Corylus colurna (Turkish Filbert or Turkish Hazel)
This species, native to Turkey and surrounding areas, is extremely resistant to Eastern Filbert Blight. Unlike the shrubbier C. avellana (European Filbert), C. colurna produces a single-stem tree with an upright, pyramidal shape. This host thrives in hot summers and cold winters. It is also extremely drought tolerant once established. USDA zones 5-7 are acceptable for this host tree.
Pseudotsuga menziesii (Douglas Fir)
This conifer in the Pine family, though not a true fir, is a unique species unto its own. The Latin name means simply “false hemlock”. The Douglas Fir is an excellent, proven host for Leucangium carthusianum (the Chartreuse or Oregon Black Truffle). This stately tree is an excellent choice for orchards in cooler climates that wish to offer another superb truffle species. However, it is not particularly drought or wind tolerant. It may also struggle in the heat of zones 8 and warmer.
Quercus ilex ssp. ilex (Holly Oak)
Quercus ilex, an evergreen oak species, is the common host tree in Spain and other truffle-producing areas. While it is happiest in Mediterranean climates, Q. ilex does remarkably well in the Southeastern United States. Cold hardiness is an issue with this species, as it will struggle in USDA zones 6 or colder; significant damage occurs from the cold in Zone 7 in some years. Surprisingly, it has been promoted and sold by our competition in areas where it simply cannot tolerate the cold temperatures. Best suited for Zones 8 and warmer.
Quercus ilex ssp. rotundifolia (Roundleaf Holly Oak)
A subspecies of Holly Oak, Q. ilex rotundifolia is a relatively unknown tree in the United States. However, it is much more cold hardy than Q. ilex ssp. ilex, which is the typical species offered in the United States. In its’ native range, it is found at higher elevations than Q. ilex ssp. ilex, and will perform far better in marginal climates. Due to the limitations of Quercus ilex ssp. ilex, we offer this highly productive truffle host to our northern customers; cold consistently damages and kills Q. ilex ssp. ilex. If you are in zone 7 or colder, insist on this subspecies if you choose to grow Quercus ilex. We cannot exaggerate the quality of this host tree!