American Chestnut blight

I have 3 American chestnut (Castanea dentate) here on my property in midcoast Maine. My guess is they are about 20 years old, planted sometime in the mid to late nineties by the original owner. They fruit each year but I've seen almost no edible chestnuts. What I have also noticed is one of them which has taken a beaten over the past few years still hasn't lost its leaves and its February. The other, has seemed to die back on the southern side and I can see some mushroom growth along the trunk. This all makes me feel they are dealing with blight and my question for you is what to do? Is it best to just cut the trees down?

I would contact the American Chestnut Foundation for advice on that. The contact email for the Maine chapter is Mainetacf@gmail.com