Douglas-fir
From CreationWiki, the encyclopedia of creation science
| Douglas-fir |
|---|
|
| Scientific Classification |
|
| Species |
|
|
There are five species of Douglas-fir, two in the Western part of North America, one in Mexico, and two in Eastern Asia. The douglas-firs gave 19th century botanists problems because they were very similar to other trees. The tree was named after David Douglas, a Scottish botanist who first introduced the tree into cultivation in 1826. The existing known Douglas-firs are: the Coast Douglas-fir, Mexican Douglas-fir, Bigcone Douglas-fir, Japanese Douglas-fir, and Chinese Douglas-fir.
Contents |
Anatomy
Douglas-Fir grows 40 to 60 feet and spreads 15 to 25 feet in an erect pyramid. It grows to more than 200 feet tall in its native habitat in the West. Hardiness varies with seed source.
Reproduction
The mature female seed cones are pendent, 4-7 cm long (2 cm broad when closed) opening to 3-4 cm broad. They are produced in spring, are are purple (sometimes green) at first, maturing orange-brown in the autumn 5-7 months later. The seeds are 5-6 mm long and 3-4 mm broad, with a 12-15 mm wing. The male cones are 2-3 cm long, dispersing yellow pollen in spring. Seed is produced annually except for about 1 year in any 4-to-5-year period. The age at first reproduction is 12 to 15 years.
Ecology
The Douglas-fir grows on a variety of sites across its wide geographic range. It grows at lower elevations adjacent to and within bunchgrass communities and is also found in upper elevation subalpine forests. It tends to be most abundant in low and middle elevation forests, where it grows over a wide range of aspects, slopes, landforms, and soils.
Gallery
 Coast Douglas-fir Pseudotsuga menziesii |
 Rocky Mountain Douglas-fir Pseudotsuga menziesii |
 Bigcone Douglas-fir Pseudotsuga macrocarpa |
