Gary N. Ervin
Plant Ecology Lab ~ Aquatic Botany, Invasive Species, Wetland Ecology
Department of Biological Sciences, Mississippi State University
Aquatic vegetation management to enhance multiple-user benefits of southeastern wetlands
Gary Ervin, lead PI
Gray Turnage, co-PI, MSU Geosystems Research Institute
Sam Schmid, doctoral student
Adrian Lazaro-Lobo (former doctoral student)
Our current work in this area, underway as part of Sam Schmid's dissertation research, is examining ecological interactions between the aquatic invasive Alternanthera philoxeroides (alligatorweed) and an introduced biocontrol agent, Amynothrips andersoni (alligatorweed thrips). The goal of that work is to determine whether there is potential to employ integrated control approaches for alligatorweed that combine this insect with known chemical control methods, to more efficiently manage this commonly abundant aquatic weed.
Earlier portions of this work were funded by the MS Water Resources Research Institute. In that work, we explored a variety of chemical control measures (herbicides) to reduce the abundance of key nuisance plant species, while maintaining diversity of desirable species and also minimizing any negative impacts on key water quality parameters (e.g., dissolved oxygen, nitrogen, and phosphorus).
The ultimate objectives of our work in this area is to discover methods to optimally control nuisance aquatic vegetation in wetland and aquatic habitats of areas like the nearby Sam D. Hamilton Noxubee National Wildlife Refuge (NNWR), while minimizing impacts on non-target vegetation and water quality.
Lázaro-Lobo, A. and G. N. Ervin. 2021. Wetland invasion: A multi-faceted challenge during a time of rapid global change. Wetlands 41:64 (Invited review).
Carter, C., J. D Madsen, and G. N. Ervin. 2018. Effects of initial propagule size and water depth on Butomus umbellatus L. growth and vegetative propagation. Aquatic Botany 150: 27-32.
This is a presentation that a former student, Kennedy Calhoun, gave in July 2018, at the national APMS conference in Buffalo, NY.
Resource managers of public lands, such as national wildlife refuges, are tasked with meeting multiple use needs of the fish and wildlife that reside on these lands, as well as the people who utilize those lands for recreational activities such as fishing and boating. Biologists at the Noxubee National Wildlife Refuge (NNWR) have identified the dominance of certain problematic native aquatic plants (American lotus, white water lily, and water shield) as a key obstacle to achieving these multiple use needs in lakes on this and other southeastern wildlife refuges. Few methods are currently known that allow the control of some of the problematic aquatic plant species resource managers encounter while simultaneously enhancing the diversity of desirable plant species, maintaining water quality, and providing diverse aquatic habitats that are needed for many species of wildlife and for human users of these facilities.
This work aims to determine effective methods of managing problematic aquatic plants to enhance aquatic plant diversity in a way that improves the quality of lakes as wildlife habitat and sources of recreational use, while also minimizing potential negative impacts on water quality and desirable plant species. This research will explore chemical control (herbicides) to reduce the abundance of key nuisance plant species, while maintaining diversity of desirable species and also minimizing negative impacts on key water quality parameters (e.g., dissolved oxygen, nitrogen, and phosphorus). We will assess the efficacy of six systemic herbicides and one contact herbicide in a mesocosm trial at MSU’s Aquatic Plant Research Facility. These trials will use two different concentrations of each herbicide and will assess impacts on multiple aspects of plant growth, as well as potential impacts on water quality during the study.