Silky hakea

Habitat

• Natively inhabits warm temperate coastal areas, heaths and the understory of dry sclerophyllous forests
• Inhabits disturbed areas such as roadsides, forest margins, coastal grasslands, pine forests, and arid areas prone to wildfires
• Found to occur on well-drained sandstone and quartzite soils, with low nutrient levels
• The presence of schist in the soil is a good predictor of distribution for the European invasions

Description

• A prickly, wooded shrub or tree growing up to 4.5m tall and living up to 30 years
• It has angular stems with thin brownish bark
• Young stems have fine silky hairs, but these quickly become dark-green needle-shaped leaves
• Groups of 4-5 cream-coloured flowers with white hairy stems form from the leaf axils
• Flowering in European invasions is from December to April
• Heat resistant woody fruits, containing 2 winged seeds, are formed in each leaf axil
• Fruits accumulate on the plant until it dies
• Fire is a key part of the lifecycle, killing the plant but stimulating the fruits to release seeds
• Seeds can disperse up to 7km and can reach densities of 7500 seeds/m²

Origin and Worldwide Distribution

• It is native to Queensland and New South Wales, Australia
• It has been introduced to South Africa, New Zealand, France, Spain and Portugal

Potential or Known Impacts

• Dense stands of H. sericea increase wildfire intensity, killing both native seeds in or on the soil and plant species which regenerate vegetatively
• It can reduce species richness, and alter the plant community structure
• Suppresses and excludes native vegetation and associated fauna
• Dense thickets are impenetrable and restrict human access
• Thought to reduce water runoff and restrict stream flow

Is it found in Northern Ireland?

• It is not currently present in Northern Ireland

How could it get here?

• The spread of H. sericea is a result of the plant trade, where plants historically used in landscaping, for hedges, or ornamental purposes have escaped the confines of the garden
• Illegal import, breeding, growth, release, selling and transport of the plant is the most likely reason for introduction today

Management/Methods for Prevention

• Prevention via enforcing the IAS (Enforcement and Permitting) Order (Northern Ireland) ensuring that H. sericea is not introduced to Northern Ireland
• Reporting any sightings so that Rapid Response can be instigated
• If Rapid Response is not successful, management can include physical, biological and chemical control

Current Legislative Position (Listed on 02 August 2022)

• This species must not intentionally be brought into the Union; kept; bred; transported to, from or within the United Kingdom, unless for the transportation to facilities in the context of eradication; placed on the market; used or exchanged; permitted to reproduce, grown or cultivated; or released into the environment.

Species Related Files:

RA_Hakea_sericea_Silky_hakea