Growth response of two red maple cultivars (Acer rubrum L. `October Glory' and `Northwood') to styrene lining or copper hydroxide coating of 23.3-liter black plastic containers was evaluated. After the first growing season, plants were left in their original container, repotted into 51.2-liter nontreated containers, or transplanted into the landscape. Copper hydroxide effectively reduced circling of roots of both cultivars at the medium–container interface during the first year of production, but was less effective during the second growing season. Repotting from copper-treated containers into 51.2-liter containers or transplanting into the landscape resulted in more fibrous root development and enhanced root regeneration outside the original rootball relative to transplanting from nontreated containers. However, when copper hydroxide was applied to styrene lining, root regeneration after transplanting was reduced. Roots of plants grown in styrene-lined containers covered the medium–container interface more thoroughly than those in nonlined containers, but height, trunk diameter, and root regeneration were similar. `October Glory' had a larger trunk diameter, more branching, and better root regeneration than `Northwood'.