Searching for rare plants in Northland
At the end of November 2011, Philip Smith set off to isolated parts of Northland with Guy Bowden and Terry Hatch, to search for rare native plants in the wild. Experiencing plants in their natural habitats is important, for one learns lessons that may be applied in their cultivation (both practical and aesthetic). Trips like this also enable us to tell some of the stories of native plants (and show images) on the 'Plants' section of the website.
The main purpose of the trip was to visit the Waima Range, a chain of peaks and ridgelines that stands above the Hokianga, and includes the highest point of mainland Northland. In the last thirty years, three new species of tree or shrub have been discovered in the high points of Waima Range, all of them confined to the area. A new plant profile can be found on one of these species, Ackama nubicola, on the website, whilst a photo of another, Olearia crebra, is shown below (growing on a cliff at one of the highest points).
Other than those two endemic species, other interesting plants that occurred along the way were an unusual sub-shrub with electric blue flowers (Colensoa physaloides), fine specimens of a newly-described species of turutu (Dianella latissima), a beautiful, white-flowered, climbing rata of the north (Metrosideros albiflora), and an enigmatic shrub of moist habitats, Ascarina lucida (otherwise known as hutu).
The Hokianga district is also home to one of the last remaining natural populations of the popular, yet threatened, Hebe speciosa (titirangi). In addition to finding H. speciosa at South Head (on the Hokianga Harbour), this trip also afforded the opportunity to see this vibrant-flowered shrub in another one of the few sites that it still inhabits, Maunganui Bluff (pictured, below right).
Maunganui Bluff is a craggy, volcanic promontory that overlooks the coastline to the south of Waipoua Forest. It is well known for the interesting assemblage of native plants that grow there, including an unusual large-leaved form of waiuatua (Rhabdothamnus solandri) that was in flower in late November (this variant is similar to forms that grow on some offshore islands).
Also of special interest was the compact, mounding shrub, Coprosma aff. neglecta, whose near relatives grow on northern cliffs of New Zealand, and constitute excellent shrubs for establishing low-growing structure in the garden. We have utilised this plant a great deal in gardens; including the Maunganui Bluff form, which Oratia Native Plant Nursery has grown for a long time. For low shrub plantings, it has a natural charm that is lacking in so many of the sprawling Coprosma hybrids that are more frequently peddled in the trade.
Closer to home (especially for Guy, who is based out of Tutukaka) was a small remnant of swamp forest that represents one of the last vestiges of native vegetation from the once mighty Hikurangi Swamp. One the one hand, the treatment that this special patch of mostly divaricate trees and shrubs still receives is sad, considering its significance to the area (fencing is inadequate on certain margins, such that stock can regularly re-invade it). On the other hand, it is wonderful that the survivors that have endured are still present.
Foremost amongst these are a distinctive form of Hebe (that is potentially a new variety or species) and Pittosporum obcordatum, a nationally threatened small tree that we hold a special interest in (a juvenile plant is pictured below, with Terry and Guy for company). The latter forms shadowy columns that contribute a dynamic element to structural plantings, and bears copious amounts of tiny flowers that release an attractive scent in the evening. Despite having planted a huge quantity of P. obcordatum within gardens, this was the first time that Philip has viewed larger specimens of this plant in the wild.
