91448
Problematic exotic disease introductions in the past century or so include the chestnut blight which has almost eliminated the American chestnut tree from its forest habitat .
 chestnut blight, American chestnut
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 chestnut blight, American chestnut