New Zealand planted pine in response to Cyclone Bola – with dire consequences

During Cyclones Hale and Gabrielle there was again extensive damage in Tairāwhiti due to poor management of exotic plantations – mainly pine. Critical public infrastructure destroyed; highly productive agricultural and horticultural land cleared or planted; removed houses, fences and sheds; the lives and dreams of people gone; dead people.

The impacts on natural ecosystems are not yet known, but there will be significant damage to terrestrial, freshwater and marine environments. Similar damage occurred during storms in June 2018 and July 2020.

Although heavy rain and flooded rivers are a major factor, most of the damage is caused by sediment and slash from plantation removal.

Slash is the woody material (including large logs) left after harvesting in commercial forests.

Landslides in harvested sites pick up the material and carry it downstream, causing significant damage. All the evidence from Cyclone Gabrielle shows that much of the damage was caused by radiata pine slash.

A legacy of poor land management

Sediment and cuttings from exotic tree cultivation sites were established as major factors in the damage caused during the June 2018 Tolaga Bay storm in recent court cases taken by Gisborne District Council.

Five plantation companies were found guilty and fined for breaching resource consent conditions in relation to their management practices.

Multiple groups have called for an inquiry into the way plantation harvest sites are being managed in Tairāwhiti and elsewhere.

But given the severity and ongoing nature of these impacts, isn’t it time we move beyond focusing on management practices and address the broader underlying issues that have fueled this situation?

These latter causes are complex but primarily related to poor historical land management decision-making and human-caused climate change.

Among the main drivers of the current problems in Tairāwhiti are the large areas of exotic tree plantations established with government support after the devastation of Cyclone Bola.

But this devastation also reflects earlier poor land management decisions to clear the native forest of steep, inodible hillside land in the late 19th and early 20th centuries, which also encouraged the government of the day.

Climate change on the horizon

Man-made climate change is the cause of the other disaster. atmospheric CO₂ levels are now 150% above pre-industrial levels and climates are rapidly changing and unprecedented new events are emerging.

Although rising global temperatures are the most obvious aspect of human-induced climate change, the increasing frequency and intensity of extreme weather events has the greatest impact on people and the environment.

Accountability of the forestry sector in Tairāwhiti and elsewhere is vital. But we also urgently need to address the root causes because no matter how strict the rules are about harvesting, storm events will become more frequent and more severe.

Time for urgent action

With over 40 years of experience researching forest ecology and sustainable land management in Aotearoa, I believe there are four key areas where we need to act urgently to address these issues.

1. As a country we must rapidly reduce greenhouse gas emissions and rapidly increase CO2 uptake₂ out of the atmosphere. These are national issues and not limited to Tairāwhiti but as a nation we seem to be sleeping in our response to the climate emergency.

2. A comprehensive catchment assessment is needed across all of Tairāwhiti (and likely other areas in Aotearoa) to identify those plantations that are located in the wrong place in terms of potential harvesting impacts. No further harvesting should take place in the Tairāwhiti plantations until this exercise has been completed. We also need to identify those areas that currently lack plantings but should never be planted with exotic tree crops (for any purpose).

3. The government must then buy out the current owners of these plantations and undertake a program of careful restoration to native forest. This will come at a cost, but it must be done. We already have models for this in Tairāwhiti where Gisborne District Council has started converting pine forests in their water supply catchment to native forests.

4. Finally, we need to establish many more native forests across all of Tairāwhiti, and in Aotearoa in general, to help build resilience in our landscapes.

The consequences of short-term thinking

For too long we in Aotearoa have been fixated on maximizing short-term returns from exotic tree crops without thinking about long-term consequences. The legacy of this arrangement is now bearing heavily on us as the climate emergency exposes the risks of poorly located and poorly managed exotic tree crops.

And we are now making the same mistakes with exotic carbon tree crops, once again leaving an unacceptable legacy for future generations to deal with because of a focus on short-term financial gains.

Forest policy in Aotearoa is dominated by exotic tree plantations and we urgently need to shift this to a focus on diverse native forests.

Our native rainforests provide so many benefits that exotic tree crops can never provide. They are vital to the conservation of our native biodiversity, providing habitat for many species of plants, animals, fungi and microbes. They also regulate local climates, improve water quality and reduce erosion. This helps to maintain a healthy freshwater and marine environment.

Indigenous replanting initiatives promoted by charities such as Pure Advantage must be a key focus of forest policy in Aotearoa now and into the future.

This article from The Conversation is republished under a Creative Commons license. Read the original article.