Invasive species are those that are newly settled in an ecosystem. An invasive exotic species is one that has the ability to outcompete other species when introduced into an ecosystem where it does not naturally occur. The Purple loosestrife (Lythrum salicaria) is highly invasive non-native wetlands plant that origin from Europe. It was first introduced to North America in the early 1900s. The purple loosestrife was brought to North America when European sailing ships carried soil (used as ballast; “heavy material, such as gravel, placed low in a vessel to improve its stability”) contained seeds. The plant was also spread by European settlers whom used it as a medicinal plant, and is often sold in nurseries today. The department of natural resources states that the “Purple loosestrife is a tall, branching perennial herb that grows in moist or marshy areas. It can grow to be 8 feet high. In July, it has long spikes of bright purple-pink flowers at the top of the plant. The 1” flowers have 6 pink petals and yellow-white centers. The leaves are long and narrow with pointed tips and smooth edges. They are opposite (two at each joint) and are attached directly to the stem. The stems of purple loosestrife are square and slightly fuzzy. You can feel these edges if you try to roll the stem between your fingers.” When the purple loosestrife is put in an area, especially a disturbed area, the plant absorbs most of the water, nutrients, and oxygen preventing other animals and plants to thrive. Lake Head tells readers that “Lythrum is a very hardy perennial plant that can outgrow cattails, sedges, rushes and the other native aquatic plants on which wildlife depends. The roots of loosestrife form a dense mat that blocks other plants from growing up. Eventually, it chokes out the other vegetation and soon becomes the dominant species. In marshes where a loosestrife seed source is present, the plant can be expected to colonize exposed areas in high...
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