July 3, 2013

Mistletoes are intriguing plants – due in large part to their parasitic nature, as well as the unusual sight that evergreen clumps of mistletoe form upon the bare branches of deciduous trees in winter. Within New Zealand, we have 9 native species of mistletoe (one of which is now sadly extinct). Two of these, from the endemic genus Peraxilla, produce beautiful red flowers en masse in early summer.

The flowers that are pictured herein are from the species Peraxilla tetrapetala in full bloom at Lake Ohau during last November. At the same time, the beautiful yellow flowerheads of Bulbinella angustifolia (below, right) emerged from grassland on the roadside.

The photograph on the left, below, shows the flowerbuds in their unopened state. Some of our native mistletoes have a remarkable relationship with native birds (and even some of our tiny native bees), wherein the pollen-laden flowers open explosively when certain birds (notably tui and bellbirds) tap the ends of the buds.

This provides an effective form of pollination, on the assumption that a sufficient number of birds remain within these ecologies to play their role. Accordingly, the decline of many of our native birds is one factor in the increasing rarity of our two species of Peraxilla.

The image below shows the specialised roots of the mistletoe, some of which (called haustoria) bore into the host plant (in this case, one of our small-leaved Coprosma species).