Eastern White Cedar hedge spacing
I spontaneously bought 40 3 feet high Eastern White Cedar trees to plant along my 70 feet long chain fence. Since I am novice gardener soon after the purchase I started to do research on how to best plant it which brought me to this great forum.
I read varying opinions regarding the spacing. One expert suggested that the trees should be planted as closely as possible ("root ball to root ball") while others said that trees should be minimum 3 to 6 feet apart.
I'd like my hedge to be thick and not too high - 12 feet at the most so I can prune the tops off. How close should the trees be from each other? Would 40 trees be too much to cover roughly 70 feet in length?