An Oregon white truffle has a white exterior, which turns brownish orange as it ages. 7. Oregon Black Truffles Larger and less popular than Oregon white truffles, the Oregon blacks emit a strong earthy smell when they are mature. Their exterior and interior are both dark colored. They appear like rough lumps of coal with a texture of ground almonds and moist Parmesan. The most sought-after truffle type, the winter black truffle is loved for its mild earthy aroma and flavor that resembles a mixture of earth and chocolate. It s brownish or grayish black on the outside with white fine veins of the inside. Compared to the winter white truffle, the black variety has a subtler taste that lasts longer. What also makes truffle prices soar is the difficulty of finding and harvesting these mushrooms. Typically, truffles are hunted by dogs and pigs that are specially trained so that they can use their sharp sense of smell to find truffles and to dig them. It didn t help that in 2003, France suffered a heat wave, which took a toll on the living environment of truffles. So it s rather unwise to scour every tree for truffles because you ll just waste your time. For example, you can t find truffles at the roots of a maple tree. Instead, focus your search on oak, hazelnut, fir, beech, hickory, and eucalyptus trees. Soil quality - Truffles are abundant in warm and moist soils. What makes truffle hunting all the more difficult is the fact that this mushroom variety grows underground. You can dig truffles from as deep as 15 inches from the ground. That is why you enlist the help of a trained dog or pig when scouring different sources of truffles in the wild. Your hunting buddy must have the ability to detect the pungent smell of truffles. It is nearly impossible to grow truffles in a greenhouse. Trees are very essential on its growth. Soil - Aside from the trees, it is also important to prepare the soil where the trees would be planted. It has been tested the Mid-Atlantic States have reliable soil types for truffle growth. There are times when the solid has to be amended with lime to adjust its alkaline level.