The optimal truffle habitats are valleys and wooded areas with many oak, beech, poplar, willow and elm trees, but not necessarily forests. Truffles thrive near watercourses, especially those where earthen material is washed up from the watercourse bed. If there are aforementioned species of trees on the banks or in the immediate vicinity, around which the watercourse washes up fluvial deposits to form small mounds, then those are the optimal conditions for the development of truffles.