When we talk about invasive plants, the first thing that comes to mind are plants in gardens, pastures or woodlands. Often overlooked are invasive and non-native plants in water gardens and shoreline plantings. Invasive plants and invasive animals are becoming a serious threat in wetlands, lakes, rivers, and streams in all of Minnesota.Gardeners have a great interest today in water gardening that ranges from small plastic water features, elaborate constructed ponds, rain gardens, and even retention ponds. The choice and sources for aquatic plants is often limited and largely unfamiliar. The danger of non-native plants escaping into our lakes and streams has increased significantly. Not only are non-native plants a problem, but fish, amphibians and invertebrates threaten native waters as well. Two examples are the zebra mussel and goldfish that have become established in some Minnesota waters.How do these species unintentionally get planted? One way is that they hitchhike with orders of plants from various suppliers. University of Minnesota research found that 93% of aquatic plant orders from many different suppliers contained plant fragments, seeds, or rhizomes of other species. So often you get more than you pay for! It is important to buy from reliable sources and to carefully examine your plant for any fragments or seeds.Sometimes invasives are introduced with the best of intentions. The yellow iris and flowering rush are two examples of non-native plants that have quickly taken over large areas of shoreland due to a lack of natural predators. There are numerous lakes south of here being taken over by floating yellow heart, another pond escapee. Many people place water hyacinth and water lettuce in their ponds. They are both prohibited plants in southern states and have not survived the winters here yet. It is important to identify and know about anything you plant that can find its way to any body of water.Goldfish or koi are so cute when they were little and pose a problem when they grow beyond the size of the pond. In a simililar light, bullfrogs brought up from the south are not native here. Often these creatures get put into a lake or river because the owner just does not have the heart to dispose of them properly. It's really no different than planting that loosestrife down by the dock because the color is a good match for the boathouse.By being aware of what you stock your water garden or pond with and taking care in sharing or transporting plants and animals in water features, you can minimize the impact of these invasives. Sea Grant Minnesota is a cooperative project between the U of M, DNR, the Minnesota Water Garden Society, and 38 members of the Minnesota Nursery and Landscape Association. They list the following steps you can take to minimize introduction of aquatic invasives:Thanks to all who participated at the Beltrami County Fair in the Horticulture Department. 
