I have several different conifers in my yard and I am wondering how deep their roots go. The reason I am asking is that I had an occassion to replace a piece of a sprinkler system and found tonnes of little roots from an Emerald Green arbor vitae around the sprinkler head. The conifers I have are: Arbor Vitae (Emerald Green and Tom Thumb) Berckman's Golden Dwarf Arbor Vitae (not a Thuja sp.) Colorado Blue Spruce Mugho Pine I am thinking about maybe getting either some Leyland Cypress or Arizona Cypress for a hedge. How deep would their roots go?