True. Logging is the main threat to old growth forests found in the northwestern united states. Logging is the act of cutting many portion of the forests in order to make place for activities, like livestock or agriculture. It's one of the greatest threat to many forests, including the ones in the northwestern united states. Logging not only threats the forest but us too, by making worse the greenhouse gases effect and by reducing biodiversity. There is also the problem that logging cause the territory to be more unstable, us roots helps the soil against other possible threats.