How to Use CalWeedMapper

CalWeedMapper is designed to inform strategic management planning at a landscape level. Quad data shows where each plant currently exists in the state, where it is spreading, and where it is currently under active management. Suitability data shows where a plant is most likely to be able to spread. For a particular plant and region, CalWeedMapper identifies management opportunities in three categories as determined by the species’ spatial distribution: surveillance, eradication or containment.

Surveillance opportunities: when a plant is not found within the region, but is found within 50 miles. The proximity of neighboring populations and the suitability of the region can inform an assessment of the likelihood of establishment. Regular surveillance is important for early detection.

Eradication opportunities: when a plant exists in the region but only in small isolated populations. The spatial pattern for eradication is 1 infested quad surrounded by at least 2 concentric bands of absent quads. The size and isolation of populations and the suitability of the region can inform an assessment of the strategic importance and feasibility of eradication.

Containment opportunities: when a plant exists in the region and is too widespread for eradication. The strategic importance and feasibility of a containment opportunity can be further assessed based on how distinct the boundaries of the infestation are, how isolated it is, and the suitability of the surrounding area.

While each plant is listed in only one category for a given region, multiple management approaches can be appropriate within the region. Planning particular management measures requires additional analysis and field mapping.

CalWeedMapper generates two types of reports: a Regional Management Opportunity Report and a Regional Species Map Report. These reports provide a starting place for establishing priorities and goals at the regional level.

Regional Management Opportunity Report:

This report provides a table of all plants that present opportunities for surveillance, eradication, or containment in the region selected. The table summarizes each plant’s distribution and suitability in the region. Plant species are organized by their statewide rating in Cal-IPC’s Inventory, but impacts can vary by region.

Regional Species Map Report:

This report provides a map for a particular species in the region selected. The map illustrates the plant’s spatial distribution in the region. Suitability maps compare current suitability with projected suitability in the year 2050, which may affect decision-making on management for the plant.

See About for information on methods. See ? on the Maps page for instructions on using the mapping tool.