Phytophthora × cambivora is a plant pathogen that causes ink disease in European chestnut trees. Ink disease, also caused by Phytophthora cinnamomi, is thought to have been present in Europe since the 18th century, and causes chestnut trees to wilt and die; major epidemics occurred during the 19th and 20th centuries. P. cinnamomi and P. × cambivora are now present throughout Europe since the 1990s. Ink disease has resurged, often causing high mortality of trees, particularly in Portugal, Italy, and France. It has also been isolated from a number of different species since the 1990s, including:Golden chinquapin trees, in Oregon, United States Rhododendron and Pieris species in North Carolina Noble fir trees in Norway Beech trees in Italy and Germany.

Castanea sativa, the sweet chestnut, Spanish chestnut or just chestnut, is a species of tree in the family Fagaceae, native to Southern Europe and Asia Minor, and widely cultivated throughout the temperate world. A substantial, long-lived deciduous tree, it produces an edible seed, the chestnut, which has been used in cooking since ancient times.