Piripiri/Biddy-biddy Acaena novae-zelandiae
Native. Not threatened
This member of the rose family is common throughout the Ramsar dunes, in both wet and dry locations, it is also found in a few locations in the saltmarsh areas of the Estuary. Known around the rest of the world as the weed from New Zealand it has been classified as a noxious weed in many countries, being capable of growing in a wide variety of habitats ranging from coastal to alpine regions.
Their natural distribution, besides Aotearoa New Zealand is Australia and New Guinea. It has been introduced into the United Kingdom and is now classified as an invasive species there.
Anyone who has been tramping is familiar with the success of Biddy-biddy’s burrs in propagating the species. The inflorescence (group of flowers arranged on a stem) contains up to a hundred flowers, each with four hooked barbs. Apart from clothing, they are dispersed by, not only livestock, but any wind-blown vegetation that they can attach themselves too.