Picture Dorchester County as a jigsaw puzzle. And picture the all-green pieces stretching along the 40-mile-long Four Holes Swamp. What you're picturing is a conservation dream that looks more doable than ever.

Here's why: Last year, Norfolk Southern put its 12,000-acre Brosnan Forest under conservation easement. Private landowners, who had been skeptical of such easements, took note.

Since then, the Lowountry Open Land Trust has been busy responding to private property owners. It has sewn up three easements totaling 400 acres, and it has received inquiries from at least 50 more people who own land in the areas targeted for conservation.

Land Trust Executive Director Will Haynie compares the groundswell of interest to landowners' enthusiasm for preserving the ACE Basin, which has been a tremendous boon to the natural Lowcountry.

Dorchester County and its residents have made commendable strides in planning. Dorchester's Comprehensive Plan supports the preservation of rural areas and green space. Conservation progress at Four Holes Swamp moves the county closer to its goals.

Dorchester County also can provide inspiration for neighboring Berkeley and Colleton counties to adopt plans that will define how and where they should grow and where they should protect the environment as it stands. While Colleton is not yet threatened by too much development, Berkeley faces various challenges that are associated with growth.

Coastal South Carolina's conservation successes, including Four Holes Swamp, mark a welcome break in the long chain of development on and near the coast that stretches from the North to the South, from Boston to Miami.

That is good news for local wildlife and for water quality. It is good news for ecotourism.

And it is very good news for the future of South Carolina that more and more citizens are learning to value conservation and land planning.