Important Update:

A new DSS to calculate wilding spread risk from new plantings (DSS1) has been developed by Nick Ledgard (former manager of the WCMG) for the proposed National Environmental Standards for Plantation Forestry (NES) as part of a contract for the Ministry for the Environment.

"Wilding tree risk was identified during the scoping of the proposed National Environmental Standard for Plantation Forestry as being a particular risk that should be addressed in the proposal. In 2011, the Ministry for the Environment set up a working group made up of key stakeholders from Ministry of Primary Industry, SCION, Department of Conservation, Local Government New Zealand, the forestry sector and Environment and Conservation Organisations of Aotearoa. This group gave advice on how wilding tree policy could be incorporated into the proposal.

A wilding tree risk calculator (DSS1) was created. This involved adapting a calculator that was already established by the New Zealand Wilding Conifer Management Group. The main purpose of the calculator is to inform decision makers of the risks of wilding trees from new forestry plantings due to species type, location, surrounding land uses and vegetation cover. "(Rachel Fyffe; Background statement from the Ministry for the Environment, June 2012)

The new DSS is available here (click to view and download) and will replace the older versions of the DSS Calculator for wilding spread risk from new plantings, which are still accessible via the download of the booklet and a previous report (see below).



It is important that land owners wishing to establish new plantations of conifers are aware of any potential for the unwanted spread of wildings before they start planting - particularly relative to to wildings, which may spread outside the boundary of the plantation managed area.


For this reason, a short, easy to read 'wilding prevention' booklet was prepared in 1999. This outlines the major factors influencing wilding establishment and the means by which managers can avoid or mitigate the risk of spread. Many local governments in spread susceptible areas now require prospective tree planters to consult this booklet before planting trees. The booklet can be ordered from Nick Ledgard, SCION Christchurch or can NOW be download as a pdf by clicking here

The booklet includes a decision support system (DSS) for assessing risk from new plantings (now replaced by the new DSS1 above (see important update). A second DSS (DSSb) has been produced for calculating the risk of wilding tree spread into/ withhin new sites.

A report 'Assessing risk of wilding spread ' has been written on DSSa and DSSb (click here to view it) - this includes risk assessment forms for both (older versions). There is also an electronic interactive version of this older DSS, which can be used by clicking the following link:

Wilding Prevention Decision Support System


Wilding Control

A second user-friendly handbook is now been prepared as part of the SFF Wilding Project on 'wilding control' (objective 2, Milestone 4). It contains a list of all the methods currently employed for controlling wildings, plus a DSS to assist land managers to select the technique most appropriate for their situation. To download the booklet as a pdf please click here: