David Douglas was a Scottish botanist, best known as the namesake of the Douglas fir. He worked as a gardener, and explored the Scottish Highlands, North America, and Hawaii, where he died. The standard author abbreviation Douglas is used to indicate this person as the author when citing a botanical name.

The Douglas fir is an evergreen conifer species in the pine family, Pinaceae. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three varieties: coast Douglas-fir, Rocky Mountain Douglas-fir and Mexican Douglas-fir.