Principal source: VDCR/VNPS (Virginia Department of Conservation and Recreation and Virginia Native Plant Society). UNDATED. Invasive Alien Plant Species of Virginia: Crown Vetch (Coronilla varia L.)
Tu, M. 2003. Element Stewardship Abstract for Coronilla varia L.. The Nature Conservancy.
Compiler: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
Review: Dr. Nathan L. Hartwig Prof. Of Weed Science Emeritus \ The Pennsylvania State University
Publication date: 2005-07-08
Recommended citation: Global Invasive Species Database (2025) Species profile: Coronilla varia. Downloaded from http://iucngisd.org/gisd/species.php?sc=276 on 28-01-2025.
\r\nPhysical: Manual or mechanical methods of plant removal can control C. varia in small, isolated patches. These methods, however, are very time and labor-intensive because all pieces of the roots, must carefully be removed to avoid resprouting. Populations must be monitored for several years following plant removal because seeds stored in the soil seed bank may germinate for up to 10 years. Cutting or mowing at a frequency of less than once per year is not effective at controlling populations, but does offer a method for temporarily stopping or slowing its spread. Mowing around the periphery of the desired vegetation (natural area) will keep it from spreading into the area vegetatively, but does not prevent the arrival of seeds. Cutting or mowing removes standing biomass only, so spray herbicides have higher efficacy. Grazing can be used in combination with an herbicide treatment for control.
\r\nChemical: Herbicides are currently the most effective means to control large infestations. Herbicides can be applied with either backpack sprayers (to minimise overspray) or with a boom. Dicamba, 2,4-D, glyphosate, triclopyr, or clopyralid may be used, and 2,4-D (amine or ester) or Glyphosate applied as a 1% or 2% solution can be foliar-applied for good control when C. varia is actively growing. A 2% solution of triclopyr kills 99% of C. varia in large infestations. Clopyralid is a more target-specific herbicide than glyphosate, 2,4-D, or triclopyr, and a 0.25% solution of clopyralid with 0.5% surfactant can kill up to 100% of C. varia cover. All of these herbicides are active on most other native and non-native broadleaved species (dicots) and glyphosate is active on all species (monocots and dicots). Multiple applications will be required over a period of several years since dormant crownvetch seed can regenerate the stand for up to ten years after elimination of the live plants. Crownvetch is tolerant to imazethapyr, imazapic and many other herbicides.