March in the hills with Chris Horne and Michele Dickson
Muehlenbeckia complexa agg, pōhuehue, pōhue, small-leaved pōhuehue, wire vine
Origin of the names
Muehlenbeckia is named after the Alsatian physician and botanist, Heinrich Gustav Muehlenbeck (1798-1845); complexa comes from the Latin word meaning ‘woven together, intertwined’; ‘agg.’ indicates that the form of the species is variable. Pōhuehoe, or pōhue, are Te Reo names for several species of climbing or trailing plants.
The February In the Hills included a description of Muehlenbeckia australis, which is also called pōhuehue. To avoid confusion, this month’s article uses the compound name: pōhuehue/wire vine.
Distribution and habitat
Pōhuehue/wire vine is native to New Zealand. It is not endemic, because it also occurs in Australia and South America. It grows on Te Ika a Māui/North Island, Te Waipounamu/South Island and Rakiura/Stewart Island. Look for the species in coastal, lowland and lower montane forests, especially on their edges, on open and rocky places, and on sandy areas near the coast.
Pōhuehue/wire vine is a much-branched liane/climber up to 6 m tall. It has many interlacing branches which may climb shrubs or small trees, or form tangled masses in the absence of support. The main stem is up to 5 cm diameter. The branchlets are very slender, circular in cross-section, hairy when young, and often finely ridged. They have dark to light reddish-brown bark.
The leaves are 5-20 mm long x 2-15 mm wide, dark green on top and paler, often whitish underneath. They vary in shape from egg-shaped, with the broad end attached to the flattened petioles/leaf stalks, to heart-shaped, with the notch at the base. The leaves range from leathery to thin. Several leaf forms occur on the same plant. The edges of the leaves are smooth, and usually not wavy. The petioles are up to 1 cm long. Plants may lose some or all leaves in winter.
Pōhuehue/wire vine is dioecious, meaning that female flowers and male flowers grow on separate plants. The wind and birds, geckos and skinks which feed on the nectar, move pollen from male flowers to female flowers to fertilise them. The clusters of white flowers are 1-2 cm long. The species flowers and fruits from November to February, and even as late as June. The seeds, about 2 mm x1.75 mm, are black, glossy, three-sided, and enclosed by persistent sepals which sometimes become white and fleshy. Birds spread the seeds.
In 1868, Colenso reported that the small, swollen, sweet, juicy, female flowers were a popular food with Māori children. Try eating the flowers in summer and early autumn to sample their sweetness! In 1896, F H Davey reported the species as “ … acclimatised in the Falmouth-Truro area of Cornwall” together with several other species of NZ plants.
Where to find pōhuehue/wire vine
The species is common in Wellington city’s coastal areas and rural hinterland, where it provides habitat for skinks, geckos, butterflies and moths. Look for it in the Tararua, Remutaka and Aorangi ranges, in many other ranges, and along our coasts, e.g. on sand dunes. As both a natural and restoration stabiliser of screes and older dunes, it forms compact springy clumps which can also suppress the spread of weeds.