Lythrum salicaria - L.
Purple Loosestrife
Other Common Names: purple loosestrife
Taxonomic Status: Accepted
Related ITIS Name(s): Lythrum salicaria L. (TSN 27079)
Unique Identifier: ELEMENT_GLOBAL.2.160902
Element Code: PDLYT090B0
Informal Taxonomy: Plants, Vascular - Flowering Plants - Loosestrife Family
 
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Dicotyledoneae Myrtales Lythraceae Lythrum
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Concept Reference
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Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Lythrum salicaria
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 22Mar1994
Global Status Last Changed: 22Mar1994
Rounded Global Status: G5 - Secure
Nation: United States
National Status: NNA
Nation: Canada
National Status: NNA (31Jul2016)

U.S. & Canada State/Province Status
United States Alabama (SNA), Arkansas (SNA), California (SNA), Colorado (SNA), Connecticut (SNA), Delaware (SNA), District of Columbia (SNA), Idaho (SNA), Illinois (SNA), Indiana (SNA), Iowa (SNA), Kansas (SNA), Kentucky (SNA), Maine (SNA), Maryland (SNA), Massachusetts (SNR), Michigan (SNA), Minnesota (SNA), Mississippi (SNA), Missouri (SNA), Montana (SNA), Nebraska (SNA), Nevada (SNA), New Hampshire (SNA), New Jersey (SNA), New York (SNA), North Carolina (SNA), North Dakota (SNA), Ohio (SNA), Oregon (SNA), Pennsylvania (SNA), Rhode Island (SNA), South Dakota (SNA), Tennessee (SNA), Texas (SNA), Utah (SNA), Vermont (SNA), Virginia (SNA), Washington (SNA), West Virginia (SNA), Wisconsin (SNA), Wyoming (SNA)
Canada Alberta (SNA), British Columbia (SNA), Manitoba (SNA), New Brunswick (SNA), Newfoundland Island (SNA), Nova Scotia (SNA), Ontario (SNA), Prince Edward Island (SNA), Quebec (SNA), Saskatchewan (SNA)

Other Statuses

NatureServe Global Conservation Status Factors

Other NatureServe Conservation Status Information

Distribution
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U.S. States and Canadian Provinces
Color legend for Distribution Map
NOTE: The distribution shown may be incomplete, particularly for some rapidly spreading exotic species.

U.S. & Canada State/Province Distribution
United States ALexotic, ARexotic, CAexotic, COexotic, CTexotic, DCexotic, DEexotic, IAexotic, IDexotic, ILexotic, INexotic, KSexotic, KYexotic, MA, MDexotic, MEexotic, MIexotic, MNexotic, MOexotic, MSexotic, MTexotic, NCexotic, NDexotic, NEexotic, NHexotic, NJexotic, NVexotic, NYexotic, OHexotic, ORexotic, PAexotic, RIexotic, SDexotic, TNexotic, TXexotic, UTexotic, VAexotic, VTexotic, WAexotic, WIexotic, WVexotic, WYexotic
Canada ABexotic, BCexotic, MBexotic, NBexotic, NFexotic, NSexotic, ONexotic, PEexotic, QCexotic, SKexotic

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
MO Adair (29001), Andrew (29003), Atchison (29005), Boone (29019), Callaway (29027), Carroll (29033), Cass (29037), Cedar (29039), Clay (29047), Clinton (29049), Cole (29051), DeKalb (29063), Franklin (29071), Greene (29077), Henry (29083)*, Holt (29087), Howell (29091), Jackson (29095), Lafayette (29107), Lewis (29111), Macon (29121), Maries (29125), Marion (29127), Mississippi (29133), Montgomery (29139), New Madrid (29143), Pemiscot (29155), Pettis (29159), Pike (29163), Pulaski (29169), Putnam (29171)*, Randolph (29175), Ray (29177), Saline (29195), Schuyler (29197), Scotland (29199), Scott (29201), St. Charles (29183), St. Louis (29189), Sullivan (29211)*, Warren (29219)
NV Washoe (32031)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
07 Bear-Wyaconda (07110001)+, North Fabius (07110002)+, The Sny (07110004)+, North Fork Salt (07110005)+, South Fork Salt (07110006)+, Salt (07110007)+, Cuivre (07110008)+, Peruque-Piasa (07110009)+, Cahokia-Joachim (07140101)+, Meramec (07140102)+, Bourbeuse (07140103)+*
08 Lower Mississippi-Memphis (08010100)+, New Madrid-St. Johns (08020201)+
10 Keg-Weeping Water (10240001)+, Tarkio-Wolf (10240005)+, Platte (10240012)+, One Hundred and Two (10240013)+*, Upper Chariton (10280201)+, Lower Chariton (10280202)+, Little Chariton (10280203)+, Sac (10290106)+, South Grand (10290108)+, Lower Osage (10290111)+, Lower Missouri-Crooked (10300101)+, Lower Missouri-Moreau (10300102)+, Lamine (10300103)+, Blackwater (10300104)+, Lower Missouri (10300200)+
11 James (11010002)+, North Fork White (11010006)+
16 Truckee (16050102)+
18 Honey-Eagle Lakes (18080003)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Technical Description: Lythrum salicaria is a stout, erect perennial herb with a strongly developed taproot. The plant ranges in height from 0.5 to 2.0 m. The four-angled stem can be glabrous to pubescent. The sessile leaves are opposite or in whorls, lanceolate to narrowly oblong, with cordate bases. The inflorescence is spike-like, 1-4 dm long. Petals 5-7, usually magenta, but white or light pink flowers are also common. The flowers are trimorphic in regard to the relative lengths of the stamens and style. The fruit is a capsule, with small seeds, each weighing 0.06 mg (Balogh 1985, Rawinski 1982, Gleason 1952, Fernald 1950).
Diagnostic Characteristics: At a distance, L. salicaria may be confused with Epilobium angustifolium, Verbena hastata, Teucrium canadense, or Liatris spp. Upon closer examination however, purple loosestrife is easily distinguished from these other magenta-flowered plants.
Ecology Comments: Purple loosestrife begins to bloom in July and continues until September or October. The flowers are pollinated by several different types of bees from the Megachilinae, Apinae, Xylopinae, and Bombinae; and by several butterflies: Pieris rapae, Colias philodice, and Cercyonis pegala (Balogh 1985). Seed production is prolific. There is an average of 120 seeds per capsule and up to 900 capsules per plant (Rawinski 1982). The lowest capsules on the stem are dehiscing while the upper stem capsules are still green.

