Only if the trees are allowed to burn or rot. If they're cut down and turned into lumber and paper, the CO2 won't be released (for a very long time, if ever), and, in addition, if new trees are planted in the same areas, even MORE CO2 will be taken up than the entire older forest (young, growing trees take up far more CO2 than mature forest trees).
Do you think the environmentalists will allow the trees to be used for something useful? With the CO2 hysteria, perhaps the left and their rat allies can be persuaded to harvest the infested trees. Given past restrictions, I am not optimistic.