Botanical art
Prior names
Daviesia polyphylla, partly
Daviesia incrassata
Common names
Kangaroo Island Bitter-pea
Etymology
Daviesia named after the Rev. Hugh Davies (1739-1821), a Welsh botanist and an Anglican clergyman. Asperula from the Latin 'asper' meaning rough, referring to the slight roughness of the branchlets and phyllodes.
Distribution and status
Endemic to South Australia and found mainly on Kangaroo Island with outliers on southern Eyre Peninsula and a single record from the tip of Fleurieu Peninsula, growing on poor soils of sand or laterite in mallee or open-forest. Native. Uncommon in South Australia.
Herbarium regions: Eyre Peninsula, Kangaroo Island
AVH map: SA distribution map (external link)
Plant description
Compact or spreading shrub to 2 m tall, the branchlets greenish, with several longitudinal minutely scabrid ribs. Phyllodes subulate, compressed laterally or subterete, recurved only near the base; to 30 mm long and 1.5 mm wide, tapering from the base into the pungent point. Flower-spike a raceme with 2-3 orange or yellow with a deep-red-centred pea-flowers. This subspecies differ from Daviesia asperula ssp.obliqua which has a shorter and broader leaves. Flowering between September and October. Fruits are brown broad-triangular pod to 14 mm long and 10 mm wide, with one seed inside. Seeds are brown with black mottled globular reniform seed to 6 mm long and 4.5 mm wide, and a cream aril. Seed embryo type is bent.
Seed collection and propagation
Collect seeds between November and January. Collect maturing brown seed pods from the plant, using secateurs or by hand. Plant is prickly so it is advisable to wear gloves. Leave the pods in a paper bag to dry for at least a week. Rub the pods gently with a rubber bung to dislodge the seeds. Use a sieve to separate the seeds from unwanted material. Store the dried fruit heads with a desiccant such as dried silica beads or dry rice, in an air tight container in a cool and dry place. From one collection, the seed viability was high, at 90%. This species has physical dormancy that needs to be overcome for the seed to germinate (e.g. nicking or softening the seed coat).
Location | No. of seeds (weight grams) | Number of plants | Date collected | Collection number Collection location | Date stored | % Viability | Storage temperature |
---|---|---|---|---|---|---|---|
BGA | 1,426 (20.49 g) | 106 | 8-Jan-2004 | MKJ13 Kangaroo Island | 1-Sep-2004 | 95% | +5°C, -18°C |
BGA MSB | 900 (10 g) 1,000 (11 g) | 50+ | 15-Dec-2015 | TST1233 Kangaroo Island | 2-May-2017 | 90% | -18°C |