Your Ph is good, mine runs 4.5 -5.0 in these areas. The land is old farm land that was very over worked and with very little put back in. Invasive species could be a problem, but we already have Austrian pine growing "wild" on parts of the land. The reason we want to introduce Norway spruce is because it matures at a taller height, and will provide a second tree type to the austrian pine. We are planting in a 3:1 Ratio - Austrian Pine:Norway spruce,