Rooted to the spot: why we need to introduce more plants

Jim Douglas is a scientist at Crop & Food Research Mana Kai Rangahau, in Hamilton

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The free flow of plant species around the world has been a key factor in the economic and cultural development of most nations. New Zealand is no exception: our country would be a poor and hungry place without exotic species, because it has no significant economic crops, food plants, pasture grasses or legumes of its own.

The inflow of exotic species has made New Zealand a productive and wealthy nation. The process began with Polynesian migrants bringing in kumara and taro (origi­nally from South America and Asia, respectively). Today our land-based export products from agriculture, forestry and horticulture are derived almost exclusively from exotic spe­cies. In 2003-04, $18.5 billion, or 64 per cent of New Zealand’s export earnings, came from these industries, profiting from plant species originally sourced from all over the world.

Flax is the only native New Zea­land species to have been cultivated and exported to significant economic advantage, but the flax industry died with the advent of synthetic fibres. Global change and new discoveries that create and destroy markets are inevitable, and we need to be flex­ible and innovative if we are to make the most of such change and new opportunities.

In addition to their importance to our export economy, locally grown exotic plants provide much of our food and drink and dominate large parts of the rural landscape, as well as the parks, playing fields and gardens in our towns and cities. We take our surroundings and what we eat and drink for granted, but the exotic species we use were all—at one time—introduced.

New Zealand’s generally benign environment allows us to grow a huge range of plant species. This capability has elevated gardening to a national passion, second only to walking as a popular pastime. New Zealand’s 1.6 million garden­ers thrive on finding something new to grow. Today it is estimated that there are around 40,000 exotic plant species in New Zealand compared with 2450 native species, a ratio of 16:1. Forty thousand may seem a lot of exotics, but it represents less than 10 per cent of the world’s esti­mated flowering plant flora of some 422,000 species. The New Zealand flora, outside our national parks, crown lands and scenic reserves, is now dominated by exotic species. This is our plant-based economy at work; not only do exotic plants sup­ply our exports and our sustenance, but they provide the diversity, flow­ers and autumn colours that tourists admire.

I have spent 40 years working as a plant scientist in grassland, arable crops and horticultural development, the past 20 on plant introduction and new-crop development. For me this has highlighted the large number of plant products that exist in the world’s markets and the op­portunity they give us to diversify our economy and enhance our lives. As a trading nation, we need to be at the forefront of international market developments. We can only remain there through innovation and the development of new products. Government recognises this and has extolled the need to develop an in­novative society to lift New Zealand up the OECD rankings.

However, we also need policies that actively assist such develop­ment. Our wealth creation in the past has been built on introduced plants, so imagine if the free flow of plants into New Zealand was stopped. This may sound unthinka­ble for a country that depends on ex­otic species, but this in effect is what happened when the Hazardous Sub­stances and New Organisms (HSNO) Act became law in 1998. Over the seven years since then, only two new plant species have been brought into New Zealand (Australian grass trees), whereas prior to the Act an estimated 500-600 new species were introduced annually. Access to the world’s plant resources and the potential they hold for our future economic benefit (and gardening enjoyment) has been blocked by government legislation.

Today, a plant species can be imported only if it is on the Ministry of Agriculture and Forestry (MAF) biosecurity list of acceptable species, which is based on species already known to be growing here. The MAF list comprises approximately 27,000 species, but unfortunately this is only around 67 per cent of the estimated number of species in the country. Nevertheless, MAF uses this incom­plete list at the border to prevent entry into the country of species not on it. Understandably, people bringing in precious seed become highly irritated when it is confiscated at the border yet they know the spe­cies concerned is already present in New Zealand and that MAF simply doesn’t have it on its list.

Considering the enormous task of listing all exotic plant species in New Zealand and keeping up to date with nomenclatural changes, it has to be questioned whether the current regulations are necessary or just bureaucracy gone mad. What is their purpose? If it is to deny entry of unwanted species, as seems to be the case, the focus of the list should be unacceptable species, not accept­able ones.

