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?

Recently viewed the regrowth on the two year old rows that you cut early spring and it resonated with me, we're much further north,but this year's growth is exceptional and has me quite excited.