The seeds are small, weighing 0.06 mg each (Shamsi and Whitehead 1974). Dispersal is mainly by wind, but seeds can also be transported on the feet of waterfowl or other wetland animals. Red-winged blackbirds have been observed eating the seeds (Rawinski 1982). Humans carry seeds inadvertently on clothing and shoes and in some instances, bee-keepers have purposely sown seeds in headwaters and wetlands to provide a steady source of nectar for their bees. The seeds and cotyledon stage seedlings are buoyant and can be dispersed by water currents (Balogh 1985). The seed bank potential for L. salicaria is enhanced by the high viability of the seeds. Viability decreased from 99% to 80% after two years of storage in a natural body of water (Rawinski 1982).

Seeds of L. salicaria can germinate in acidic or alkaline soils; in soils that are nutrient rich or nutrient poor. Light requirements for germination are minimal (Shamsi and Whitehead 1974). Temperature at the soil surface is a critical factor for germination. Seeds will germinate at temperatures ranging from 15 to 20 degrees C (Balogh 1985). Seeds germinate in high densities--about 10,000 to 20,000/sq. meter (Rawinski 1982). The interval between germination and flowering is eight to ten weeks (Rawinski 1982).

Seedlings that germinate in the spring grow rapidly and will produce a floral shoot up to 30 cm in length the first year. Summer-germinated seedlings develop only five or six pairs of leaves before the end of the growing season (Shamsi and Whitehead 1974). Spring-germinated seedlings have a higher survival rate than summer-germinated seedlings. Open grown shoots have a greater reproductive output than shoots growing in dense stands (Rawinski 1982). Once established, seedlings can survive shallow flooding of up to 30-45 cm in depth (Thompson and Stuckey 1980.).

The taproot is strongly developed in the seedling stage and persists throughout the life of the plant (Shamsi and Whitehead 1974). In mature plants, the taproot and major root branches become thick and woody (Rawinski 1982). The semi-woody aerial shoots die in the fall but persist for one to two years making stands of L. salicaria very dense. New shoots arise the following spring from buds at the top of the rootstocks (Rawinski 1982).

The rootstock is the main organ of perennation and vegetative spread is therefore limited (Shamsi and Whitehead 1974). L. salicaria can spread vegetatively by resprouting from cut stems and regenerating from pieces of root stock (Rawinski 1982).

Infestations of purple loosestrife appear to follow a pattern of establishment, maintenance at low numbers, and then dramatic population increases when conditions are optimal. L. salicaria flourishes in wetland habitats that have been disturbed or degraded from draining, natural drawdown in dry years, bulldozing, siltation, shore manipulation, cattle trampling, or dredging. Mudflats exposed following drawdowns will be quickly colonized if a loosestrife seed source is present. Seeds are usually present in such large numbers and germinate in such high densities that growth of native seedlings is suppressed (Rawinski 1982). Loosestrife crowds or shades out native species and eventually becomes a virtually monospecific stand.

L. salicaria is an extremely successful invader of wetlands that have been subjected to some type of disturbance: drawdown, siltation, drainage, ditching. Expansion in a wetland can be extensive and sudden due to the abundance of seeds produced and the rapid growth of seedlings. High seed viability and prolific seed production can build up a seed bank of massive proportions.

Purple loosestrife seed germinates in such high densities that it outcompetes native seedlings. The buildup of debris around the roots enable loosestrife to invade deeper water and to form dense stands that shade out other emergents and push out floating vegetation by closing open water spaces.

Habitat Comments: L. salicaria is native to Eurasia and was first reported from the northeastern coast of North America in 1814, (Stuckey 1980). Although purple loosestrife occurs in nearly all sections of the United States, the heaviest concentrations are in the glaciated wetlands of the northeast. Occurrences west of the Mississippi River appear to be scattered (Stuckey 1980), with the species establishing in reclamation projects in the west (Thompson and Jackson 1982).

Purple loosestrife is found in wetlands such as cattail marshes, sedge meadows, and open bogs. L. salicaria also occurs along stream and river banks and lake shores. In addition, the plant is found in ditches and other disturbed wet soil areas.

L. salicaria grows best in high organic soils, but tolerates a wide range of soils including clay, sand, muck, and silt (Thompson and Jackson 1982). Generally, the plant is found in full sun, but it can survive in 50% shade (Thompson and Jackson 1982). Typical associates include Typha latifolia, T. glauca, Phragmites australis, Spartina sp., Scirpus spp., and Carex spp. (Thompson and Jackson 1982).

Economic Attributes Not yet assessed
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Management Summary
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Stewardship Overview: Monitor natural areas for the presence of L. salicaria. Maintain preserves so that purple loosestrife cannot invade and flourish. For small infestations, eradication is possible with spot applications of glyphosate herbicides. Monitor the containment and control procedures.

Current methods for eradicating large, dense populations of loosestrife are not totally effective. Mechanical contol methods are ineffective, and the herbicide most effective is non-selective. Realistically, the long-term control of large populations may require biological controls and/or better herbicides, but their development is at least several years away. Therefore, containment and minimizing seed production are the present contol objectives for large dense populations. (MN DNR 1987)

Management Requirements: Once purple loosestrife becomes established in a wetland it displaces endemic vegetation through rapid growth and heavy seed production (Rawinski 1982). L. salicaria has a detrimental impact on native wetland vegetation and associated wildlife. Important wildlife food plants such as cattails and pondweed are displaced or shaded out as L. salicaria expands across a wetland. If purple loosestrife is left unchecked, the wetland eventually becomes a monoculture of loosestrife (Rawinski 1982). The invasion of L. salicaria leads to a loss of plant diversity, which also leads to a loss of wildlife diversity.

