Spread, Impact, and Control of Purple Loosestrife (Lythrum salicaria) in North American Wetlands


Pump house and water control structure for green-tree impoundment at Montezuma National Wildlife Refuge in central New York. Waterfowl broods produced in adjacent flooded forest found excellent foraging conditions among floating and emergent aquatic plants in the foreground, 18 June 1968.		Ten years later, purple loosestrife had displaced native food and cover plants in the waterway surrounding the green-tree impoundment at the Montezuma Refuge. Biologist holding stadia rod in middle foreground is obscured by mature plants. Note the abundance of Lythrum salicaria seedlings along the water line, 16 August 1978.

Daniel Q. Thompson, Ronald L. Stuckey, Edith B. Thompson

United States Department of the Interior
Fish and Wildlife Service
Washington, DC

Introduction

Purple loosestrife (Lythrum salicaria L.) is an erect, herbaceous perennial of Eurasian origin that became established in the estuaries of northeastern North America by the early 1800's. By the late 1800's it had spread throughout the northeastern United States and southeastern Canada, reaching as far north and west as Manitoba. L. salicaria caused few problems until the 1930's when it became aggressive in the floodplain pastures of the St. Lawrence River. Since then, it has steadily expanded its local distribution and now poses a serious threat to native emergent vegetation in shallowwater marshes throughout the northeastern and northcentral regions. Recent records indicate that purple loosestrife is also tolerant of soils and climates beyond these regions and threatens to become a serious problem in wetlands and irrigation systems in the Great Plains and the Far West.

It is no small irony that after 50 years of struggle to find some means of breaking up monotypic stands of cattails (Typha spp.) to increase wildlife diversity and abundance, wetland managers must now cope with a foreign species that replaces cattail, but unfortunately creates another monospecific community of greatly diminished wildlife value.

Figures

Figure 1 -- Structure, growth forms, and field identification characters of Lythrum salicaria (purple loosestrife).
Figure 2 -- Distribution of purple loosestrife, broad-leaved cattail, and reed canarygrass in the Northern Hemisphere.
Figure 3 -- Adventitious shoots of purple loosestrife after a flash flood.
Figure 4 -- Adventitious shoots of purple loosestrife on a mat of floating vegetation.
Figure 5 -- Establishment and early spread of purple loosestrife by 1880.
Figure 6 -- Spread of purple loosestrife as of 1900.
Figure 7 -- Distribution of purple loosestrife as of 1940.
Figure 8 -- Distribution of purple loosestrife as of 1985.
Figure 9 -- Hectares of land under irrigation on FRP from 1906 to 1980.
Figure 10 -- Purple loosestrife in Idaho.
Figure 11 -- Purple loosestrife in Wyoming.
Figure 12 -- Latilong blocks occupied by purple loosestrife in NY, MI, WI, and MN from 1840 to 1980.
Figure 13 -- Purple loosestrife in New York.
Figure 14 -- Estimated biomass dike cover made up by purple loosestrife on the Montezuma NWR.
Figure 15 -- Purple loosestrife seedling.
Figure 16 -- Purple loosestrife seedlings due to muskrat foraging.
Figure 17 -- Purple loosestrife in Nebraska.
Figure 18 -- Wild hay harvested in 1974 in the northern United States.
Figure 19 -- Purple loosestrife status in North American wetlands as of 1980.

Tables

Table 1 -- Percent frequency of occurrence of wetland species associated with purple loosestrife.
Table 2 -- Schedule and cost of 10-year biological control program for purple loosestrife.
Table 3 -- Area of four wetland types in the northern Atlantic and Mississippi flyways.
Table 4 -- Muskrat fur harvest and honey sales from northern Atlantic and Mississippi flyways.
Table 5 -- Benefit-cost analysis of resources and values at risk to purple loosestrife infestation.
Table 6 -- Number of colonies of bees and value of honey in the top 10 honey-producing states.
Table 7 -- Purple loosestrife infestation classes.

NOTE: Use of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Government.

Fish and Wildlife Research - This series comprises scientific and technical reports based on original scholarly research, interpretive reviews, or theoretical presentations. Publications in this series generally relate to fish or wildlife and their ecology. The Service distributes these publications to natural resource agencies, libraries and bibliographic collection facilities, scientists, and resource managers.

Copies of this publication may be obtained from the Publications Unit, U.S. Fish and Wildlife Service, Washington, DC 20240, or may be purchased from the National Technical Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161.

As the Nation's principle conservation agency, the Department of the Interior has responsibility for most of our nationally owned public lands and natural resources. This includes fostering the wisest use of our land and water resources, protecting our fish and wildlife, preserving the environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department assesses our energy and mineral resources and works to assure that their development is in the best interests of all our people. The Department also has a major responsibility for American Indian reservation communities and for people who live in island territories under U. S. administration.

This resource is based on the following source:

This resource should be cited as:

Thompson, Daniel Q., Ronald L. Stuckey, Edith B. Thompson. 1987. Spread, Impact, and Control of Purple Loosestrife (Lythrum salicaria) in North American Wetlands. U.S. Fish and Wildlife Service. 55 pages. Jamestown, ND: Northern Prairie Wildlife Research Center Online. http://www.npwrc.usgs.gov/resource/plants/loosstrf/index.htm (Version 04JUN1999).

Daniel Q. Thompson*, 623 Del Norte Place, Fort Collins, Colorado 80521.
Ronald L. Stuckey, Department of Botany, The Ohio State University, 1735 Neil Avenue, Columbus, Ohio 43210.
Edith B. Thompson, 623 Del Norte Place, Fort Collins, Colorado 80521.

* Wildlife Editor (retired), Editorial Office, U.S. Fish and Wildlife Service, Colorado State University, Fort Collins, Colo. 80523.

Downloading Instructions -- Instructions on downloading and extracting files from this site.

loosstrf.zip (919K) -- Spread, Impact, and Control of Purple Loosestrife (Lythrum salicaria) in North American Wetlands

Installation: Extract all files and open index.htm in a web browser.

Spread, Impact, and Control of Purple Loosestrife (Lythrum salicaria) in North American Wetlands

Introduction

Table of Contents

Figures

Tables