The roots of oak or hazelnut saplings are inoculated with truffle spores and then planted. Hazelnut trees are most commonly used to cultivate truffles. The tree will produce nuts above ground, and you can also harvest truffle below the surface.
Oak trees have also been used successfully and some researchers have suggested citrus trees such as Orange may also make an excellent host tree.
To get started, clear an area of competing vegetation, trees, brush and weeds. Soil pH is extremely important . Acceptable soil pH range is between 7.5 and 8.3, 7.9 is optimal. Add lime to the soil if it is acid. [See Measuring and Adjusting Soil pH in Gardens]
The host tree must have an extensive root system before the truffle can be produced . You can also interplant other crops , such as grasses and annual herbs while the truffle orchard is being established , however once established truffles emit a compound that inhibits the growth of other plants.
French truffles do best in slightly alkaline gravelly soil. In the gravelly soil the truffle’s root system will develop horizontally, parallel to the surface, and the and necessary root-fungus relationship is firmly established. Truffles grow near tree roots.
Historically, truffle hunters used pigs or dogs to find their prized truffles. With only a few trees, searching by hand is not a difficult task. Look for a natural dieback of weeds and grasses around the tree. Mature truffles emit a compound that kills vegetation on the surface where it's growing.
The 2 largest Suppliers of Inoculated Truffle Trees in the USA are
Garland Truffles New World Truffieres
Taming the Truffle: The History, Lore, and Science of the Ultimate Mushroom