Management objectives may include eradicating populations, containing populations or preventing establishment. Monitoring should be used to track the accomplishment of these objectives.

The best time to search for purple loosestrife is in July and August when the plants are blooming. The bright magenta flowers are easy to spot at a great distance. Aerial surveys can be used to note the yearly position of large populations. An advancing or receding boundary would be identifiable from air photos. Ground surveys are more feasible for tracking small populations and finding newly established populations. Look for seedlings in June.

The following individuals are involved in public awareness campaigns or wetland surveys:

John Schwegman, Director, Botany Program, Illinois Dept. Conservation, Springfield, Illinois 62706.

Rich Henderson, Consultant, Natural Areas Management, 2845 Timberlane Verona, Wisconsin 53593.

Noel Cutright, Purple Loosestrife Task Force, 3352 Knollwood Rd., West Bend, Wisconsin 53095.

Purple loosestrife Survey-Nevin, Wisconsin Dept. Natural Resources, P.O. Box 7921, Madison, Wisconsin 53791.

Jay Rendall, Coordinator, Purple Loosestrife Program, Minnesota Dept. Natural Resources, Box 25, 500 Lafayette Rd., St. Paul, MN 55155.

Several control methods have been attempted with varying degrees of success. Natural area managers must determine their objectives first. Is it more feasible to contain or control populations of purple loosestrife? Large populations extending over three acres or more will be difficult if not impossible to completely eradicate using presently known methods. These large populations should be contained at their present position. Preventing the expansion can be accomplished through hand-pulling new plants along the periphery or spraying herbicide on plants extending beyond the main body of the population. Smaller populations can be controlled through eradication. Populations up to three acres can be cleared with herbicides or hand-pulled, depending upon the size of the work crew and time available.

CHEMICAL: The herbicide glyphosate is most commonly used to control L. salicaria. Glyphosate is available under the trade names RoundupTM and RodeoTM, manufactured by Monsanto. Roundup cannot be used over water. Another formulation of glyphosate known as Rodeo contains a non-ionic surfactant and has been approved for use over water. Ortho X-77 is the non-ionic surfactant recommended for use with Rodeo, but several other non-ionic surfactants were cleared for use with Rodeo in 1985 (Balogh 1985).

The major disadvantage in using Rodeo is that glyphosate is a non-specific systemic. Broadcast spraying of non-selective herbicides kills all of the vegetation and may result in an increase in loosestrife density because of seed germination following the removal of competing perennial vegetation (Minnesota DNR 1987). Spot application of Rodeo directly onto L. salicaria would ensure that no large holes would appear in the marsh vegetation and that competition would be unaffected. The safest method of applying glyphosate herbicide is to cut off all stems at about 6 inches and then paint or drip onto the cut surface a 20-30% solution (Henderson 1987).

Spraying should be done after the period of peak bloom, usually late August (Balogh 1985, Rawinski 1982). One to two percent solutions of Rodeo have been recommended as sufficient to kill L. salicaria (Henderson 1987, Minnesota DNR 1987, Balogh 1985, Thrune pers. comm.). Work done by Jim Reinartz at the U.W.-Milwaukee Field Station indicates it is best to spray no more than 25-50% of a plant's foliage (Henderson 1987). This will help protect against overspraying which might damage adjacent vegetation.

It is critical that any control effort be followed up the same growing season and for several years afterwards since some plants will be missed, new seedlings may sprout from the extensive seed bank, and a few plants will survive the low-dosage treatment (Henderson 1987, Minnesota DNR 1987). Higher dosage and careless application, however, inevitably kills more surrounding vegetation and leads to establishment of loosestrife seedlings (Minnesota DNR 1987).

For larger infestations where spot application of glyphosate is not practical, broadleaf herbicides can be used. They have the advantage of not harming monocot species, which are the dominants in most wetland types. Broadleaf herbicides (2,4-D based) can be effective on loosestrife if applied in late May or early June (Henderson 1987). The disadvantage of treating early in the season is that purple loosestrife plants are easily overlooked when not in flower. A combination of 2,4-D and dicamba has been used on a limited basis in western irrigation ditches (Jackson pers. comm.). The EPA has approved a 1:1 tank mix of these two products. Once L. salicaria has reached 10-15% of its mature growth, it can be sprayed with good results. To ensure complete coverage and compensate for spotty application, repeat the treatment once during the growing season (Jackson pers. comm.).

PULLING: Hand-removal is recommended for small populations and isolated stems. Ideally, the plants should be pulled out before they have set seed. The entire rootstock must be pulled out since regeneration from root fragments is possible. Be sure to minimize disturbances to the soil and native vegetative cover. Remove uprooted plants and broken stems from the area since the broken stems can resprout (Rawinski 1982).

REPLACEMENT: Replacement control has been attempted in several wildlife refuges (Balogh 1985, Rawinski 1982). Rawinski (1982) sowed Japanese millet (Echinochloa frumentacea) with L. salicaria and found that the millet seedlings outcompeted the loosestrife seedlings. The millet must be planted immediately after marsh drawdown has occurred. Balogh (1985) found that Japanese millet does not regenerate well and would have to be replanted every year. Balogh (1985) attempted a replacement treatment using native seed. Polygonum lapathifolium was seeded with purple loosestrife and the Polygonum outcompeted the loosestrife. However, the following spring L. salicaria would start growing first due to its overwintering rootstock. Replacement methods would have a very limited application within a natural area, but they may be useful to control or contain loosestrife populations on buffer property.

BIOLOGICAL: Several characteristics of L. salicaria make it an ideal candidate for biological control (USFWS 1987). Batra (et al. 1986) recommends detailed ecological and host-specificity studies for six European species: a cecidomyiid fly whose galling can reduce purple loosestrife foliage by 75% and seed production by 80%; a stem and root boring weevil; two chrysomelids that can cause nearly 50% defoliation; and two weevils that mine ovaries and seeds. The results of Batra et al. (1986) indicated that the chances of successful biological control of L. salicaria in North America are excellent.

