State Rep. Stan McClain has filed a bill to buy 65 acres of citrus groves for Marion County to benefit Lake Weir.

The $3.6 million purchase would become part of the Carney Island Recreation and Conservation Area.

Ocklawaha Groves is on the western shore of Lake Weir. Its rows of citrus trees are surrounded on three sides by the county park. The proposed acquisition includes 65 of the property’s overall 85 acres.

Reese Bourgeois, president of the nonprofit Save Lake Weir, says fertilizer used in agriculture — and on landscaping for homes — is one of the major contributors to the lake’s decline. Septic tanks are also a big problem.

“There’s been dramatic increases in nitrogen and phosphate levels in the lake,” he said, “and over the last 15 to 20 years, significant decline, also a significant decline over the 30 to 40 years, if you talk to experienced fisherman, in the size of the fish and the healthiness of the fish”

The land is up for sale, and Marion County parks director Jim Couillard says the purchase would remove the potential for more septic systems near the lake.

“It makes good sense for the benefit of the lake,” he said. “It also makes good sense for the benefit of the park and the park-users.”

Marion County would return the land to its natural pines and hardwoods and create opportunities for hiking and camping.