This web site should allow anyone with internet access to find purple loosestrife infestations anywhere in Wisconsin. This is important for loosestrife control work and, especially biological control because a local source of purple loosestrife rootstocks is required for rearing leaf beetles and release sites with suitable characteristics for those beetles must also be found.

In the future, we hope to include WDNR beetle release sites on the map, with timely information about which of these might have collectable leaf beetles on them so that inexpensive beetle rearing stock will be locally available. We also want to make it possible for individuals to send in information on new purple loosestrife infestation sites, as well as their own beetle release sites. Look for these changes soon.

This web site's map shows all the purple loosestrife infestation sites in the WDNR's mid-1980's statewide survey of the plant. Sites are located generally by proximity to roads, lakes and watercourses. County lines are also shown on the map. Detailed written information for each infestation site is available by zooming in to the site(s) of interest and bringing up location data in a box at the bottom of the web page, as outlined below.

  1. Access the site at
  2. Access the purple loosestrife info by scrolling down to and clicking on "Purple Loosestrife Distribution and Control".
  3. Draw a box around any smaller area of particular interest. (If this does not work, first click on the zoom in icon on the left side of the page.)
  4. If the level of detail is not fine enough to see individual sites of interest, draw another box encompassing just them.
  5. Make the active layer (the layer of information that will be highlighted) "purple loosestrife" by clicking on the empty circle in front of "purple loosestrife" on the right side of the page. (If a map "Legend" appears here instead of a "Layers" list, you must click on the uppermost icon in the left column on the left side of the page until "Layers" appears on the right side of the page.)
  6. Back in the list of icons on the left side of the page, click on the icon second from the bottom in the right column to highlight location data for the points on the map.
  7. Read the data for the sites shown on the map in the box at the bottom of the page. The data are usually township, range, section and, sometimes, quarter section* information and will identify the specific area on any USGS topo map or in the Wisconsin Atlas and Gazetteer where that site exists. Some data in latitude and longitude coordinates may eventually be added for some points.

*Wisconsin is divided into townships that are approximately square and 6 miles on each side, labeled by township numbers running north and south, and range numbers running east and west. Thus, "R" numbers along the bottom of a map show range (e.g., R 12 E) and "T" numbers along the sides of a map show townships (e.g., T 16 N). Find the township that intersects both these numbers, given in the bottom box of data for any area, and you will identify the township where that area is found. Each township is divided into 36 1-mile squares, called sections, and numbered from 1 to 36, starting from 1 in the upper right corner of the township and ending with 36 in the lower right corner. The section number identifies which of these contains the plants. If a quarter section is also identified, it will be the area of that section with the plants. Thus, the finest resolution of this township/range system is a quarter section, or about 160 acres. To determine the exact location of the loosestrife, find a likely local map location therein and explore it on foot. In the future, sites should be located with Lat/Long data that are more exact & easier to use with GPS.

EXAMPLE: Site #19872329 is at "26N6E19" and "NE". This means the site is in Township 26 North, Range 6 East, Section 19, in the northeast quarter of that section. (Note the additional site details giv

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