Goal: Sustain Our Nation’s Forests and Grasslands Plant community inventory of the South Fourche Botanical Area in Arkansas ends with a twist

A steep glade along the South Fourche LaFave River houses a number of rare plants in the South Fourche Botanical Area. (Forest Service photo by Virginia McDaniel)

Introduction

Botanical inventories help describe natural areas and are useful in documenting the ranges and distributions of rare and common native species as well as non-native and invasive species. Understanding these distributions is important to the conservation of rare plants and the control of non-native plants. Forest Service researchers have spent five years inventorying a special place, the South Fourche Botanical Area, Arkansas. This spring, an SRS researcher found a plant endemic to the Ouachita Mountains here, extending its narrow range by over 50 miles.

Summary

The Ouachita Mountains in Arkansas are home to a number of endemic plant species, many of which are found only in glades, barrens, open woodlands, and river scour-prairies.

The South Fourche Botanical Area was designated by the Ouachita National Forest in 2005 because of its unique plant communities, including a hanging oxbow, a salt lick, and several groundwater seepage areas, as well as some high-quality glades, woodlands, and river scour-prairies.

In 2016, Forest Service researchers began a full inventory of the plant diversity of the area. Botanists from the state of Arkansas and The Nature Conservancy joined the effort. Researchers identified eight community types and tallied nearly 700 plant species, including 13 of conservation concern in Arkansas.

Because of the survey, more than 100 new species have been added for the county where this area is located. The Ouachita twistflower (Streptanthus squamiformis), previously thought to be limited to portions of three counties in western Arkansas, was found at the South Fourche Botanical area—a 50 mile range extension for a species whose range was only ~30 miles wide!

Principal Investigator: Virginia McDaniel, Forestry Technician
RWU: 4159 - Southern Pine Ecology and Management
Strategic Program Area: Inventory and Monitoring
External Partners: Susan Hooks - Ouachita National Forest; Theo Witsell - Arkansas Natural Heritage Commission; Brent Baker - Arkansas Natural Heritage Commission; Doug Zollner - The Nature Conservancy