Outlook from hillside with wilding pine in foreground Outlook from hillside with wilding pine in foreground

    Wilding Conifers

    Know Your Species

    Not all conifers are a problem. The Upper Clutha Wilding Tree Group targets those conifers where growth gets out of control in our unique climate and soil conditions.

    The most common wilding conifer species in our area are:


    (Pseudotsuga menziesii)

    Our region’s most common wilding conifer with light wind-blown seeds that travel for many kilometres. Flat, soft needles, pale on underside. Distinctive three-pronged scales on cones.

    Radiata Pine

    (Pinus radiata)

    The most commonly-planted pine in NZ that is often used for forestry. Dark green needles 9-13 cm long. Cones 7-15 cm long.

    Contorta/Lodgepole Pine

    (Pinus contorta)

    Needles dark green to yellow green, 4-7 cm long. Cones 3-6 cm long, their scales end in distinctive, slender prickles. Cones retained on tree. Once established, it’s hard to control.

    Black Corsican Pine

    (Pinus nigra)

    Needles grey-green or bluish-green, grooved on opposing sides of the pair 8-16 cm long (occasionally three needles). Cones 5-8 cm long,
    scales end in minute prickles. Cones annually.

    European Larch

    (Larix decidua)

    The most common larch species. Deciduous. Once established, it spreads easily around Wanaka and Hawea.

    Wilding pine spread on hillside Wilding pine spread on hillside

    Our Strategy

    How we do it:

    • Alert

      The community to the exponential spread and cost of wilding control

    • Communicate

      The Upper Clutha Wilding Tree Group programme of control and projected effects of no control

    • Eradicate

      ALL seeding trees where possible

    • Contain

      Non-removable wilding areas and planted forests

    Operational Work

    All trees are GPS marked before removal and added to the extensive National Mapping Programme. The mapping of current and historical control helps to shape future priority work.

    The National Wilding Conifer Control Programme, coordinated by MPI, researches control methods and develops guidelines for best practice. These summarise standards expected for safe wilding conifer control.

    Cut Stump Ground Control 

    Cut stump is a control method that involves cutting a tree down and applying herbicide to the cut stump to prevent regrowth. It is suitable for the control of trees which are accessible from the ground and where the risk of damage to surrounding vegetation is minimal or not a concern.

    Drill and Fill

    Ground-Based Herbicide Injection

    Drill & Fill can be a very cost-effective method where trees have a trunk diameter of over 10cm and are accessible to ground crews.

    Rather than cutting down large trees, it is often better to drill holes into a tree’s trunk and fill the holes with herbicide.

    This is a good option on difficult terrain where felling is unsafe.

    ABBA Aerial Basal Bark Application (Lancing or Wanding) 

    Lancing is a type of aerial spot spraying used to treat individual trees/noxious weeds by using “Basal Bark mixture” applied by hand using the helicopter as an operational platform to ‘Chemically Ringbark’ tree trunks via a lance in a manner that wets the complete circumference of the trunk or lower stems. Most trees controlled in this way are small, and the “chemical ringbark” action is applied directly to the stem only and not the whole foliage. The release height above the tree is a matter of centimetres hence the overall herbicide use is more accurate and in considerably lower volumes than what most public perceive about aerial spraying. Spray drift from this product and application method is extremely low. A passenger crew person inside the helicopter sits holding the “lance” and applies the herbicide as the helicopter is piloted in a hover directly over the plant.

    The ABBA method is particularly useful for widely scattered trees, inaccessible or unsafe areas (such as steep slopes) and in sensitive areas where specific targeting of wilding conifers is required amongst desirable vegetation or public assets.

    Dead trees are left standing until they naturally rot away. It is the most efficient way to control scattered wildings in difficult-access areas or within high-value vegetation.

    Aerial Foliar Spray Application: (Boom spraying)

    As a last resort in dense and inaccessible wilding stands, helicopters are used to deliver herbicides known as Aerial Foliar Spray Application (AFSA).

    AFSA is only used in ideal conditions to ensure the operation is precise and well away from waterways.

    AFSA Boom Spraying is a cost-effective approach that treats large dense infestations. It is best used where there is minimal risk of damage to nearby vegetation.

    Over time, the dead trees will decompose into the soil.