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Updated March 17, 2020    
Calflora provides a specialized mapping platform for plant locations as a public service. This platform consists of 1. a geospatial database, and 2. a set of web applications and phone applications.

There are many ways to get data into the database. Data can be extracted from the database in several formats. The web applications provide many ways to visualize the data. While originally developed to track native plant populations, the platform has also been used to advantage to track non-native populations.

The California Invasive Plant Council (Cal-IPC) and other organizations engaged in weed management have used Calflora's platform to collect and map weed data across California since 2008. This page describes the ongoing effort.

If you are interested in participating, either by contributing weed observations or by monitioring weed observations contributed by others, read on. Note that most Calflora tools can be used without charge, including support by email and phone.

For more information, please contact Calflora support.

 Conium maculatum

Monitoring Weed Observations
Calflora Search Applications
The Observation Search application (OS) is useful for searching for weed observations. You can search for all non-native plant observations in an area, or limit the search to plants on a particular list. An OS search can be saved and shared with others, used as the basis of an email alert, or loaded into the phone applications.

The Plant Distribution application is useful for seeing the statewide distribution of a particular plant. Zoomed close, this application can show line and polygon records of the plant. There is a link to Plant Distribution on each Taxon Report page; as an example, here is Plant Distribution for Acacia dealbata.

The What Grows Here? application (WGH) is useful for searching for all plants in an area. You can also use it to juxtapose the locations of two or more plants on the same map, each with their own colored icon. For instance, here are locations of Centaurea calcitrapa and Centaurea solstitialis in Sonoma Co.

Cal-IPC's CalWeedMapper web application lets you create reports of invasive plant distribution, and supports prioritization of invasive plants for a user-defined region. The tool includes all invasive plant species from the Cal-IPC Inventory. Weed data published on Calflora are forwarded daily to CalWeedMapper.

Regional Priorities for Invasive Plant Management
Cal-IPC is working with regional partners to set landscape-level strategies and to build a coordinated statewide approach for the early detection and eradication of invasive plants.

Priority plant lists (eradication and surveillance targets) have been developed for several regions. You can access these plant lists (and the corresponding saved searches) from the Regional Priorities group home page.

Email Alerts
The Regional Priorities group is open to anyone. Once you join the group, you can utilize one of these regional saved searches as an email alert: whenever any new records of the target plants appear in the region, you will be notified by email.

To add an email alert, go to My Calflora / Alerts, select a saved search, and choose whether you want the alert weekly or monthly.

You can also do your own search in Observation Search, save it by name, then go to My Calflora / Alerts add it as an email alert.


Observation Search

What Grows Here?

Regional Priorities
group home page

My Calflora / Alerts

Contributing Weed Observations
Calflora provides various methods to contribute plant observations to the database, described on the Contributing Plant Observations page.

In the Calflora model, each data contributor has their own account, and is responsible for their own observation records. The My Observations application allows you to manage and edit your own records.

When several data contributors need to work closely together, they can start or join a group. Groups are explained further on the About Groups page. Groups are a mechanism for collaborating between contributors. If you put your record into a group while it is still unpublished, then the people in that group will be able to see it and comment on it, and people outside the group will not. (Once a record is published, all Calflora users will be able to find it whether is is in a group or not.)

    There is also a social aspects of groups: when you add an observation to a group, the other members of the group will likely find out about it, either from an email, by looking at group activity, or by doing a search. Seeing your record may encourage other members to add addional records of their own.
If you are interested in contributing observations of weeds, there are two long-standing Calflora groups you might consider joining: Early Detection Network, and Weed Observations. The Early Detection Network group is focused on early detection target weeds in various areas. The Weed Observations group is focused on documenting the range and intensity of all weeds.

About Groups

Early Detection Network
group home page

Weed Observations
group home page

Calflora's Weed Manager
Weed Manager is a system allows organizations engaged in land management to track weed infestations and treatments over time. Calflora developed this system in close collaboration with agencies collecting weed information to ensure that it met their needs. Features include customizable data collection forms, and detailed reports for management.

Weed Manager is available to subscribing agencies for an annual fee. Over a dozen agencies across the state are now using Weed Manager.

The Early Detection Network is a Weed Manager group which any Calflora user can join without cost. Members of this group are able to try out some of the features of the Weed Manager system. It has three projects:

Weed Manager

Early Detection
What makes a weed stand out as an early detection target in a certain area? In broad strokes, it is a combination of high potential impact, low current distribution, and high feasibility of control.

While the Bay Area Early Detection Network (BAEDN) was active, Calflora worked to support their efforts to collect observations of plants on the Bay Area Early Detection Weeds list. How the BAEDN folks came up with their list is fascinating, and is described in detail in this article.

Once the BAEDN list was made public, it had the effect of catalyzing the data collection efforts of many individuals and agencies in the Bay Area. As a result, we know much more now about where those weeds are growing and spreading in Bay Area counties.

For instance, there were 20 records of Rytidosperma penicillatum (purple awned wallaby grass) reported in the Bay Area before June 1, 2011. Since that date, an additional 1150 records have been reported in the Bay Area. As it turned out, this weed is much more widespread than expected, so widespread that it does not really qualify as an early detection target. But, nobody knew how widespread it was before the data collection effort inspired by the BAEDN list.

© 2010 Robert Steers/NPS

Choosing Target Weeds
In 2009, when Andrea Williams worked for the National Park Service, she wrote the following in her description of a volunteer based protocol (Early Detection of Invasive Plant Species in the San Francisco Bay Area Network):
    "The list of target species for each park was based on current knowledge and rankings, summing recognized invasiveness and biological ease of control and stratifying into priorities by feasibility of control based on species' infested acreage in the park." (pg. xvii)
A recent National Park Service Resource Brief further explains the protocol: exotic plants on SFAN land are classified into four lists, from high to low priority. The point of invasive plant early detection is to "... find potentially problematic invasive plants ... while they can still be easily controlled ...". Collecting adequate data is fundamental, and is used
  • To determine the distribution and abundance of target invasive plant species
  • To measure the success of removal activities
  • To understand how different invasive plants threaten local ecosystems
  • To re-prioritize which species and locations to target on future surveys
  • To determine the factors that lead to new infestations
Invasive Plant Early Detection
San Francisco Bay Area National Parks