Spring bush walks with Shirley Kerr
A walk along any of the local bush tracks in the spring will reveal many pleasant surprises if you keep your eyes open for 'the little things' of the bush. It is the time of the year to look for certain orchids. Many people are familiar with the large showy cymbidiums and these are what come to people’s minds when they think of orchids. However, our native orchids are generally quite tiny, and many stay unseen unless a special effort is made to locate them.

One that is more easily found, and which does look like a cymbidium, is Earina mucronata. It is epiphytic on trees but can be found growing quite low on tree trunks and also on rocks. Its thin stems and leaves droop downwards as do the clusters of creamy yellow flowers. On close examination, it is easy to see the similarities with the cymbidiums, except these flowers are only 7 -10 mm in diameter. The flowers are usually present from September to November, but can occasionally be found until late autumn. (There is another autumn-flowering Earina species - E autumnalis, which produces masses of tiny white flowers.)

A smaller epiphytic orchid, which can be difficult to spot is Drymoanthus adversus, although its foliage and roots do have an 'orchid look' to them. Flowering in late spring to early summer, its flowers are in small bunches hanging below, and often hidden by, the leaves. The flowers are only 3-4 mm in diameter, and appear to be a pale green, but are actually marked with little reddish dots.

Another epiphytic orchid which does not look anything like those above is Bulbophyllum pygmaeum. It consists of a tiny pseudobulb, about 3mm in diameter with a single green leaf about 2-3 mm across and 5-8 mm long. It can form mats on tree trunks and rocks, with the green wrinkled pseudobulbs linked by a stringy rhizome. The flower, which is only 1-2mm in diameter, appears on a short stalk from the base of the pseudobulb.

Ground dwelling orchids are not so easy to notice because they can blend in so well with their surroundings. One that is easier to recognize is the large green hooded orchid Pterostylis banksii. It can vary in size, from 10-20cm, with light green strap-like leaves. Each plant generally produces only one pale green flower, 3-4cm high, with long ‘tails’ on the lateral sepals. Another species of green hooded orchid is Pterostylis trullifolia. Its flower is smaller than P. banksii, and its foliage consists of small heart-shaped leaves in a rosette, with smaller strap-like leaves growing up the stem.

The Corybas or spider orchids can be found flowering in spring. I have found four species so far in this area. Each produces a single leaf and a single pale green and purple flower. The flowers have four long filaments extending from the petals and sepals and it is easy to see why they were given the name 'spider orchid'. The most common is C. trilobus, but would be easy to miss unless the foliage is first noticed. Leaf shape within this species can vary and most of the plants I have found have leaves I would describe as butterfly shaped, 2-3 cm wide. It flowers from August to early September. Flowering a little later is C. acuminatus and its leaf, 3-4 cm long, is easy to recognise as being heart shaped. Another spider orchid, C. oblongus flowers in October, followed by C. ‘kaimai’ which flowers in November.

Appearing in late spring as two oval leaves hugging the ground is Chiloglottis cornuta . It flowers from November through the summer, and often found alongside the track. It has a single pale green flower, and on close examination, dark red calli can be seen inside on the labellum.

Another ground-dwelling orchid with a single heart-shaped leaf, but belonging to a different genus, is Acianthus sinclarii. The leaf is raised off the ground, about one-third of the way up the stem which can produce 2-6 green flowers each about 5mm long. This species flowers in the late winter-early spring. Plants can vary between 5-10 cm in height.

Other interesting plants to observe are the flowering trees and shrubs at this time of the year, some of which you can detect with your nose before you see them. One such plant is Geniostoma ligustrifolium, known as hangehange. Its flowers are very small, and being greenish white, are difficult to see on the plant, but can found lying on the ground when they fall. Another strongly perfumed shrub is Alseuosmia macrophylla. Its flowers are 3-4 cm long, tubular and a bright crimson colour with frills on the lower edges of the petals.

A small spreading herb, Pratia angulata, can be found closely hugging the ground. Without its white flowers or purplish red berries, it could easily go unnoticed. It belongs to the lobelia family, and if you are familiar with flowering lobelias in a garden, you will recognize the similarity in the flowers.

These plants can all be found alongside any of the local bush tracks without having to venture from the track at all. It is a matter of timing and taking time to stop and observe the ground at your feet, and the trees beside and above your head.

A useful book to cart with you on your bushwalk is The Nature Guide to New Zealand Native Orchids by Ian St George, published by Godwit, 1999.

Visit Shirley's excellent website: www.kaimaibush.co.nz

Pterostylis banksii
Corybas acuminatus
Corybas oblongus