The Influence of Feral Swine (Sus scrofa L.) Foraging on Redroot (Lachnanthes caroliana Lam.) Growth and Distribution

Abstract

Plants found in Florida wetland ecosystems are accustomed to regular soil disturbances such as fire, animal foraging, and seasonal changes in the hydrologic cycle. Carolina redroot (Lanchnanthes carolinia Lam.) is a perennial herb native to the Eastern United States. Through fragmentation of its distinctive red rhizomes, redroot readily colonizes open patches of soil following disturbances within wetland ecosystems. In Florida, redroot is a weedy species considered to be a nuisance on wetland cattle ranches. The success of redroot colonization in Florida wetlands has been attributed to the presence of the feral swine (Sus scofra L.) who forage for nutrient rich rhizomes. Feral swine are invasive, ecosystem engineers whose foraging technique, known as rooting, overturns large patches of soil, homogenizes soil horizons, and fragments plant rhizomes. The abundant and disruptive nature of feral swine has led to a decrease in plant diversity by promoting monocultures of redroot. The presence of feral swine, and subsequent colonization of redroot poses a threat to cattle ranch management practices. This study examined the relationship between feral swine rooting, redroot growth, and changes in species composition on a Florida wetland cattle ranch.