Points of Interest:
- An unusual sinkhole pond marsh that provides important habitat for amphibians and rare plants.
- A contrasting habitat to the surrounding dry oak-pine woods.
Natural Features Description: Sinkholes are formed from the collapse of an underground cavity or the slow dissolution of underlying calcareous bedrock. Sinkhole ponds form when the bed of a sinkhole is lined with impermeable clay and organic matter deposits that prevent water from draining. This sinkhole pond is typically wet in the winter and spring but often dries up in the summer and fall. Amphibian species such as spring peepers, gray treefrogs, spotted salamanders and American toads utilize these seasonal wetlands for raising their young. Interestingly sinkhole ponds in the Ozarks harbor wetland plant species more typically found in the southeast coastal plain. For example, epiphytic sedge, found in this pond more commonly grows on the bases of cypress trees in swamps. Marg pond is one of the shallowest sinkhole ponds which still contains a high-quality herbaceous dominated marsh. The edge of the pond is clothed in a dense mat of sphagnum moss.
This natural area is within the Mark Twain National Forest. From Winona, take Highway 60 east about 4 miles to Shannon Co. Road 60-A. Turn left (north) and travel 0.5 mile. Marg Pond is to the west of the road. Hunting is permitted.