The following individuals are familiar with L. salicaria and can suggest control strategies:

Dottie Thompson, Horicon National Wildlife Refuge, Rt. 2, Mayville, Wisconsin 53050. (414) 387-2658.

Rich Henderson, Consultant, Natural Area Management, 2845 Timberlane, Verona, Wisconsin 53593. (608) 845-7065.

John Schwegman, Director, Botany Program, Illinois Dept. Conservation, Springfield, Illinois 62706.

Tom Jackson, Leader, Field Research Station, U.S. Fish and Wildlife Service, P.O. Box 25007, Denver, Colorado 80225.

Jay Rendall, Coordinator, Purple Loosestrife Program, MN Dept of Natural Resources, Box 25, 500 Lafayette Rd, St. Paul, MN 55155.

Management Research Programs: A research project in Wisconsin includes investigations on different methods of control and different herbicide treatments. The ecology of L. salicaria including seed bank buildup is also under investigation. Contact: Rich Henderson, Consultant-Natural Area Management. 2845 Timberlane, Verona, Wisconsin 53593.

Hand cutting purple loosestrife and fertilizing cattails under varying degrees of wetness is being studied at Indiana Dunes National Lakeshore. Contact: Ron Heibert, Chief, Division of Science, 1100 N. Mineral Springs Rd., Porter, Indiana 46304.

Research on the effectiveness of various chemical controls will be conducted in Illinois, pending funding. Contact: John Schwegman, Director, Botany Program, Illinois Dept. Conservation, Springfield, Illinois 62706.

A research project funded by the Metropolitan Council (MN) is being conducted by Hennepin County Park Reserve. Chemical control techniques are to be evaluated for 2 years in control plots. Contact: Tom Hollenhorst, Hennepin County Park Reserve, 3800 Co. Rd. 24, Maple Plain, MN 55359.

The Minnesota Legislative Commission on Minnesota Resources (LMCR) has funded a comprehensive control program over a two year period. The program will inventory purple loosestrife in Minnesota, keep abreast of current contol methods and research, implement a prioritized control program, monitor environmental impact and effectiveness of control, promote public awareness campaigns, and coordinate agencies control efforts within the state. Contact: Jay Rendall, Coordinator, Purple Loosestrife Program, MN Dept of Natural Resources, Box 25, 500 Lafayette Rd, St. Paul, MN 55155.

Management Research Needs:

Biological control methods should be a priority for research. Repeated chemical treatments are costly and the long-term effects on natural systems are not fully understood. Preliminary investigations in Europe have revealed several host-specific insects that keep L. salicaria in check. Further research is warranted. Research is needed to assess the potential productivity of the seed bank. How extensive is the seed bank in a wetland in comparison to the size of the above-ground population? What is the rate of seed buildup? Can the age of a seed bank be determined? What is the viability of purple loosestrife seed? More research is needed on herbicide treatments that will give the most selective application with the least impact to the surrounding competitive vegetation, i.e. wick applications, etc. Available information suggests that research on mechanical treatments will not yield helpful results.

Population/Occurrence Delineation Not yet assessed
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Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank)
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Disclaimer: While I-Rank information is available over NatureServe Explorer, NatureServe is not actively developing or maintaining these data. Species with I-RANKs do not represent a random sample of species exotic in the United States; available assessments may be biased toward those species with higher-than-average impact.

I-Rank: High
Rounded I-Rank: High
I-Rank Reasons Summary: This extremely invasive species has the potential to completely dominate a wetland setting, forming a vast, monotypic stand. It can crowd out, outcompete, and completely eliminate native species and aquatic plant layers and suppresses and eliminates native plants and seed growth. It can potentially hybridize with native loosestrife, which is considered rare in some states. The species is very widespread in the U.S. occurring almost everywhere and is considered invasive in most states. Seeds are easily and widely dispersed by water and the plant is extremely prolific, even in undisturbed areas. Eradication is possible for early infestations but is often costly and time consuming with millions of dollars being spent annually on removal of this species in the U.S.
Subrank I - Ecological Impact: High
Subrank II - Current Distribution/Abundance: High
Subrank III - Trend in Distribution/Abundance: High
Subrank IV - Management Difficulty: High
I-Rank Review Date: 26Jun2006
Evaluator: J. Cordeiro
Native anywhere in the U.S?
Native Range: Lythrum salicaria is native to Eurasia (Bender, 1987) extending from Great Britain to central Russia, Japan, Manchurian China, southeastern Asia, and northern India (ISSG, 2005).

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Screening Questions

S-1. Established outside cultivation as a non-native? YES
Comments: This species was introduced to the United States in the early 1800s (Bender, 1987) and has invaded many areas of the world including Canada, the United States, Ethiopia, and Australia (ISSG, 2005). This species has been listed among the most frequently listed in a recently compiled database of noxious weeds in the United States and Canada (Skinner et al., 2000).

S-2. Present in conservation areas or other native species habitat? Yes
Comments: This species is widespread across the United States and 24 states have laws to discourage its spread (Czarapata, 2005).

Subrank I - Ecological Impact: High

1. Impact on Ecosystem Processes and System-wide Parameters:High/Moderate significance
Comments: In its native habitat, purple loosestrife only comprises one to four percent of the native vegetation, but in North America, densities of up to 80,000 stalks per acre have been recorded (Strefeler et al., 1996). It can completely dominate a wetland setting, forming a vast monotypic stand.

2. Impact on Ecological Community Structure:High significance
Comments: Purple loosestrife crowds out native species by creating an overstory and eventually may become monospecific. In its native habitat, purple loosestrife only comprises one to four percent of the native vegetation, but in North America, densities of up to 80,000 stalks per acre have been recorded (Strefeler et al., 1996). Uncontrolled, purple loosestrife eventually forms a near monoculture that alters the structure of natural plant communities and reduces biological diversity. Dense stands can change drainage patterns by restricting the flow of water (Snyder and Kaufman, 2004). Recent studies (Morrison, 2002), however, have shown that purple loosestrife stands were not monospecific in wetlands and other non-native species may come to dominate if purple loosestrife is removed, and that small gaps may provide regeneration niches for other species amidst dense assemblages of purple loosestrife.

