Michigan Sea Grant

Activities: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10

Activity Four
Is Purple Loosestrife a Problem Near Our School?

Objectives
Students will cooperate to prepare a comprehensive map showing the distribution of Purple loosestrife in the school district area and collect other data relevant to its distribution and control.

Methods
Each student will locate as many patches of purple loosestrife as possible in the area surrounding his/her residence and fill out a standard form which can be used to plot the distribution and density of the species for the school district area. The location of loosestrife stands are marked on a large road map of the district with the color of the push pins representing the percentage of ground covered by the plants.

Background
In order to devise a comprehensive plan for the control of purple loosestrife in wetlands, it is necessary to know the location of stands, their extent and density. Different means of control may be used depending on the size of stands and their density. In very small stands with low densities of plants, control may be a matter of pulling the plants before setting seed for several years in a row. In other situations, weed killing chemicals may be practical. In the thickest of stands, biological controls may be the best method.

Materials
Large school district map, such as that used by the school bus system showing street names, roads and water bodies. A box of push pins with heads of at least four colors. Standard forms (to be developed) to record information on loosestrife stands. One or more USGS topographic maps covering the same area as the road map on which to compile and accurately locate the distribution of the plants.

Procedure
Obtain a large school district map from the bus garage, transportation supervisor or school district office. After discussing the loosestrife problem and teaching students to identify the plant, distribute several record cards with fields for recording information about stands of loosestrife. Students will take these home and attempt to locate all of the existing stands of purple loosestrife within a 1 km radius of their home. The student will fill out one card for each distinct stand of the plant, listing the location of the stand, approximate size, density of plants and other information obtained. A small sketch map on the reverse side of the card may be useful in precisely locating the stand and its size. Data from the record cards is then plotted on the wall map and a master topographic map of the school area. Additional information extracted from the cards can be charted or used to construct tables and graphs.

Extensions
Other wetland species, such as cattails, sedges, willows, etc. could be mapped at the same time on the same map by using other colors of push pins or different head sizes. Or each species could be mapped on separate acetate overlays to fit over the map. The distribution of species could be compared to a soils map of the same area, obtainable from the county extension office. Photos of areas mapped could be placed around the map and connected to their location by colored strings.

Evaluation
Students may be asked to generate testable hypotheses relating to the distribution shown by the maps. They may be asked to make predictions about areas that might be next to be invaded by loosestrife. The number and quality of record cards submitted could be used in assigning extra credit or contributing to the marking period grade.

Activities: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10


11/10/2008
Michigan Sea Grant promotes greater knowledge of the Great Lakes through education, research and outreach.
© Michigan Sea Grant.