On the coasts, it is associated with western hemlock and other conifers.īigcone Douglas-fir (P. On the west side of the Cascades and Sierra Nevada, it is often the predominate species, but usually occurs in conjunction with several other confers. It grows under a wide variety of environments from extremely dry, low elevation sites to moist sites. The entire range includes central California, western Oregon and Washington, parts of the Rockies and extends north to Alaska. The cones open in the late summer to disperse the seeds and will continue to hang on the trees through the fall. They are reddish-brown to gray, 3″ long and do not dissipate to spread seed as do true firs (Abies sp.). Young cones are small, oval shaped and hang downward. Pollen strobili are small and reddish-brown. They have a sweet fragrance when crushed. The needles are dark green or blue green, 1 to 1 1/2 inches long, soft to the touch and radiate out in all directions from the branch. The branches are spreading to drooping, the buds sharply pointed and the bark is very thick, fluted, ridged, rough and dark brown. This wide ranging species grows from 70 to 250 feet tall.
They are one of the top major Christmas tree species in the U.S.ĭouglas-fir is not related to the true firs. When crushed, these needles have a sweet fragrance. The douglas fir needles radiate in all directions from the branch. Spray (spring-summer): glyphosate (100ml/10L) or metsulfuron-methyl 600g/kg (5g/10L) What can I do to stop it coming back?Ĭontinue to monitor and remove further infestations as seedlings appear.These soft needles are dark green – blue green in color and are approximately 1 – 1 ½ in. Immediately apply metsulfuron-methyl 600g/kg (1g/L) to each cut using a paintbrush or squeeze bottle.ħ. Frilling (all year round): with a sharp chisel or axe, make a deep cut into the sapwood at regular intervals around the base of the tree, taking care not to ring-bark the plant. Cut and squirt (all year round): make one cut every 150 mm around the trunk, and fill with 1g metsulfuron-methyl 600g/kg per cut.Ħ. Bore & fill (all year round): drill 1 hole every 150 mm around the trunk, and fill with 1g metsulfuron-methyl 600g/kg per hole.ĥ. Don't need to remove all green needles if using this method.Ĥ. Stump swab (all year round): cut down close to ground and paint stump with metsulfuron-methyl 600g/kg (1g/L) or picloram gel. Cut down (all year round): cut low enough to remove all green needles. Handpull small seedlings (all year round). Found in scrub and forest margin communities, shrublands, tussockland and light wells in forest. Lowland, montane and subalpine habitats, growing in sites with low-moderate fertility. Major wilding conifer species in southern areas. Can also threaten landscape character and recreation value. Invasion and suppression of grassland and regenerating shrubland, invasion of low-stature plant communities including herbfield and tussockland. Seldom spreads onto land where vegetation cover is dense. Seed is spread by wind in autumn and winter, with seedlings establishing most readily on well lit sheltered sites where there is no competition from other vegetation. Can change landscapes completely, threatening fragile grassland and herbfield ecosystems.
Produces up to 20,000 wind-spread seeds per tree every year, and seed can remain viable for years. Rapidly invades high country land, costing millions a year to control. Seed scales are large and broad, bract scales are longer and thinner than seed scales, and are 3-pointed, with the centre point longest. Male cones (12-20 mm long) are catkin-like, while papery cylinder-shaped female cones (5-10 cm long) are downward-pointing. Needle-like leaves (15-38 x 1-2 mm) are clustered in twos, whitish beneath, have edges that are often rolled, and are orange-scented when crushed. Shiny purplish-brown winter buds (to 1 cm long) are narrow and sharp. Ridged shoots are light to dark brown with short hairs. Branches sit horizontally, and are in irregular whorls, while branchlets usually droop. Very large resinous evergreen tree with thick bark that is reddish-brown underneath, and rough and furrowed when mature. Pinaceae (pine) Where is it originally from?
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