Six more live oak trees eventually will become part of the canopy over Johns Island roads.

Charleston County planted the trees Thursday along Bohicket and River roads and the Betsy Kerrison Parkway. They are now approximately 4 inches in diameter, but will grow over the next 20 to 25 years to become part of the canopy over the island's scenic highways, said Joel Evans, a county planner and landscape architect.

The young trees will replace six trees that were between 50 and 100 years old but had to be cut down because they were in poor health and posed a safety hazard. Replacing the trees was important because it "keeps the canopy in place for future generations," Evan said. "That's what it's all about."

He thinks the trees will fare well because live oaks are native to the Lowcountry.

The trees cost about $600 each, which included planting and watering them for a year, he said. "We need to give them every chance to establish themselves."

Money for the trees came from the county's Tree Fund, which is used to plant and replace trees countywide. Money in the fund, which was established more than a decade ago, comes from contributions for tree mitigation, or contributions paid when people legally remove trees. It also comes from tree protection and preservation violation fines. Evans said the county has spent about $120,000 replacing trees over the past six years. About $150,000 remains in the fund, which is used exclusively for planting trees on public land.

Reach Diane Knich at 937-5491.