A Pair of Threatened Dandelions

New Zealand has three native members of the Sonchus genus, all of which are at-risk species. Two of the species, S. novae-zelandiae and the Chatham Island S. grandifolius are recent introductions into the genus after a move from Kirkianella and Embergia, respectively. Our native Sonchus are often overlooked as their appearance is often associated with the introduced pastural and suburban weeds. 

With no prior knowledge of Sonchus novae-zelandiae, I stumbled across it by accident and was instantly struck by the attractiveness of this small herb. The glaucous rosettes contrast nicely from its older yellowing leaves. Perched atop quartz rich Marlborough schist, its salty looking fine hairs and flower buds appear at home by the sea edge. Although, this herb makes its way up into subalpine areas as well. It has declined from much of its range, often surviving in refugia provided by cliffs and outcrops away from grazing animals and competition. It was a refugia like this where I found it at the end of a solid schist valley. The landowners refer to this as split rock, as tectonic movement has wrenched it apart. Down this valley now flows a stream of verdant green Selliera out to sea. 

At roughly the same latitude on the west coast, an uplifted knobbly reef foregrounds a sheer cliff of Nikau palm and coastal mosaic of plants. At the base of this, silvery calcareous mudstones host a cradle of Disphyma australe (Horokaka) and Sonchus kirkii. Such is a generally representative habitat for S. kirkii. This plant is thought to have grown in a range of habitats but now survives where faster growing exotic species cannot grow as easily. It can be distinguished from other species by the lack of spines on its large glaucous leaves. Sonchus kirkii can reach heights of a metre and can be treated as annual in the garden. Fresh seed will propagate readily and its role in coastal grassland-style gardens should be explored further.