Also known as
Prickly hakea, H. acicularis
Where is it originally from?
What does it look like?
Prickly, woody, spreading, evergreen shrub (<3m tall) with stiff, needle-like leaves (20-60 x 1 mm) with sharp pointed ends. Small sparse clusters of white flowers (winter- summer) develop into round, woody seed capsules (20-30 x 14-25 mm) with corrugated-surfaces, which contain winged black seeds (15-25 x 6- 12 mm).
Are there any similar species?
H. gibbosa leaves are always downy. H. propinqua.
Why is it weedy?
Tolerant of fire, damp to severe drought, moderate shade, poor soils, high to cool temperature. Long-lived seed, and moderately long-lived plants form dense stands, dominating other species in poor soils. Stock won?t graze it.
How does it spread?
Seed is spread by water and soil and livestock movement, and by dumped vegetation. Fire encourages seeds to germinate.
What damage does it do?
Dominates low shrubland and regenerating forest in very low fertility, poor soil habitats. Keeps sites dry, adds to fire risk, causes succession to pampas and grasses. Contributes to local extinction of rare native fern, orchid and shrub species. May decrease recreational use of an area because of spiny habit.
Which habitats is it likely to invade?
Gumlands, shrubland, short tussockland, bare land, fernland, especially burnt sites.
What can I do to get rid of it?
1. Leave for natural succession (8-20 years): can be accelerated by felling plants in sites of dense native vegetation, allowing native species to overtop Hakea. Best in winter to maximise regeneration and minimise fire risk.
2. Pull out small plants (all year round). Mulch.
3. Cut and fill (autumn): make 1 cut every 100mm around the trunk and fill each cut with 2g metsulfuron-methyl 600g/kg.
4. Cut trunk and paint stump (summer-autumn): cut trunk near to the ground, and swab freshly cut stump with metsulfuron-methyl 600g/kg (5g/L)
5. Overall spray (autumn): metsulfuron-methyl 600g/kg (5g/10L + penetrant). Best for small plants.
What can I do to stop it coming back?
Avoid fire at all times, implement fire protection strategy. Most sites can be left to regenerate to native species provided fire can be permanently avoided.