Definition: The "Colorado fir" is a type of tree that is medium to tall in height. It is found mainly in the central and western regions of the United States. This tree has a narrow, upright shape (like a tall tower) and its wood is soft.
While "Colorado fir" specifically refers to this type of tree, the word "fir" alone can refer to other types of fir trees that grow in different regions.
There are no specific idioms or phrasal verbs related to "Colorado fir" itself, but you might encounter phrases like: - "As tall as a fir," meaning something is very tall, referencing the height of fir trees.