A total of 28 tropical Amazon woods – many of them rarely used – from Tapajós National Forest, Pará state, Brazil, were tested for their natural resistance against the decay fungi: Ganoderma applanatum , Trametes versicolor , Pycnoporus sanguineus , Meruliporia incrassata , and Gloeophyllum trabeum . The wood resistance classification was made according to the ASTM D 2017-81 method. High variability on susceptibility to wood decay fungi was found. Their mean weight losses varied from 0.6% to 45.6%. Highly resistant species include: Astronium gracile , Bagassa guianensis , Caryocar villosum , Claricia racemosa , Diplotropis purpurea , Dipteryx odorata , Hymenaea courbaril , Manilkara huberi , Mezilaurus itauba , Sextonia rubra , Tabebuia incana, and Vatairea paraensis . The following wood species are less durable: Brosimum parinarioides , Jacaranda copaia , Laetia procera , Pouteria pachycarpa , Virola caducifolia , and Trattinnickia rhoifolia . Meruliporia incrassata caused extensive weight losses in most of the investigated Amazon wood species.