3. Impact on Ecological Community Composition:High significance
Comments: Once established, purple loosestrife displaces native vegetation through rapid growth and heavy seed production (Bender, 1987).

4. Impact on Individual Native Plant or Animal Species:High significance
Comments: Conflicting reports exist as to whether Lythrum salicaria impacts density, richness, or diversity of other plant species. It has been reported that seeds often germinate in such high numbers that native seedling growth is suppressed and native species may be outcompeted (ISSG, 2005). Wildlife food plants such as cattails and pondweed are displaced or shaded out as Lythrum salicaria expands across a wetland (Rawinski, 1982 cited in Bender, 1987). Studies have documented the competetive displacement of cattail (Mal et al., 1997; Weihle and Neely, 1997) and declines in habitat quality for muskrats and waterfowl (ISSG, 2005). Gabor et al. (1996) found native species replaced adult purple loosestrife after its removal but purple loosestrife eventually reestablished dominance. On the other hand, Farnsworth and Ellis (2001) found little correlation between L. salicaria density or cover and other plant species, and loose correlation with actual increase in numbers of some other species (they did find lower biomass of other plants, however, in presence of L. salicaria). Morrison (2002) similarly found overall richness measurements in New York, Ontario, and Connecticut wetlands do not support the perception that purple loosestrife establishes monospecific stands and displaces native species. This indicates that although diversity and density of other wet meadow plant species is not negatively affected, L. salicaria may come to predomonate n these systems by attaining a larger size (competition for biomass). As for impact on animals, Gardner et al. (2001), however, determined that monotypic stands of purple loosestrife are not lacking in aquatic invertebrates, although individual sizes of some taxa tend to be smaller. In recent years, its has spread rapidly in the midwest in recent years, threatening native plants (including rare species0, but also the widllife that depend on them for food and shelter (Czarapata, 2005).

5. Conservation Significance of the Communities and Native Species Threatened:High significance
Comments: Lythrum salicaria can potentially hybridize with native loosestrife, Lythrum alatum, which is considered rare in some states, potentially reducing the gene pool for the rarer species. In recent years, its has spread rapidly in the midwest in recent years, threatening native plants (including rare species), but also the wildlife that depend on them for food and shelter (Czarapata, 2005). In 1995, the National Park Service determined that purple loosestrife was a potential threat to state listed endangered plant species, special concern plant species, and two globally rare calcareous riverside plant communities documented from the Delaware Water Gap National Recreation Area (Shank and Shreiner, 1999). Several limestone fens, a globally rare plant community, are threatened by the invasion of purple loosestrife in New Jersey (Snyder and Kaufman, 2004). Also in New Jersey, several populations of the federally listed bog turtle (Clemmys muhlenbergii) are threatened by loss of habitat through the invasion of purple loosestrife and a population of the state listed endangered wiry panic grass (Panicum flexile) was lost when its open fen habitat was succeeded by a dense stand of purple loosestrife (Snyder and Kaufman, 2004).

Subrank II. Current Distribution and Abundance: High

6. Current Range Size in Nation:High significance
Comments: This species occurs in nearly all sections of the United States, with the heaviest concentrations in the glaciated wetlands of the northeast; occurrences west of the Mississippi River are scattered (Bender, 1987; Mills et al., 1997; ISSG, 2005), notable exceptions include Florida, New Mexico, Arizona, Lousiana, Georgia, Alaska, and Hawaii (Benson et al., 2001; 2004).

7. Proportion of Current Range Where the Species is Negatively Impacting Biodiversity:High significance
Comments: Although it is considered invasive throughout the United States, purple loosestrife has become extremely aggressive in the northeast (Crow and Hellquist, 2000). In recent years, its has spread rapidly in the midwest in recent years, threatening native plants (including rare species0, but also the widllife that depend on them for food and shelter (Czarapata, 2005). This species has been listed among the most frequently listed in a recently compiled database of noxious weeds in the United States and Canada (Skinner et al., 2000). Not less than 24 states have laws to discourage the spread of purple loosestrife (Czarapata, 2005).

8. Proportion of Nation's Biogeographic Units Invaded:High significance
Comments: It is conservatively estimated that far greater than half of the 81 ecoregions have been invaded by Lythrum salicaria in the United States (Cordeiro, pers. obs., June 2006, based on TNC, 2001).

9. Diversity of Habitats or Ecological Systems Invaded in Nation:Moderate significance
Comments: Purple loosestrife is found in a variety of wetlands such as cattail marshes, sedge meadows, floodplains, and open bogs, but also occurs along stream and river margins and lake shorelines (Crow and Hellquist, 2000). It is also found in ditches and disturbed wet soil areas (Bender, 1987; ISSG, 2005). It grows best in high organic soils but tolerates a wide range including clay, sand, muck and silt.

Subrank III. Trend in Distribution and Abundance: High

10. Current Trend in Total Range within Nation:High significance
Comments: Purple loosestrife is increasing rapidly across North America although it is already found in nearly every state. Although it is considered invasive throughout the United States, purple loosestrife has become extremely aggressive in the northeast (Crow and Hellquist, 2000). In recent years, its has spread rapidly in the midwest in recent years, threatening native plants (including rare species), but also the widllife that depend on them for food and shelter (Czarapata, 2005). This species has been listed among the most frequently listed in a recently compiled database of noxious weeds in the United States and Canada (Skinner et al., 2000). Not less than 24 states have laws to discourage the spread of purple loosestrife (Czarapata, 2005).

11. Proportion of Potential Range Currently Occupied:Low significance
Comments: Since this species is present in nearly every U.S. state, most of its potential range is nearly occupied.

