I bought a house on 1.5 acres about 2 years ago, and by the time I got there, all of the large ash trees were killed off by emerald ash borer. I'd say there were 5 really large ashes that have already fallen or are dead and bound to fall soon. After clearing out an enormous amount of honeysuckle, I stumbled upon hundreds of baby ash trees less than a foot tall. And then at least a couple dozen ash trees about 5 feet tall. And then maybe about 5 ash trees a few inches in diameter. So, a lot of ash trees. Getting to my question, should I really let these trees grow up? I know I'll have to pull some of them since they're growing right on top of each other, but I know emerald ash borer is in this area, it's already killed off ash on the property, so they seemed doomed to die and become an expensive liability if I leave them. Any advice?
I was in a similar situation a few years ago. I chose to remove the trees as I had free time during the growing season. My thought-process was that if I left the small trees to grow up, then when they die it would be a lot harder (and potentially expensive) to remove them. If you cut each tree near the base of the trunk and apply a coating of Triclopyr you will kill the tree pretty efficiently. I'm not usually a big fan of pesticides, but after trying to manually remove hundreds of honeysuckle and buckthorn and nearly destroying my back and hip in the process, I've become a fan of Triclopyr for this purpose. (this advice depends on your location, as Triclopyr is apparently only easily available in the US).