Truffles are found all over the world and are usually associated with certain families of trees such as Pine, Oak, Hazelnut and Willow; although almost any tree can form mycorrhizae with truffle forming fungi of some kind.
Depending on the species of truffle and environmental conditions they can be found erupting through the soil or up to 12 inches (or more!) underground.
In the Pacific Northwest region of North America, three of the commercial culinary varieties of truffles grow in association with Douglas Fir (Pseudotsuga menziesii) in coastal forests and timber stands. The main growing season for commercial culinary species in the Pacific Northwest is winter through late spring. Different species of truffles, such as some of those in Europe will be ripe at different times of the year.
