Purpose: To provide air, water and fertilizing ports in the root area of trees that have paving over their root zones. Their main value is to vent toxic gases to the surface and to allow oxygen to enter the soil under the paving. Their secondary value is for water and fertilization. Fertilizer should be applied through the vents annually.
Procedure: Vents can be installed at 6 feet on center to about 10 feet on center. The inner circle is established about 6 feet from exposed soil. The outer circle follows the branch spread of the tree. Interior circles are spaced between these two circles at the chosen spacing distance. A rock drill with a 2.5 inch star bit is used to drill through the paving and base material into the original soil. If paving is concrete, it requires the appropriate drill. The vent sleeve is driven through the pavement and base into the original soil and the vent top is placed in the sleeve. The top will eventually become recessed to grade in asphalt and gravel. It will rest on top of concrete and pavers.