T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Pseudotsuga menziesii (Douglas-fir)

Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Pinaceae
Genus: Pseudotsuga
Species: P. menziesii
Binomial name: Pseudotsuga menziesii
Common name: Douglas-fir, Oregon pine, Blue Douglas fir, Douglas spruce.

Pseudotsuga menziesii is an evergreen conifer species native to western North America. It will grow on banks, clay, dry, gravel, gully, hill, margin, roadside, sand, shaded, sheltered, slope, stone and terrace land.
It is a large or very large tree with horizontal branches and drooping branchlets. twigs are slender, red-brown, with long, sharp, pointed, red-brown buds. The tree's bark is smooth and grey on young stems, becoming thickened, red-brown with ridges and deep furrows.
It produces a highly regarded timber preferred for its superior strength, toughness, durability and decay resistance.

The leaf is an evergreen, single needle which is yellow-green to blue-green in colour and orange-scented when crushed. It is 3.8 cm long with blunt or slightly rounded tips.
The flower is monoecious (having the male and female reproductive organs). The male cones are small (1.2-2 cm long) and are oblong, red to yellow while the females are reddish with long bracts.
The mature female cones appear towards the branch tips and they are not persistent, pendant, symmetrical and are about 4-10 cm long. They have rounded scales. Three-lobed bracts extend beyond the cone scales. Maturing occurs in late summer.

In New Zealand, in some areas, Pseudotsuga menziesii is a problem wilding (uncultivated) pine species, as are Pinus radiata and Pinus contorta. This is due to their seeds being dispersed by the wind, sometimes into tussock grasslands. Wilding pines are a nuisance in areas where native forest does not occur, such as above the bushline, in mineral belts and tussock grasslands. In areas such as these, it creates a major intrusion and modification to natural ecosystems.

In areas where native forest regrowth is being encouraged pines are visually intrusive. They compete for forest space with native trees and plants, but provide none of the advantages these offers, such as berries and nectar, to encourage bird life and insects. Pine needles form a carpet which discourages regeneration of native forest floor species. If nothing is done, the grasslands become pine forest. Small pine seedlings can be pulled out by hand, but larger trees need to be felled and their stumps coated with herbicide.

A commercial plantation. Nelson area.

A wild sapling  (wilding) growing on the roadside.

The needles (leaves)

Open seed cones.

Open seed cones.

Photo showing how wilding pines can self-spread over a hillside in the Wakatipu area. (Species unknown)

Extreme wilding pine control video filmed at Kaweka Forest Park.
This 4-minute clip on TVNZ video player video shows how DOC staff hang from a chopper to remove wilding pine trees.

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/