12. Long-distance Dispersal Potential within Nation:High significance
Comments: Seeds are borne in capsules that burst at maturity in late July or August and can be carried downstream in rivers and survive submerged for 20 months in water (Czarapata, 2005). Dispersal is mainly by wind but seeds can also be transported on feet or feathers of waterfowl or other wetland animals. Humans also carry seeds inadvertently on clothing and shoes. At the cotyledon stage are buoyant can can be dispersed by water (Bender, 1987). Mills et al. (1997) cited original infestations in the Hudson River basin (as far back as 1867) from dry ballast waste from ships and in waste from woolen mills. Although considered a noxious weed by the U.S. federal government and in many states, it continues to be sold in the nursery and landscape trade (Uva et al., 1997).

13. Local Range Expansion or Change in Abundance:High significance
Comments: In the United States, mean rate of spread since 1940 is estimated to be 645 square km per year (Thompson, 1991). In recent years, its has spread rapidly in the midwest in recent years, threatening native plants (including rare species0, but also the widllife that depend on them for food and shelter (Czarapata, 2005). Not less than 24 states have laws to discourage the spread of purple loosestrife (Czarapata, 2005).

14. Inherent Ability to Invade Conservation Areas and Other Native Species Habitats:High significance
Comments: This species is listed as an "invasive plant of major concern" in Czarapata (2005). Seed production is prolific with an average of 120 seeds per capsule and up to 900 capsules per plant (Rawinski, 1982 cited in Bender, 1987). Single stems can produce 100,000 to 300,000 seeds annually and large, mature plants can have 50 or more stems (Czarapata, 2005). Most seeds fall near the parent plant but water, animals, boats, and humans assist in transporting them long distances. Natural dispersal is mainly by wind but seeds can also be transported on feet or feathers of waterfowl or other wetland animals. Humans also carry seeds inadvertently on clothing and shoes. At the cotyledon stage are buoyant can can be dispersed by water. The seed bank potential is enhanced by high seed viability, even in acidic or alkaline soils or soils that are nutrient poor (Bender, 1987). Seedlings that germinate in spring grow rapidly, but the species also germinates in summer (Shamsi and Whitehead, 1974). Although not as viable as spring germinating seedlings, seedlings that emerge during late summer through early September in Minnesota were found to survive the winter to create additional populations in wetland mudflats the following year (Katovich et al., 2003). Plants can propogate vegetatively by resprouting from cut stems and regenerating from root stock pieces (Bender, 1987; ISSG, 2005). In one growing season, an individual plant may produce over a million seeds, which can remain viable for several years (Welling and Becker, 1990), even under water for about 20 months (ISSG, 2005). Survival rate of seeds is 60-70% (Czarapata, 2005). In its native habitat, purple loosestrife only comprises one to four percent of the native vegetation, but in North America, densities of up to 80,000 stalks per acre have been recorded (Strefeler et al., 1996). Seedlings of purple loosestrife are also highly tolerant of submergence accumulating very high biomass at up to 6 cm depth submergence (Fraser and Karnezis, 2005).

15. Similar Habitats Invaded Elsewhere:Low significance
Comments: Habitats invaded elsewhere are believed to be similar to in the U.S. This species is considered an invasive in many countries.

16. Reproductive Characteristics:High significance
Comments: Plants reproduce by seed and vegetatively and begin to bloom (seeds borne in capsules burst and fall to the ground after ripening) in July and continue until September or October with flowers pollinated by bees and butterflies (Bender, 1987; Czarapata, 2005), often with seed production by new plants in the same season (Uva et al., 1997). A single mature plant can produce 2.7 million seeds (Gutin, 1999). Flowers are tristylous and pollination restricted to crosses between the style of one length with stamens of the corresponding length. Purple loosestrife can also spread vegetatively by leftover pieces of plants and roots (ISSG, 2005). A single plant can produce more than 2 million seeds per year (Uva et al., 1997) with each stem (there are 1-50 per plant) producing as much as 100,000 to 300,000 seeds annually (Czarapata, 2005). Even so-called infertile cultivars produce viable seeds and can become invasive (Randall and Marinelli, 1996). Seed banking capability is very high as seeds remain viable for twenty years and can live twenty months submerged in water (Czarapata, 2005).

Subrank IV. General Management Difficulty: High

17. General Management Difficulty:High significance
Comments: Large populations extending over three acres or more are difficult if not impossible to completely eradicate so prevention is the best control measure (Bender, 1987; Czarapata, 2005). In such cases, prevention of expansion is the best management policy through hand pulling new plants along the periphery or herbicide spraying on plants extending beyond the main body of the population. For small infestations, eradication is possible with spot applications of glyphosate herbicides (Bender, 1987). Cutting and pulling also is effective (not mowing because it disperses seeds and fragments) on small infestations (<100 plants), just before flowering (Czarapata, 2005; ISSG, 2005), and plant materials should be dried and burnt before disposal. Use of golden loosestrife beetle (Galerucella calmariensis) and black-margined loosestrife beetle (Galerucella pusilla) as a biological control has been successful (Malecki et al., 1993; Sebolt and Landis, 2002) and these beetles pose little risk to nontarget plants such as crepe murtle because beetles can feed but cannot complete their life cycle on crepe myrtle (Schooler et al., 2003). Other biological control measures that have met with success are the root mining weevil (Hylobius transversovittatus) and a herbivorous weevil (Nanophyes marmoratus) (ISSG, 2005).

18. Minimum Time Commitment:High significance
Comments: A huge sum of money ($45 million) is spent each year on management of this species in the United States (Simberloff, 2003). Any control effort should be followed up the same growing season and for several years afterwards since some plants will be missed, new seedlings may sprout from the extensive seed bank, and a few plants will survive low dosage herbicide treatment (ISSG, 2005). Cost nationally is estimated in the several million dollar range annually to control this species and time commitment lengthy (Snyder and Kaufman, 2004). For small populations, frequent cutting of stems at ground level is effective somewhat but needs to be continued for several years and cut stems must be burned because plants resprout from fragments (Randall and Marinelli, 1996).

