collect and integrate plant occurrence data from disparate sources
provide centralized access to this data through a
variety of web interfaces
provide online visualization tools for this data
allow users to download as much of this data as possible
for their own analyses
The collection includes various
types of data -- herbarium specimen records, species lists compiled by
botanists for known locations, rare plant occurrences documented by the
Natural Diversity Database and the CNPS Inventory,
vegetation survey data from the California
Department of Fish and Game,
and plot species lists from sampling projects carried
out by land management agencies.
By providing ready access to all these types of occurrence data,
the project seeks
to facilitate research on questions related to biodiversity, ecology,
and conservation, and help researchers use the full power of their geographic
analysis and modeling tools.
When scientific names have changed,
the user can see both
the original name, and various current interpretations of the original name.
How Data is Assimilated
The intent is to provide a core set of data about each
observation and enough information for the user to select only those records
that are suitable for a given type of analysis.
Links are provided
data source for additional information whenever possible.
We examine source data sets and extract:
a plant name and a location
basic information about the site if available
the source institution and individuals responsible for the observation
the method used by the
observer or collector to identify this observation
(A description of the structure of the data is available here.)
By providing ready access to plant occurrence data, we seek to facilitate:
Access to range and distribution information for California plants
Analysis of patterns in plant distributions and species diversity
Protection of plant diversity at local scales
Protection of geographic range and genetic diversity of native species, both rare
There are many ways to participate in the Calflora project.
In an ongoing way, we need help with data entry
(online, mostly checklist and survey data),
photo editing (choosing photos for the Taxon Report pages),
quality control of the software (beta testing new applications),
and quality control of the data. With respect to
quality control, please inform us
if you see data that does not look quite right,
or use a Calflora application that does not function properly.
If you have plant occurrence data you would like to contribute, or would
like to participate in the Calflora project in some other way, please
When you see an observation of a plant at a certain
location on Calflora, does it mean that the
plant is (was) really there?
Because Calflora collects data from diverse sources,
each with their own strengths and weaknesses,
there is some filtering of the data which you (the user) must do
to make the best use of this data.
Here are some error conditions to watch out for:
- the plant is erroneously identified
- the record is incorrectly georeferenced (eg. the coordinates are not in the stated county)
- the plant in question was actually cultivated,
unknown to the observer or collector
Whenever possible, we try to identify such records
and, with the help of local experts, to label them as suspect.
This is an ongoing task, and new data continues to
come in. Meanwhile, here are several strategies for determining
the level of evidence for a plant at a location:
The presence of a plant in an area will be
reinforced by other nearby observations of the same plant.
Look at the number of records for a particular plant
in a particular area. As the observation database grows larger,
this becomes an increasingly effective technique.
For instance, if you see that there is only a single
record for a particular plant in the area of interest,
and it is far away from other observations of the
you may choose to discount it.
Some Calflora web applications are set up to enable this kind of filtering:
A Taxon Report page shows the number of observations per
From a Taxon Report page,
County Distribution Analysis
for a plant to see a county distribution map based on
more than one observation or more
than one source for each county.
In the What Grows Here?
application, if you set "Minimum Observation Count" to two
or more, you will eliminate single plant records from the plant list
for the target area.
Pay attention to documentation type,
which ranges from specimen (potentially the most
reliable), through documented and reported,
to literature (the least reliable).
A record is classified as literature, for instance,
when the observer is not known.
Pay attention to the individual observers
and collectors responsible for a record.
Some are more reliable at plant identification than others.