TRIP REPORT : Wharekauhau Stream, Ocean Beach / Palliser Bay; Battery Stream, South Wairarapa

 1 – 2 February 2003 :   Wharekauhau Stream, Ocean Beach / Palliser Bay; Battery Stream, South Wairarapa

Botanising one of the windiest spots in Palliser Bay, in the face of a stiff nor’wester was a challenge accepted by ten intrepid BotSoccers on an otherwise warm and sunny day.

The first stage covered the lower third of Wharekauhau Stream.   The two sides differ dramatically owing to the different deposits exposed in the cliffs.   The true left bank / cliff consists mainly of brown marine sediments, and the true right of grey, terrestrial, lacustrine and stream sediments.

The cliffs of marine deposits are wet in most places with seepages resulting in surfaces covered with vegetation.   The run-off at the foot of the cliff is forming a wetland which hosts mainly weeds.   This may be temporary, phenomenon because the main stream has been diverted by a mound of collapsed cliff upstream.

Senecio lautus.   Photo: Barbara Mitcalfe

The cliffs on the true right are mainly dry with scattered clumps of vegetation and collapsed mounds at the base.   Among the angular gravel on the braided bed of the stream were Raoulia tenuicaulis, R. glabra and Senecio lautus.

We ate lunch sitting on boulders reputed to be from ice-age scree, where we went to see some mature Coprosma crassifolia.   Sadly, they were half dead though we could see how grand they had been.   Four members returned to their vehicle from there.

We then continued upstream to the unnamed Hoheria Stream, a tributary of Wharekauhau Stream.   Sheltered in a hidden gully were mature kanuka and several “Hoheria Tararua”, adults, saplings and seedlings.   A flowering specimen was taken for Te Papa’s herbarium.   Here the group decided to continue botanising up the gully instead of the upper reaches of the Wharekauhau Stream.

As we proceeded up the stream it narrowed and became impassable so we climbed the steep true right face through beech forest to a grove of kanuka on a terrace for a scroggin break.   We then sidled up the gully but this proved very difficult owing to the density of scrub.   However we saw many interesting plants including the divaricating Pittosporum divaricatum and Gahnia pauciflora which grew in abundance as did Spanish heath.

On the spur, east of spot height 264, the dense low vegetation and high winds which impelled us to go down through tall kanuka to a farm road.   We then descended through a series of high terraced paddocks to the beach.

On Sunday, the plan to botanise the coast around Mukamukaiti was abandoned because of the gale, in favour of Battery Stream.   Permission to cross private property was kindly given by one of the owners, Annette Shaw.   We drove through several large paddocks dotted with magnificent ti kouka and totara and surrounded by low bush at the base of rising slopes.   A walking track beyond the fenceline took us through a small plantation of young Pinus radiata juveniles with a variety of native species making a comeback in their shelter.   This merged into a section of mixed-age beech species.   We noted trackside, a Myosotis sp. and Schizeilema trifoliolatum.

Following a track through a mixture of native scrub and weed species, we came to the dry stream bed of Battery Stream.   Some 500 m upstream the water disappeared into the gravel.   Our biggest disappointment here was to see the stream lined on both sides with willows, said to continue almost to its headwaters.   From this point we returned to our cars and made a brew in a real ‘Thermette’.

Participants: Arnold, Gavin and Ruth Dench, Pat Enright, Barbara Mitcalfe, Olaf John, Sunita Singh, Kate Zwartz and Chris Horne.

Sunita Singh

Ed: we thank Sunita for the cosy accommodation in and around her bach near Corner Creek.