Regenerating Kauri stumps and other Trees

Kauri stumps and head were left behind from the logging industry

The forest was cut over for Kauri in the 1920s so it has been 100 years since these trees were killed and the stumps left.

Fire and grazing by goats, possums and others have impacted on the plants colonizing these stumps.

Regenerating Kauri heads are

The Kauri head is where the tree branched out. The millers only wanted knot ( where the branch comes into the trunk) free timber so once the tree was felled the heads or tops were cut off and the rest of the tree was taken away. An indication of the height of the tree can be guessed at by the distance the head is from the stump.

Plants colonising fallen trees is a natural process

All trees at some stage fall and so regeneration is a standard process. The timber breaks down forming humous and a variety of plants establish themselves.

In a number of cases for example epyphites establish tmemsilves before the tree falls sucj as northern rata.

There are 100s of stumps and heads through out the forest

Cordyline Banksii Found on open steep face

There are at least five species on this stump

• Mingingi
• Astella
• Tanekaha
• Scarlet rata
• Rewarea

The Tangihua Forest surrounding the lodge was heavily logged in the early 1900s. The easier country was then burnt and developed for farming. The steeper country remained in its original state.
The land surrounding the lodge was eventually sold to the government by the then owners (Smiths) who moved down stream to better country.
This land was then leased for grazing until 1970. It was not heavily stocked but fires, cattle, pigs and goats kept the clearings open. A heavy infestation of goats also prevented the under canopy of the standing forest from regenerating. Many of the goats were removed in the 1980s goat boom or hunted out, but some remain.

At this stage the forest is regenerating but animals such as pigs goats possums, rats, mice and wasps still have a significant impact.

Examples of Native forest regeneration Stages

The first plants in a cleared area are called pioneer plants. They arrive either by wind, birds or are residual seeds which can survive fire or remain under ground for long periods with out germinating. These plants can germinate in the open and grow quickly. This is usually grass and weeds such as thistles and other introduced species. A native pioneer species is Bracken fern which will establish with or just after the grass.

They are often followed by Manuka. Manuka seedlings germinate prolifically, thousands to a square metre. These compete intensely for nutrients, water and light.

Over time most mānuka seedlings and saplings will die, until just one tree dominates every few square metres. The manuka will grow to 5 or 6m and provides a thick shady cover. Underneath this other native plants get started.

Manuka will die off after about 30 years. Often Kanuka will establish with the Manuka and will grow taller and survive upto 150 years. Kanuka will be part of stage two and three becoming the dominate species until replaced by confers and broad leaved trees.

Trees which establish earlyunder kanuka are Rewarewa, Nikau, Kowhai, Lancewood, Cabbage trees.

Later to establish are the taller emergent species like Rewarewa, Rimu, Totara, Matai and Kahikatea. Under these trees only the more shade tolerant canopy species such as Kauri, Tawa, Kohekohe, Hinau and Kamahi can survive. Eventually, the colonising species are replaced by tree ferns, climbing and perching plants and a climax forest is reached. The cycle continues as trees fall through decay or wind, flood or fire.

Other Regeneration examples which can be observed

The road to the lodge

Lodge road

All along the lodge road you will see examples of regeneration. From the gate to the bush edge you have grasses and plants such as manuka, Gorse, and blackberry. On the bush edge there are other trees such as Lancewood, cabbage trees, and Totara. All these trees are unpalatable to stock and so can withstand grazing pressure.

Inside the forest where grazing is not an issue but lack of light is we have different species. Beside the road is grass and weeds which regenerate after regular spraying. Further in are ferns, punga, pitosporums, manuka. On banks with limited top soil are plants which fix nitrogen such as Tutu.

Around the lodge are Manuka, Rewarewa, Kowhai.

Nature trail

This is an area where we have identified a wide range of plants and are developing teaching resources for teachers. See Nature trail identifying Northlands native plants

This area was logged and then cleared for grazing. It has become established longer but been effected by grazing from goats pigs possums and cattle.

Regenerating on logs and stumps

When the kauri trees were cut down only the good timber was taken out with the stumps and the heads (where on mature trees the straight trunk ends and the branches occur) left.

These have become habitats for a wide range of plant and animal species.

There are many examples of this on the Nature trail. These trees were cut about a century ago in the 1920s

References

it is very apparent that specific information has been shared online between many organisations. Attributing to the initial source is impossible. As much as possible we use our own photos but this will take time and for extinct birds that is not possible. We have used the following websites as sources for our information

• Te Ara The Encyclopaedia of New Zealand
• Wikipedia
• DOC website.
• T.E.R:R.A.I.N Taranaki Educational Resource: Research Analysis and Information Network