19. Impacts of Management on Native Species:Moderate significance
Comments: Herbicides should be used with caution given that loosestrife is restricted to wetlands, often covering
extensive acreage (Snyder and Kaufman, 2004). Glyphosate herbicides are non specific and tend to impact native species when used widely or when used in sensitive areas (ISSG, 2005). Use of golden loosestrife beetle and black-margined loosestrife beetle as a biological control has been successful (Malecki et al., 1993) and these beetles pose little risk to nontarget plants such as crepe murtle because beetles can feed but cannot complete their life cycle on crepe myrtle (Czarapata, 2005; Schooler et al., 2003). Gabor et al. (1996) found native species replaced adult purple loosestrife after its removal but purple loosestrife eventually reestablished dominance. Impact of root mining weevils on native, non-target species is also considered low (ISSG, 2005).


20. Accessibility of Invaded Areas:Low significance/Insignificant
Comments: It appears most to all areas are easily accessible, as for most aquatic plants outside unusual habitats such as caves or high elevation streams or ponds.
Authors/Contributors
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Management Information Edition Date: 01Nov1987
Management Information Edition Author: ORIGINAL VERSION (1987) BY J. BENDER; UPDATE BY JAY RENDALL

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

References
Help
  • Balogh, G. 1985. Ecology, distribution, and control of purple loosestrife in northwest Ohio. Annual report from October 1984-September 1985. Cooperative Wildlife Research Unit, Ohio State University.

  • Batra, S. W. T., D. Schroeder, P. E. Boldt, and W. Mendl. 1986. Insects associated with purple loosestrife (Lythrum salicaria L.) in Europe. Proc. Entomol. Soc. Wash. 88:748-459.

  • Bender, J. 1987. Element stewardship abstract for Lythrum salicaria. The Nature Conservancy, Arlington, Virginia. unpaginated.

  • Benson, A.J., C.C. Jacono, P.L. Fuller, E.R. McKercher, and M.M. Richerson. 2004. Summary Report of Nonindigenous Aquatic Species in U.S. Fish and Wildlife Service Region 5. Report prepared for U.S. Fish and Wildlife Service, Arlington, Virginia, 29 February 2004. 142 pp.

  • Benson, A.J., P.L. Fuller, and C.C. Jacono. 2001. Summary Report of Nonindigenous Aquatic Species in U.S. Fish and Wildlife Service Region 4. Report prepared for U.S. Fish and Wildlife Service, Arlington, Virginia, 30 March 2001. 60 pp.

  • Crow, G.E. and C.B. Hellquist. 2000. Aquatic and Wetland Plants of Northeastern North America. A Revised and Enlarged Edition of Norman C. Fassett's A Manual of Aquatic Plants. Vol. 1, Pteridophytes, Gymnosperms, and Angiosperms: Dicotyledons. University of Wisconsin Press, Madison, Wisconsin. 448 pp.

  • Crow, G.E. et C.B. Hellquist. 2000. Aquatic and wetland plants of northeastern North America, a revised and enlarged edition of Norman C. Fassett's A manual of aquatic plants. University of Wisconsin Press. 2 vol.

  • Czarapata, E.J. 2005. Invasive Plants of the Upper Midwest. An Illustrated Guide to Their Identification and Control. The University of Wisconsin Press: Madison, Wisconsin. 215 pp.

  • Deam, C. C. 1940. Flora of Indiana. Division of Forestry, Dept. of Conservation, Indianapolis, Indiana. 1236 pp.

  • Douglas, G.W., D. Meidinger, and J. Pojar, editors. 1999. Illustrated Flora of British Columbia. Volume 3. Dicotyledons (Diapensiaceae through Onagraceae). British Columbia Ministry of Environment, Lands and Parks, and British Columbia Ministry of Forests, Victoria.

  • Erskine, D.S. 1960. The Plants of Prince Edward Island. Publication 1088. Plant Research Institute, Research Branch. Canada Department of Agriculture.

  • Farnsworth, E.J. and D.R. Ellis. 2001. Is purple loosestrife (Lythrum salicaria) an invasive threat to freshwater wetlands? Conflicting evidence from several ecological matrics. Wetlands, 21(2): 199-209.

  • Fernald, M. L. 1950. Gray's manual of botany. 8th edition. Corrected printing (1970). D. Van Nostrand Company, New York. 1632 pp.

  • Fraser, L.H. and J.P. Karnezis. 2005. A comparative assessment of seedling survival and biomass accumulation for fourteen wetland plant species grown under minor water-depth differences. Wetlands, 25(3): 520-530.

  • Gabor, T.S., T. Haagsma, and H.R. Murkin. 1996. Wetland plant response to varying degrees of purple loosestrife removal in southeastern Ontario, Canada. Wetlands, 16: 95-98.

  • Gardner, S.C., C.E. Grue, W.W., Major III, and L.L. Conquest. 2001. Aquatic invertebrate communities associated with purple loosestrife (Lythrum salicaria), cattail (Typha latifolia), and bulrush (Scirpus acutus) in central Washington, USA. Wetlands, 21(4): 593-601.

  • Gleason, H. A. 1957. The New Britton and Brown Illustrated Flora of the Northeastern United States and Adjacent Canada. New York Botanical Garden, N. Y.

  • Gleason, H.A. 1952. New Britton & Brown. Illustrated Flora. Lancaster Press Inc. Lancaster, Pa. B52GLE01PAUS

  • Gutin, J.C. 1999. Purple passion. Discover, August 1999: 76-81.

  • Henderson, R. 1987. Status and control of purple loosestrife in Wisconsin. Research management findings, Number 4, Bureau of Research, Wisconsin DNR, Madison.

  • Invasive Species Specialist Group (ISSG). 2005. Global Invasive Species Database. Online. Available: http://www.issg.org/database (Accessed 2006).

  • Jackson, T. P. 1982. Purple loosestrife alert. U. S. Fish and Wildlife Res. Info. Bull. No. 82-24. Fort Collins, CO.

  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada and Greenland. Volume 2. Thesaurus. Deuxième édition. Timber Press, Portland, Oregon. 816

  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

  • Kartesz, J.T. 1996. Species distribution data at state and province level for vascular plant taxa of the United States, Canada, and Greenland (accepted records), from unpublished data files at the North Carolina Botanical Garden, December, 1996.

