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Purple LooseStrife Flower

The Unknown's picture

They call me a Purple Loosestrife flower. I am the most rampant invasive species in the United States, which I consider a compliment. I am originally from Great Britain, central Russia, northern India, Japan, Manchuria, China, southern Europe, and Southeast Asia. I envelop about 400,000 acres of federal land. Look at how strong and adaptable I am. My proliferation has caused the deterioration of temperate North American wetlands, pastures, marshes, and riparian meadows starting in the beginning of the nineteenth century. I spread through seeds and new roots that germinate from fragmented roots or stems. I have been listed as a deadly species by sixteen states.

I am a perennial plant. I have five to seven pinkish-purple petals and a yellow center. Each of my flower spikes is comprised of several distinctive flowers. When my flowers fall off, I release capsules that are less than one inch long. My capsules are enclosed with numerous small, golden-brown seeds. I am extremely fertile and therefore I can create as many as three million seeds each year. My influence is spread through my seeds which are quickly dispersed by wind, humyns, mud, water, and animals. When I am feeling more confident, I can start germinating the season after my seeds are scattered, but unfortunately my seeds can only stay in the ground, waiting to sprout for many years. 

I damage 190,000 hecatares of wetlands, pastures, riparian meadows, and marshes in North America each year, causing 45 million dollars worth of environmental impact (Regents of the University of Minnesota 3). This money has been used to limit my growth and reviving habitats that I have left in my destructive path. I grow quickly, more than one centimeter a day. I have square, woody stalks that are five or six-sided and can weigh more than 1 kg. I can generate more than 30 shoots each year (Blossey 3). I grow from four to six feet high, depending on the quality of habitat I live in. Once I am mature, I can stretch to two meters horizontally, and I can have as many as 30-50 square, wooded stems from one rootstock, which form wide-topped crowns that take over the herbaceous canopy (Minnesota Department of Agriculture 3). I expand at the base, every year growing more square and fuzzy stems. I require high temperatures and expansive moist soils to germinate. Fortunately, I begin releasing my flowers in the first growing season.

I reached eastern North America in the 1800’s. I was carried on European ships to be used in flower gardens and as a remedy for sores, bleeding, wounds, diarrhea, ulcers, and dysentery (Minnesota Department of Agriculture 3). I soaked in the moist soil that was used for ballast in the ships so they would be stable on the water. I also clung to raw wool and sheep that were brought to North America by colonists. In the 1830s, I became deeply rooted in the New England seafront. My territorial gain synchronized with the increased expansion and need for road networks and the construction of ditches. I spread out in the long open ditches where I moved easily from unprotected to protected wetland habitats.

Mowing near roads has also facilitated the spreading of my seeds and pieces of my stems mechanically. I was also dispersed for agronomical uses and I was fed to bees.  In the 1880s, the inland canals and waterways were built which allowed me to spread into the St. Lawrence River Valley and into New York (Minnesota Department of Agriculture 3). Since I came here, I have continued releasing seeds and advancing. Since 1996, I have now spread to all the Canadian provinces and all the states except Florida.

            My power and influence is known throughout North America because of my perseverance and adaptability. I decrease biodiversity wherever I go. I relish in a prolonged flowering period, lasting from June to September, which gives me a longer time to generate a large amount of seeds. My flowers are one inch long. I stretch out my magenta petals, opening my core, and release the sweetest nectar for pollination. My capsules make my top half reddish-brown. I can reproduce by seed, but also by vegetative propagation, which allows me to encroach on new areas quickly. I reproduce through underground stems at a rate of approximately a foot a year (Swearingen 1). According to the “Minnesota Department of agriculture, I am self-sustatining: “..[My] woody rootstock serves as a storage orphan, providing resources for growth in spring and regrowth if [my] ground shoots are cut or damaged” (Minnesota Department of Agriculture 3). I mostly store starch (Blossey 3). More than one stem may grow from one rootstock of the previous year. My seedlings expand and flourish quickly. Climate challenges do not hinder my expansion and I continue to produce in many environments: low water levels, constant flooding, nutrient shortages and low ph levels. I twist into rock crevices, sprout in sand, and wiggle through organic material and clay.

            I shoot through river and stream banks, skirt on the peripheries of ponds, root myself in stream reservoirs, and dig into ditches. I have green, opposite leaves and my upper half is normally encompassed in short hairs. My leaves are lengthy, about two-six inches long and thin. They are closely affixed to my four-sided erect stem. They are shaped like a lance, and they are rounded at the bottom. Waterfowl and other wetland animals help spread my seeds. I expand into natural and disturbed wetlands.

My destruction of wetlands, by decreasing their opportunities to hold a diversity of wildlife does not inhibit me, I still soak in energy from the sun and germinate on. I create monotypic stands. I change the hydrological and biochemical wetland systems. Wetlands are the most biologically distinct and varied facets of our ecosystem. Hundreds of species of amphibians, fish, reptiles, insects, birds, mammals and other plants depend on nourishing wetlands to survive.

