A preliminary assessment of the establishment and persistence of Berberis darwinii Hook., a naturalised shrub in secondary vegetation near Dunedin, New Zealand

Abstract

A preliminary assessment was made of the establishment and persistence of Berberis darwinii in secondary vegetation dominated by native trees. B. darwinii seedling establishment on cleared ground and in forest considerably exceeded that of native shrub and tree species. B. darwinii showed continuous recruitment in stands surrounded by rough pasture, in low forest established since 1974 and 1942, and in secondary forest mature in 1942. It persisted in secondary forest for at least 40 years, but diameter growth rate and height relative to the canopy were lower with increasing vegetation age, so B. darwinii plants became increasingly confined to the understorey. Native species diversity was little reduced by B. darwinii in the vegetation age range of the study. Comments are made on the conservation implications of B. darwinii population dynamics, with suggestions for further research.

Keywords:

• Berheris darwinii
• secondary vegetation
• naturalised woody weed
• Dunedin Ecological District