Invasive plants cause environmental harm by spreading uncontrollably and replacing native plants, upon which native wildlife depend. Many of the non-native plants that become invasive here are native to Asia where the climate and other environmental conditions are similar to Louisiana. Plants that become invasive generally produce and disperse an abundance of seeds, grow rapidly, and tolerate a wide range of environmental conditions. Louisiana is more vulnerable than most other states to invasive-species infestations because of its favorable climate. High rates of precipitation; long, hot summers; and short, mild winters enhance the chances that once introduced into Louisiana, non-native species will become established here. These non-native plants also lack the predators and competitors found in their native habitat, so they thrive here in Louisiana and other parts of the U.S.
Attempting to control invasive plants once they become established is costly and time consuming. The annual costs of monitoring and controlling invasive species, and their damage to crops, fisheries, forests, and native wildlife has been estimated to exceed $130 billion in the U.S. alone (Pimentel et al. 2000). A more recent conservative analysis of the data reported that from 1960-2017, the U.S. incurred $1.21 trillion in economic costs from invasive species (Crystal-Ornelas et al. 2021). Preventing potentially invasive, non-native plant species from establishing here in the first place is more cost effective and less environmentally damaging. Once introduced, early detection and a rapid response offers the best chance to successfully eradicate an invasive species.
An effective method of managing invasive plants incorporates a three-pronged attack. First, recognize and remove non-native species. Employ a removal method that minimizes disturbance in the landscape as much as possible. Any disturbance tends to give the upper hand to invasive plants. Second, plant appropriate native species. Third, recognize native plant volunteers and consider keeping them. This approach will place non-native invasive plants under greater stress both by active removal and greater competition from native plants, resulting in a stronger, resilient, self-organizing landscape that may one day be able to hold its own against non-natives.