Root Control Barriers
One of the easiest and most available materials used to control root growth are various types of two-dimensional barriers. There are a number of commercial products on the market, some using a herbicide. In a survey of community management programs, 50% of surveyed programs said barriers are considered at least partially effective (24). Listed by survey in order, after species selection and mechanical cutting, barriers represent a more tree-literate approach to root growth control. But as with most things biological and installed by humans, no barrier is completely effective as applied (43).
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