Purple loosestrife, Lythrum salicaria, is a perennial invasive weed that invades lake, river, and wetlands. It was sold as an ornamental until KDA quarantined it in January, 2002. Purple loosestrife is established across the United States and it is also noxious in many states including Nebraska. It is characterized by having a square stem with purple flowers that have 5-6 petals per flower. Since it flowers throughout the summer, it can produce up to 2.7 million seeds per mature plant. These characteristics allow purple loosestrife to invade and squeeze out native vegetation rapidly.
Biological control offers the ability to provide long term control for exotic weed species. The goal of biological control is to reduce the pest population, not to eradicate it. In Kansas, a leaf feeding beetle, Galerucella calmariensis, is available for biological control for purple loosestrife. KDA has released Galerucella calmariensis in Doniphan County around Troy's city lake and in Lynn County near Mound City. The release of this leaf feeding beetle is considered to be safe since it doesn't feed on native lythrum species and prefers purple loosestrife.
In addition to a biological control effort, KDA along with Kansas Department of Wildlife and Parks have been involved with an eradication effort around Waconda and Lovewell lakes in north central Kansas.