Wilding conifers threaten landscape values, biodiversity and land-use options in the high country. In June 2012, the Minister for Primary Industries approved the development of a non-statutory strategy for wilding conifer management. The submitting Wilding Conifer Management Group (the strategy stakeholder group) identified priority needs for improving wilding conifer management. This project aims to meet these identified needs and inform the developing national strategy. The work will provide land managers and regulators with:
(i) A national monitoring and reporting framework for wilding conifers;
(ii) Cost analyses for specific wilding conifer control and management regimes based on actual costs incurred in different regions
(iii) A decision support system to understand wilding Douglas-fir spread better across the wide range of environments and site conditions
The project will enable stakeholders to report on long-term success, identify reasons for success and will contribute to the national strategy to manage wilding conifers in New Zealand.
Wilding conifers are exotic conifers that have regenerated naturally from seed outside planted forest estate. Species that are prone to create wildings are those that have a light wind dispersed seed. Key examples of spread prone species that produce wilding offspring are Lodgepole pine, Douglas-fir, Corsican pine and Scots pine. Within New Zealand, wildings are estimated to be dispersed within 805,000 ha in the South Island (2007 data) and within 300,000 ha in the North Island.
Considerable resources, time and money are spent annually on the control and management of wilding conifers in New Zealand. Wilding conifer spread concerns a wide range of organisations and parties, from Government departments and agencies (such as MPI, DOC, MfE and LINZ), territorial authorities (Regional and District councils), companies (such as Landcorp Farming and corporate plantation growers), to many private land owners/managers, particularly farmers. The expense that these stakeholders face to control, contain and manage wildings is often a significant part of their total land management budget. For example DoC is currently spending $6M on wilding control and the Mid Dome Trust has spent over $3M since 2007.
Based on previous work by researchers and the NZ Wilding Conifer Management Group (NZ WCMG) there is a general awareness and understanding by various organisations and groups of wilding conifer spread ecology and basic control strategies. However, this knowledge is not widely understood by all land managers and farmers, and there are still important knowledge gaps to be filled.
Previous effort has focused on determining potential control and management options for wilding conifers, and applying these methods across a variety of landscapes, and across a variety of species. Little work, however, has gone into providing clear methods for assessing the effectiveness of the control and management methods for wildings (e.g. re-occurrence of wildings) or into developing a standard reporting framework that allows clear and consistent reporting of outcomes, regardless of species or location. Work is also needed to provide an assessment basis that enables land managers to determine whether they are achieving their goals with respect to wilding control and management cost effectively. In order to accurately assess progress to date and to provide a clear platform for further work in the control of wilding conifers, the work identified above needs to be conducted now.
New risks are also emerging. Douglas-fir wildings - a result of seed rain from established planted forests - are becoming an increased threat risk. Due to the better structural wood and good growth rates that Douglas-fir trees offers over radiata pine trees grown in the high country of the North and South Island, Douglas-fir is the preferred choice for these forest growers. As many stands from the > 100,000ha Douglas-fir planted forest estate are now reaching coning age, the amount of seed from these planted forests will increase. This means that the risk associated with Douglas-fir wildings will only increase in the future, unless something is done now to mitigate against this risk. From the perspective of the forest owners, they are facing limitations as to where they can establish new Douglas-fir forests along with potential containment and spread management costs from existing planted forests. While Douglas-fir represents New Zealand’s second most planted exotic forest species (currently contributing approx. $200M to the economy), these factors in the future have the potential to negatively affect both forest growers freedom to operate, and neighbouring farms and other land.
The project will provide evidence and information to farmers, stakeholders, land managers and decision makers that will enable them to better manage and control wilding conifers efficiently and successfully, thus reducing the current risk of wilding conifers to the environment, society and economy.
The project will do this by:
1. Developing a national monitoring and reporting framework for wilding conifers. Establishing and supporting a monitoring network that is cost effective and provides data in a consistent way will allow us to report on the effectiveness of the management of wildings nationally (“Are we winning?”) and will be vital to improve our management (“are we doing it right?”);
2. Conducting a cost analysis for specific wilding conifer control and management regimes based on actual costs incurred in different regions. The cost analyses will allow land owners to realize the full costs of wilding management and what are the most cost effective options for the control of wildings within their land;
3. Understanding wilding Douglas-fir spread better across the wide range of environments and site conditions is needed to make better informed decisions about new Douglas-fir plantings and established forests and how to reduce or prevent spread from these planted estates. Research in this area will focus on understanding factors that affect seed production and establishment and therefore spread risk.
The results and knowledge gained through this project will be used to educate farmers and decision makers via workshops and provide advice and support to community groups and land-managers that are seeking to control and manage wilding conifers. Information will also be shared and disseminated via the NZ WCMG and its website.
This project has three core deliverables:
1. The development of a national monitoring and reporting framework for wilding conifers. A monitoring framework will be developed that enables stakeholders to report consistently on the effect that control and management efforts have on reducing wilding conifers, using nationally developed monitoring guidelines. A key element of this deliverable will be the active support provided to wider stakeholders by the project team to enable them to monitor and report on wildings in a consistent manner. It is suggested that the reporting and monitoring framework and guidelines are transitioned through to MPI ownership/management during the SFF project. The framework and guidelines can be used by MPI to report on progress as they develop and implement an overall Wilding Conifer Strategy in the upcoming year.
This deliverable addresses one of the base underlying needs landowners have by providing them with a way to report the problem of wildings on a consistent basis, in a way that other landowners and government agencies understand. Once populated, the framework for reporting will provide clear evidence on the scale and potential of wilding conifers throughout New Zealand for farmers, land owners and other key stakeholders.
2. Cost analysis for specific wilding conifer control and management regimes based on actual costs incurred in different regions.
A cost analysis of current control methods will be conducted to determine the most effective methods for wilding control based on site conditions and wilding type. The cost analysis will be conducted by collating actual costs from control events across the variety of control techniques(e.g. aerial spraying, stem basal spraying, stem poisoning, chainsaw felling and pulling and cutting ) and terrain and relating these to the conditions and wilding situation (e.g. topography, size and wilding demographics).
The results of the control cost analysis will be translated to all stakeholders and will be put on the NZ WCMG website. The findings will enable individual farmers and land managers to determine the costs for effective control based on the wilding situation, budget size available and land type/area. This will support land managers to make better decisions regarding wilding control options that maximise the long term benefits.
3. Understanding wilding Douglas-fir spread better across the wide range of environments and site conditions. The project aims to improve the existing Decision Support System (Ledgard 2008) developed through the previous WCMG SFF funding, to assess the risk of wilding spread from new Douglas-fir plantings and for assessing the risk of Douglas-fir wilding establishment on high country land. Proposed research on monitoring and understanding Douglas-fir spread and establishment will allow us to develop a better classification of spread prone areas and spread risk sites.
This project focuses strongly on the dissemination of the project results and provision of solid deliverables and outputs to the stakeholder and high country farming community. Information transfer will be achieved through the WCMG website, workshops to inform and educate decision makers, farmers and community groups and our annual WCMG meetings and field trips.
Initiatives to support the wilding conifer strategy
- Written by Thomas Paul