about New Zealand : Flora


An Ancient Forest

Isolation from other land masses has enabled New Zealand's flora to evolve along its own unique lines. Over 80 percent of its plants are endemic (only found in New Zealand).

Podocarps are more predominant in New Zealand than anywhere else. They are a type of conifer that are a seed producing plant, or gymnosperms. A Mesozoic era plant, Podocarps stretch back almost 200 million years. Members of this family include rimu, totara, miro, kahikatea, and matai.

Kauri trees are amongst some of the biggest trees in the world. They can grow up to 50 meters tall, with trunk girths of up to 16 meters. They were once common in the upper North Island but were extensively logged by European settlers who used the trunks of young kauri for ship masts and the mature trees for building. The gum was also used in the production of varnish.

Northern and southern rata are the best known of the rata species in New Zealand. They stand out in summer with their striking red/crimson flowers. These trees are an important source of nectar for native birds.

As well as supplying native birds with nectar the leaves are also eaten by introduced possums who have a preference for rata leaves. Possums can kill a mature tree in three years!

Even though New Zealand is a temperate country it has a large diversity of ferns. There are about 200 species ranging from the tiny filmy ferns that are about 20mm across to the tree ferns that can grow as large as 20 metres high. The silver fern is perhaps the most famous of all New Zealand ferns as it is proudly embroidered on the chests of our sports teams.

Harakeke - Flax
This plant was perhaps the most important plant to Maori. The fibre was used to make clothing, mats, baskets, ropes, fishing lines and nets. The stalks of the flowers were used to make rafts and floats.

Ecologically flax is just as important, it supports a large number of animals by providing both shelter and food (nectar). Although harakeke is often called flax, it's actually a lily.

Coprosmas There are more than 50 species of these small leaved, twiggy shrubs. It is very hard to identify the many different species and there are some that have yet to be named.

The uniqueness of the coprosmas is the divaricating varieties, there are 30 of these. They branch at wide angles and are interlaced to give the plant a tangled mess appearance.

Divaricating plants only occur in New Zealand and there are two theories as to why. The first is that they evolved that way to combat the harsh weather conditions by protecting the growing points from drought and frost, the counter argument to this is why didn't they evolve this way else-where in the world? The second theory and the one I like to believe is they evolved this way to protect the leaves from moa browsing, a moa was one of the largest birds in the world, ostrich like (extinct).

Different Adult and Juvenile Forms
Many New Zealand plants have different adult and juvenile forms. Like the coprosmas, many scientists believe this is a defense against moa browsing.

The most striking occurrence of this is lancewood, in fact early botanists thought that they were two completely different species. The adult has much smaller and rounder leaves and they are pointing up. The juvenile has very long narrow leaves that point almost straight down. The photo below doesn't show the true picture as there isn't a mature adult in it, although the one on the right is getting there.