Pyrus calleryana, Decne, `Aristocrat'; Cryptomeria japonica, D. Don; Populus maximowiczii, Henry × `Androscoggin' and Koelreuteria bipinnata, Franch. trees were grown in low-profile containers. The optimum height and width of these containers was 20 to 30 cm and 84 cm, respectively. Pine bark and mixtures containing 50% or more of pine bark were preferable to mixtures containing leaf mold for filling the containers because the former weigh less. Roots penetrated pine bark mixtures better than sphagnum peat mixtures and also retained their shape better during transplanting. When grown in low-profile containers, trees grew fibrous root systems; after transplanting, roots grew downwardly radial and trees were able to withstand extremely difficult landscape conditions.
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