  • Katovich, E.J.S., R.L. Becker, and J.L. Byron. 2003. Winter survival of late emerging purple loosestrife (Lythrum salicaria) seedlings. Weed Science, 51: 565-568.

  • Mal, T.K., J. Lovett-Doust, and L. Lovett-Doust. 1997. Time-dependent competetive displacement of Typha angustifolia by Lythrum salicaria. Oikos, 79: 26-33.

  • Malecki, R.A., B. Blossey, S.D. Hight, D. Schroeder, L.T. Kok, and J.R. Coulson. 1993. Biological control of purple loosestrife. BioScience, 43: 680-686.

  • Meades, S.J. & Hay, S.G; Brouillet, L. 2000. Annotated Checklist of Vascular Plants of Newfoundland and Labrador. Memorial University Botanical Gardens, St John's NF. 237pp.

  • Mills, E.L., M.D. Scheuerell, J.T. Carlton, and D.L. Strayer. 1997. Biological invasions in the Hudson River basin. New York State Museum Circular, 57: 1-51.

  • Minnesota DNR. 1987. Contol and eradicaton of puple loosestrife. Unpublished paper prepared by the purple loosestrife program, November 1987.

  • Morrison, J.A. 2002. Wetland vegetation before and after experimental purple loosestrife removal. Wetlands, 22(1): 159-169.

  • Notestein, A. 1986. The spread and management of purple loosestrife (Lythrum salicaria L.) in Horicon National Wildlife Refuge, Wisconsin. M.S. Thesis, University of Wisconsin, Madison.

  • Randall, J.M. and J. Marinelli (eds.) 1996. Invasive Plants: Weeds of the Global Garden. Brooklyn Botanic Garden: New York. 111 pp.

  • Rawinsky, T. J. 1982. The ecology and management of purple loosestrife (Lythrum salicaria L.) in central New York. Master's thesis, Cornell University, Ithaca, New York.

  • Schooler, S.S., E.M. Coombs, and P.B. McEvoy. 2003. Nontarget effects on crepe myrtle by Galerucella pusilla and G. calmariensis (Chrysomelidae), used for biological control of purple loosestrife (Lythrum salicaria). Weed Science, 51: 449-455.

  • Sebolt, D.C. and D.A. Landis. 2002. Neonate Galerucella calmariensis (Coleoptera: Chrysomelidae) behavior on purple loosestrife (Lythrum salicaria) contributes to reduced predation. Environmental Entomology, 31(5): 880-886.

  • Shamsi, S. R. A. and F. H. Whitehead. 1974. Comparative eco-physiology of Epilobium hirsutum L. and Lythrum salicaria L. I. General biology, distribution, and germination. Journal of Ecology, 62: 279-290.

  • Shank, L.K. and J. Shreiner. 1999. Globally threatened calcareous riverside seep and calcareous riverside outcrop communities along the New Jersey shoreline of the Delaware River: Summary of rare plant census, community sampling, and recommended monitoring protocol. Department of Environmental Protection, Division of Parks and Forestry, Office of Natural Lands Management, Trenton, New Jersey. 220 pp.

  • Simberloff, D. 2003. Eradication- preventing invasions at the outset. Weed Science, 51: 247-253.

  • Skinner, K., L. Smith, and P. Rice. 2000. Using noxious weed lists to prioritize targets for developing weed management strategies. Weed Science, 48: 640-644.

  • Snyder, D. and S. R. Kaufman. 2004. An overview of nonindigenous plant species in New Jersey. New Jersey Department of Environmental Protection, Division of Parks and Forestry, Office of Natural Lands Management, Natural Heritage Program, Trenton, NJ. 107 pp. Online. Available: http://www.state.nj.us/dep/parksandforests/natural/heritage/InvasiveReport.pdf (Accessed 2005)

  • Snyder, J. W., E.C. Pilren, and J.A. Crawford. 1999. Translocation histories of prairie grouse in the United States. Wildlife Society Bulletin 27(2):428-432.

  • Stuckey, R. L. 1980. Distributional history of Lythrum salicaria (purple loosestrife) in North America. Bartonia 47:3-20.

  • Swink, F., and G. Wilhelm. 1994. Plants of the Chicago Region. Morton Arboretum. Lisle, Illinois.

  • Thompson, D. Q. 1991e. History of purple loosestrife (Lythrum salicaria L.) biological control efforts. Natural Areas Journal, 11(3): 148-150.

  • Thompson, D. Q. and R. L. Stuckey. 1980. Spread, impact, and control of purple loosestrife (Lythrum salicaria) in NorthAmerican wetlands. Unpublished report.

  • Thompson, D. Q., R. L. Stuckey, and E.B. Thompson. 1987. Spread, impact, and control of purple loosestrife (Lythrum salicaria) in North American wetlands. U.S. Fish Wildl. Serv., Fish Wildl. Res. 2. 55 pp.

  • Uva, R.H., J.C. Neal, and J.M. DiTomaso. 1997. Weeds of the Northeast. Cornell University Press: Ithaca, New York. 397 pp.

  • Weber, W. A. and R. C. Wittmann. 1992. Catalog of The Colorado Flora: A Biodiversity Baseline. University Press of Colorado, Niwot, CO.

  • Weihe, P.E. and R.K. Neely. 1997. The effects of shading on competition between purple loosestrife and broad-leaved cattail. Aquatic Botany, 59: 127-138.

  • Welling, C.H. and R.L. Becker. Seed bank dynamics of Lythrum salicaria L.: implications for control of this species in North America. Aquatic Botany, 38: 303-309.

  • White, D.J., E. Haber, and C. Keddy. 1993. Invasive Plants of Natural Habitats in Canada: An Intergrated Review of Wetand and Upland Species and Legislation Governing their Control. Report prepared for the Canadian Wildlife Service, Environment Canada. Ottawa, Canada. 121p. ISBN 0-662-20476-X.

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