Pine, Radiata

(Also known as Monterey Pine)

Pinus radiata

Family: Pinaceae

Type of weed: Woody weed

Description

A very fast growing tree up to 50 m tall. The bark is thick and furrowed.

Leaves are linear, pine-like and arranged in groups of three; they are aromatic when crushed.

Male and female cones are produced on the same plant. Male cones are small and yellowish. Female cones are soft and purplish at first, ripening over 18–36 months to form 7–15 cm brown pine cones.

Dispersal

Radiata Pine has been widely planted for forestry and windbreaks. It is highly invasive usually in areas where the rainfall exceeds 600 mm. Seed is dispersed long distances by wind. The Yellow-Tailed Black Cockatoo uses the seed as a food source and spreads the seed further into bushland.

Impact on bushland

Pines reduce the fertility of soils, alter the nutrient and water cycles, reduce light levels and generate thick layers of pine needles that prevent seed regeneration and growth of seedlings. Radiata Pines form dense stands that shade or crowd out most native trees, eventually creating monocultures.

Radiata Pines attract other bird dispersed cool climate weeds such as Holly, prunus species, Privets, Ivy and Berberis.

Distribution

Lower Blue Mountains, Upper Blue Mountains. Mid to Upper Mountains.

Alternative planting

Native plants

Choose from local native plants such as:

Hakea spp,
Banksia spp,
Petrophile spp.
Isopogon spp,
Mueller’s Cypress Pine (Callitris muelleri)
She Oaks (Allocasuarina littoralis)

Council provides a tool, on its Mountain Landscapes website, to help you choose native alternative plantings. Choose your village, soil, vegetation community and the purpose of your planting, and the tool will give you suggestions.

There are native nurseries in several Blue Mountains villages, including Glenbrook, Lawson and Katoomba. Please also ask at your favourite local nursery.

Control

Hand remove
Chop down
Stem inject or frill

Manual control

Hand remove

Grasp stem at ground level. Rock weed backwards and forwards to loosen roots, then pull out gently. Carefully tap the roots to dislodge attached soil. Replace disturbed soil and pat down.

Considerations

Leave weeds so that roots do not make contact with soil; on a rock, for instance. A small amount of debris may be hung in a tree or removed from the site.
Vary the position of your body to avoid fatigue when removing plants by hand over extended periods.

Cut down (fell)

Some trees, like radiata pine, may simply be cut down. Others may need follow-up treatment. See specific notes below to check.

Chemical control

Note: Herbicides that may be used for this weed include Glyphosate.

Stem injection or frilling

Stem injection

Drilling holes at 45° and squirting poison into holes — Apply poison immediately after drilling

At the base of the tree, drill holes at a 45° angle into the sapwood (just under the outer bark) at two finger space intervals around the entire base of the tree. Repeat this process below the lowest branch

Frilling

As an alternative to drilling, make cuts into the sapwood with a chisel or axe. Fill each cut/hole with herbicide immediately. Repeat the process at 3 cm intervals around the tree.

Considerations

Plants should be healthy and actively growing. Deciduous plants should be treated in spring and autumn when leaves are fully formed. For multi-stemmed plants, inject or chip below the lowest branch or treat each stem individually. Herbicide must be injected immediately before the plant cells close (within 30 seconds before translocation of herbicide ceases.)