I'm growing in a climate with a short growing season that gets very cold in the winter, and trees don't really grow as fast as they do in warmer places. I have seen others plant their infestation phase trees at 1m apart in the row, but I'm thinking I should plant at every 30cm or 50cm, and for cost efficiency mostly use willows and balsam poplars which I have basically unlimited access to cuttings for. Would I run into issues at such a high density if I chose to prune and coppice most of the trees after 3 or 4 years so I can start planting my stabilization phase trees, or is it fine to plant an extremely high density?