Impact of blackberry on an endangered species
J.D. Briggs, NSW National Parks and Wildlife Service, PO Box 2115, Queanbeyan, New South Wales 2620, Australia.
A few rare or threatened plant species, e.g. Grevillea iaspicula, G. wilkinsonii, Discaria nitida and Astelia australiana, are known to have at least some populations under threat through habitat invasion by blackberry. This contribution focused on the threats posed to the nationally endangered G. iaspicula by blackberry invasion of its habitat. G. iaspicula is a shrub confined to limestone outcrops in the Wee Jasper area of New South Wales, where it survives at seven sites and has a total population of less than 250 mature plants. Five populations are located on private land and two are on public land.
Browsing by domestic stock and land clearing have been the major past threats to survival of this species. The remnant populations are threatened currently by rampant invasion of habitat by blackberry and sweet briar (Rosa rubiginosa). Of the $18 000 spent on recovery actions for this species, it is estimated that more than $5000 has gone to the control of the woody weeds blackberry and sweet briar. The various problems encountered by the NSW National Parks and Wildlife Service and the Grevillea iaspicula Recovery Team in achieving satisfactory control of these woody weeds were discussed.
Plant Protection Quarterly (1998) 13 (4) 179.