If a plant species is not on the MAF list, it comes under the juris­diction of the HSNO Act and must satisfy an environmental-risk assess­ment before it can be placed on the list. This work is undertaken by the Environmental Risk Management Au­thority (ERMA). The current fee for a full environmental-risk assessment for release of a new plant species (a “new organism” under the Act) is $33,750. For new plants not con­sidered likely to form self-sustaining populations there is a rapid-assess­ment process costing $562. These costs are borne by the applicant, but once approved for importation a species goes onto the MAF biosecu­rity list and subsequent importations are free. The lack of plant introduc­tions since the HSNO Act became law indicates that the regulations and their costs are a major barrier to the introduction of new species.

Under today’s regulations it is doubtful whether the world-ranked plant collections at Pukeiti (in Taranaki) and Eastwood Hills (near Gisborne), or in any of our botanical gardens, could have been estab­lished. Plant collecting is itself the first step in developing new plants for commerce. Establishing a new fruit or crop here could entail col­lecting dozens of species of interest from around the world, establishing hybrids and evaluating them, as has been done (and is still continuing) with kiwifruit varieties. Modifica­tion of the HSNO Act in 2003 to allow risk assessment of new plants by genera or family was intended to simplify new species importations but didn’t overcome the cost factor. Low-cost breeding began our calla lily and Sandersonia flower indus­tries, and it is important that regula­tion and cost do not stifle this type of innovation.

Of course, the purpose of the HSNO Act (in the context of plants) is to protect the environment, and ourselves, from the any adverse ef­fects new species might have. Exotic plants are, however, so fundamental to our economy and way of life, and so predominantly beneficial to the environment, that it is difficult to comprehend what the legislation is actually protecting and why plants are included under the HSNO Act at all. Of the estimated 40,000 exotic plant species in New Zealand, only 162 (or 0.5 per cent) are listed as pest species. That is a pretty good record after 170 years of plant im­portation, during which many weeds were unintentionally introduced in pasture-seed mixtures before today’s quarantine requirements regarding purity and cleanliness of seed and packaging were established.

The Biosecurity Act is the ap­propriate legislation for dealing with pest species, but it is repressively bureaucratic to evaluate all new species coming into New Zealand for environmental risk when history indicates that the vast majority pose none. Furthermore, assessment of environmental risk is an inexact sci­ence, as it is generally uncertain how well a plant will grow here, what risks it presents or what economic potential it may have. A modern-day environmental-risk assessment of the Chinese gooseberry would probably not have allowed it into New Zea­land because it is a rampant vine, and yet from it has come today’s $2 billion kiwifruit industry.

Arguably, the HSNO Act is being used as a barrier to slow down the importation of exotic species so as to maintain the sanctity of our native flora. But today the flora of devel­oped New Zealand is a cosmopoli­tan mixture of exotics and natives, and we need to recognise that fact in our laws and regulations. On the one hand we need to protect native flora in national parks and reserves as our heritage, but on the other hand we need to have easy access to the global flora because this is our livelihood and our future. In my view, there are good arguments to remove plants from the HSNO Act and allow the free entry of all plants into New Zealand other than listed banned species. This system worked effectively in the past and allowed innovation and plant development to flourish.

Free access to the world’s flora is critical for the future development of New Zealand, because the use of plants in the modern world has expanded dramatically, far beyond considerations of mere beauty or simple utility. Global plant biodiver­sity is a key resource for devising solutions to the effects of climate change and the need for renewable energy. Plants are now also sought after for what they contain. They are the source of compounds for use in foods, cosmetics and medicines and are the building blocks for industrial products. Their beneficial charac­teristics are being identified at the molecular level and then used to improve other economically impor­tant plants. Our native flora makes up only 0.4 per cent of the world flora of seed-bearing species; conse­quently, the global resource is where our future lies.

We also need to take an ac­tive role in conserving valuable, unique, rare and endangered germ plasm from around the world. New Zealand could easily provide a safe haven for such material as a resource for the future, but the regulations don’t allow its free entry into the country.

If we are to grow an innovative society, it is vital we have free and open access to the world’s flora. Our futures depend on it. Government must take a leading role in providing a regulatory framework that assists in this regard rather than one that entails shooting ourselves in the foot with buckshot bureaucracy.

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