From 2003-2018, digitizing efforts resulted in the inclusion of over 2 million specimen records in the original Consortium of California Herbaria (CCH) portal, sixty-five percent of which were georeferenced (provided with geographic coordinates). In 2018, the Consortium of California Herbaria Portal 2 (CCH2) was established to serve data for all specimens housed in CCH member herbaria. An additional million herbarium specimens are being imaged, digitized and georeferenced due to the work of the California Phenology Thematic Collections Network (CAP-TCN; These amazing accomplishments have made herbarium data available to a broad array of researchers including those studying climate change and developing conservation plans.

The Consortium of California Herbaria Portal 1 (CCH1) is an updated version of the original CCH portal. CCH1 is now a specialized portal that includes highly curated records for all California vascular plants from both Consortium members and other data portals worldwide.

When seeking to understand a taxon's range, we now have the ability to computationally combine two lines of evidence, the description of the taxon's range provided in the Jepson eFlora and the distribution of georeferenced, California specimens that bear that taxon's name (and known nomenclatural synonyms). The CCH1 portal uses these two sources of data in innovative ways to enhance the usefulness of herbarium specimen databases. For example, specimens are mapped in CCH1 with three different color icons. Yellow icons or "yellow flags" are georeferenced specimens outside the range published in the Jepson eFlora. Blue icons represent specimens mapped within the expected range. Lastly, purple icons represent specimens collected from plants in cultivation. Cultivated specimens are flagged separately because they may otherwise be mapped with yellow icons. The garden where the specimen was planted may be located far outside the normal range of the species. The processes for generating these flags are described in the two sections below.

Yellow Flags

When mapped, most georeferenced specimens fall within the taxon range described in the Jepson eFlora. However, about 6% of them show incongruence — the georeferenced location for a specimen falls outside of the distributional range of the taxon as it is described in the Jepson eFlora. These records are tagged (in both the CCH1 and Jepson eFlora) with a "yellow flag" icon.

There are several reasons that specimen coordinates might be at variance with the distribution published in the Jepson eFlora. The most frequent circumstances that generate yellow flags include:

Needing to revise range statements in the Jepson eFlora

For example, consider the taxon Xylococcus bicolor. In the original printing of The Jepson Manual, Second Edition, X. bicolor did not have the Peninsular Ranges Subregion (PR) indicated as part of its range, but yellow flag analysis revealed a large number of X. bicolor specimens collected from PR (left image). The yellow flagged records were resolved, in large part, by author confirmation to add PR to the distribution string of X. bicolor in the Jepson eFlora (right image). The addition of PR was based on the confirmation of specimens at UC/JEPS and RSA.

  Map of X. bicolor specimens in southwestern California, with yellow flags based on the original X. bicolor range statement.

Updated map after the Peninsular Ranges Subregion (PR) was added to the X. bicolor range statement, resolving yellow flags.

Incorrect georeferencing or typos in label coordinates

Latitude or longitude might be incorrectly recorded, converted, or transcribed. The location of the record might have been recorded incorrectly or inferred erroneously. These can often be corrected by examining the data without looking at a specimen.

Mapping or other software errors

Very small region units such as pieces of DMtns or offshore islets are not represented well by the yellow-flag process and consequently result in false positives. Records with locations close to boundaries are troublesome.

Misidentification or unincorporated taxonomic revisions

The specimen might have been incorrectly keyed out or mismatched with a picture initially, or there might have been a taxonomic revision subsequent to the initial identification.

Names with 100+ yellow flags

We invite all botanists to join the effort to help resolve these incongruences. We are especially interested in recruiting field botanists with first-hand knowledge of plant distributions and herbarium botanists with collections that can help resolve questions about a taxon's distribution. Resolving "yellow flags" will forward two goals: (1) making herbarium data as accurate as possible and (2) using georeferenced voucher specimens to improve the description of taxon ranges included in the Jepson eFlora.

In some cases, it is difficult to make inferences based on the information in online databases alone; specimens (at any herbarium) may need to be consulted. Comments regarding individual specimens may be submitted directly through the CCH2 portal.

If you would like to help investigate yellow flags or comment on the development and use of these pages, please contact Jason Alexander (

Purple Flags

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