Trip Report – 2.2.2013:   Wainuiomata River – west branch

Urtica incisa.   Photo:   Jeremy Rolfe.

The valley of the west branch is at the heart of this pre-European climax forest.   Here emergent podocarps, rimu, kahikatea, miro and matai, and northern rata, heavily laden with epiphytes, form a distinct upper tier.   Canopy species include tawa, hinau, rewarewa, pukatea, black and white maire and kamahi.   Plants of the sub-canopy include putaputaweta, kanono, a shade form of Coprosma rubra, broadleaf, mahoe, wheki-ponga and soft tree fern, on whose trunks we found several raukawa (Raukaua edgerleyi), and the strap fern Notogrammitis pseudociliata.   We saw numerous examples of ground-cover species including Australina pusilla, pennywort (Hydrocotyle elongata), scrub nettle (Urtica incisa), and Uncinia distans.   A patch of waoriki (Ranunculus amphitrichus) on the track appeared to have come from a small wetland to the east, which contained duck weed Lemna minor, kanuka, rohutu and swamp maire.   On an undercut, shady, river bank, we found the bristle fern Abrodictyum elongatum.   The dense canopy confined weeds to light-wells caused by windfalls and canopy gaps along the river.

We thank Greater Wellington Regional Council ranger, Grant Timlin, for permission to visit this special place, and wish the council well with the ‘mainland island’ restoration project.   Sixty N.I. robin from Kapiti Island were released in the area on 15/8/12, joining fourteen N.I. brown kiwi now resident after releases, a few years ago, in the valley of Turere Stream, a tributary of the Orongorongo River.

Participants :     Peter Beveridge, Jill and Ian Goodwin, Bryan Halliday, Anthony Hill, Chris Hopkins (leader/scribe), Chris Horne, Sheena Hudson, Rodney Lewington, Barbara Mitcalfe, Leon Perrie, Grant Roberts, Nick Saville, Lara Shepherd, Darea Sherratt, Nina Zimowit.