            I smother plant colonies, overtime changing the wetland’s framework and purpose. I cause immense destruction, hiding behind my purple lined petals. I alter the patterns of natural water flow by collecting silt and releasing plant debris, which raises marsh levels. I lower porewater pools of phosphate in the summer. When fish and other wildlife come to eat, find shelter, and spawn in my portentous waters, my purple flowers strangle them. I degrade places where wild rice grows and is gathered. I endanger threatened, fundamental, native wetland plants, such as scrubs, grasses, swamp rose mallows, rushes, cattails, and other flowers, like orchids. I push out more than 44 types of sedges, native grasses, and other flowering plants (National Wildlife Refuge Association 1). These native plants produce a better source of nutrients for birds, insects, and mammals than I do. I wipe out the animal and plant’s shelter and nutrients. Birds, turtles, and frogs nesting sites and habitats are choked and confined by my stems and spikes. In my wake, breeding cycles are disturbed.

            I also obstruct boats from coming and going, as well as blocking hikers, and making it more difficult for bank fisherman to get to the water.

            But do not think that I only attack and encroach on wetlands, I also spread to drier areas, including agricultural land and roadside ditches. This is one of my greatest successes, creating unease as I disturb farmer’s crops and grazing land. I multiply quickly in vacant farmland, almost creating monocultures, occupying large ranges of seasoned meadows and pastures. In Minnesota alone, I have spread to 77 out of the state’s 87 counties covering 58,000 acres of wetlands, lakes, and rivers, where my struggling coinhabitors try to survive my stamina and versatility (Minnesota Department of Agriculture 1).  I congest drainage and irrigation ditches. In irrigation systems, I thwart the water movement, which brings about the deterioration and depletion of foraging in lowland pastures, but my progress must not be hindered.

            I am unique as I decompose in the fall, creating an overflow of sources of nourishment, waiting for native species to decompose in the spring. My timeliness, creates changes in wetland function and endanger species that have been decomposing their plant tissue in the spring. Such great imbalances I am capable of spreading by releasing my precious seeds.

            Rumors have postulated that I had an influence in the local extinction of Black Terns in 1987 since my purple flowers were extending more rapidly during this time, wrapping 19% of the total area, equating to covering 40% of the marsh habitat. The critically endangered bog turtle (Clemmys muhlenbergi Schoepff) surrenders basking and breeding places to me and I have had an impact in the decline of the canvasback duck. The American bittern is affected by my invasions.

            I have spread to critical parts of the coastal lands, swamp, and marsh in Maryland. I seek out wet meadow hay in Maryland, and overrun hay fields, decreasing the value and amount of salt hay that is produced.

            Frankly, I am not feeling vulnerable. My ability to withstand wide ranges of temperature and moisture give me an advantage over my competition. It can take years to destroy me. I have faced the best methods they have used to eradicate me: biological, chemical, and mechanical removal, and I continue to germinate stronger than ever, my bits of stem rooting and resuming the attack. There is no effective method to control me unless I am found in small quantities. I flower over the graves of those who try to eliminate me. 





















Works Cited

"Agency or Department Name Here (for Pda/handhelds)." Purple Loosestrife.        Department of Natural Resources, n.d. Web. 12 May 2015.             <       ex.asp>.

Blossey, B. "Purple Loosestrife - Biological Control of Invasive Plants in the Eastern        United States." Purple Loosestrife - Biological Control of Invasive Plants in the Eastern United States. Invasive Plants of the Eastern U.S.: Identification and          Control., Aug. 2003. Web. 15 May 2015.             <>.

"Invasive Plants of California's Wildland." Cal-IPC:. California Invasive Plant Council,     2015. Web. 12 May 2015. <      mber=182.php>.

Munger, G. T. "Invasive Species: Aquatic Species - Purple Loosestrife (Lythrum Salicaria)." Invasive Species: Aquatic Species - Purple Loosestrife (Lythrum         Salicaria). U.S. Department of Agriculture,   Forest Service, Rocky Mountain        Research Station, Fire Sciences Laboratory., 6 May 2015. Web. 12 May 2015.    <>.

"Prohibited Noxious Weeds: Purple Loosestrife." Minnesota Department of            Agriculture. Minnesota Department of Agriculture, n.d. Web. 12 May 2015.   <     Fnoxiouslist%2F~%2Fmedia%2FFiles%2Fplants%2Fweeds%2Fpurpl            eloosestrifebmp.ashx>.

"Purple Loosestrife | Aquatic Invasive Species | Minnesota Sea Grant." Purple       Loosestrife | Aquatic Invasive Species | Minnesota Sea Grant. Regents of the       Universityof Minnesota, 26 July 2013. Web. 12 May 2015.           <>.

"Purple Loosestrife." National Wildlife Refuge Association. National Wildlife Refuge          Association, n.d. Web. 12 May 2015.                        <         species/purple-loosestrife/>.

"Purple Loosestrife." Purple Loosestrife. Bernd Blossey, 2002. Web. 12 May 2015.          <>.

"Purple Loosestrife: What You Should Know, What You Can Do | Aquatic Invasive          Species | Minnesota Sea Grant." Purple Loosestrife: What You Should Know, What You Can Do | Aquatic Invasive Species | Minnesota Sea Grant. Regents of     the University of Minnesota, 2015. Web. 12 May 2015.             <>.

Rockwell, Fulton. "Invasion Biology Introduced Species Summary Project -           ColumbiaUniversity." Invasion Biology Introduced Species Summary Project -          Columbia University. Columbia University, 9 Nov. 2001.WEB. 15 May 2015.     <            burg/invasion_bio/inv_spp_summ/Lythrum_salicaria.html>.

United States. National Park Service. "PCA Alien Plant Working Group." National          Parks Service. U.S. Department of the Interior, 7 June 2009. Web. 12 May 2015.    <>.