Is there a recommended spacing when planting new trees so they do not interfere with each other's growth? I want to group a number of the same tree species together as densely as possible while still allowing sufficient sun so they grow almost as if each tree were alone in a field. Essentially, I do not want to create a forest of trunks with leaves only at the top.
Is there simple rule or formula for this? As a made up example: Minimum distance between trees should be 1.5 times the expected height or 2 times the expected crown spread (whichever is larger) for typical trees in the species.
If there is not a general rule of thumb for all species, I would appreciate recommendations for spacing between white dogwoods.