% ViabilityStorage
temperature
BGA 
MSB
1,450 (3.3 g)
1,450 (3.3 g)
40+17-Dec-2015TST1259
Kangaroo Island
2-May-201795%-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:
  Display