Castellated chemically coated seedling box

Abstract From the Canadian patent

Disclosed is a unique tree seedling container constructed from expanded polystyrene, rectangular in shape and haing cavities moulded therein. The cavities are tapered from top to bottom and are open ended. The inner cavity walls are constructed in a castellated form having one or more raised portions extending vertically downwards the entire depth of the cavity. Grooved portions intersperse the raised castellated portions. Either one or the other of the grooved or raised portions is coated with a chemical, to prune the lateral roots of a tree seedling which come into contact therewith.