Bryolog 31 (25 February 2023)


As a general policy, check the website for event updates before you walk out the door!

  • Vote now regarding Chapter Board positions. This year, the Secretary and Field Trip Director positions are on the ballot. VOTE HERE
  • Only a few spots left for SO BE FREE 27, 23-26 June 2023, at the Sagehen Field Station in the Northern Sierra Nevada near Truckee, CA. Read the detailed announcement and register HERE

Timeless Bits

  • Survey Guidelines for Bryophytes and Lichens, by Jason Brooks, HERE
  • Calypogeia shevockii, by David Wagner, HERE
  • Photo Gallery: Gemma Jewels, HERE

Survey Guidelines for Bryophytes and Lichens

—Jason R. Brooks, California Academy of Sciences

Land managers have become increasingly interested in understanding and protecting bryophyte and lichen species within the state of California. Since adding bryophytes and lichens to the California Native Plant Society (CNPS) Rare Plant Inventory, managers now have valuable information as to the status of many of these species and are increasingly interested in protecting them whenever possible. It has become clear to CNPS by comments from agency personnel, as well as environmental consultants, that survey and reporting guidelines specific to bryophytes and lichens are needed, as survey and identification methods for these species can be quite different from those targeting vascular plants. This document is intended to serve as a companion to the CNPS Botanical Survey Guidelines ( specific to bryophytes and lichens and adds recommendations to help determine who should be considered qualified to perform surveys, how and when to perform the field work, and reporting guidelines.

Many botanists are unfamiliar with the taxonomy of bryophytes and lichens, and therefore, have little knowledge or experience of where to begin to search for and subsequently identify members of these groups. In a majority of cases, collection of specimens is necessary not only to detect rare species, but also for confident identification, as compound microscopy is required to identify many bryophytes to species, and chemical tests are required for many lichens. Experience surveying for and identifying these taxa are crucial to a successful and enlightening survey effort. The following guidelines should be used by surveyors who perform these surveys in the field:

  1. Qualifications
    1. At least some type of formal training in the field of bryology and lichenology. Training could either be university course work or workshops given by CNPS bryophyte chapter or other similar entity.
    2. Surveyors should have a working knowledge of bryophyte and lichen taxa within a given survey area, at least to the level of genus.
    3. A general familiarity with proper techniques for collecting specimens in the field.
  2. Survey Timing
    1. A common misconception is that the best time of year to survey for bryophytes is in the winter as this is when they ‘green up’ and are showy. Though the latter is true, the former is not. Often bryophytes have more definable field characters in a dehydrated state, making surveys for bryophytes, as well as lichens, easily done in summer and fall months. An exception to this is the ephemeral species, which like annual vascular plants, appear for only a short period of time and are then gone until the following year. These species often appear in winter months at lower elevations, early spring at middle elevations, and early summer at high elevations. If target taxa are within this group, then survey timing must be adjusted accordingly.
  3. Survey Methods
    1. Desktop reviews of survey areas are always the first step in any plant survey. Typically, the California Natural Diversity Database’s RareFind application ( and CNPS’s Rare Plant Inventory ( are queried to determine which, if any, rare plant species have been recorded within a particular area. Other useful resources when surveying for bryophytes and lichens are the Bryophyte Portal ( and Lichen Portal ( These online resources can provide mapped locations not only for specimens in the given survey area, but throughout the region or the world. This can be useful to further understand the approximate distribution of a particular species of interest.
    2. A knowledge of the special habitats and substrates preferred by these taxa is crucial to determining the best field methods. Unlike many vascular plants, rare taxa within these groups can be corticolous (bark dwelling), saxicolous (rock dwelling) and/or terricolous (soil dwelling). For example, surveying for these species will sometimes require searching the trunks and/or branches of many trees, or boulders along a creek, or cliff walls for species associated with these habitats. Habitats for many rare species are extremely specific, therefore the microhabitat should be well understood so as not to spend fruitless time searching areas not likely to harbor the target taxa. Reference site visits are highly recommended, even if only to give an idea of the habitat of a particular species.
    3. The only reasonable survey method for bryophytes and lichens includes intense sampling of preferred habitats that may contain rare taxa. For example, if the target of a survey is a rock-loving species typically found on south-facing rock outcrops, the surveyor would attempt to collect a representative set of voucher specimens within the appropriate habitat, to be identified later to determine if the target species is present. In some cases, it will be impossible to determine this in the field, as many bryophytes and lichens species have look-alike taxa that are nearly impossible to differentiate without further review in the lab.
  4. Collecting Methods
    1. A detailed description of how to collect bryophytes as well as voucher packet templates can be found at the CNPS Bryophyte Chapter website ( In general, guidelines state that no more than 20% of a population of a particular species should be collected within 10 meters of the spot the surveyor is standing. With bryophytes, collected material should prioritize the collection of mature sporophytes; however if sporophytes are not present, material should still be collected as they are often not necessary for identification of species. Collected specimens should be placed into voucher packets with collection number, location and substrate data written onto the packet containing the specimen, or written into a field notebook and transferred to the packet at a later date. In addition, if enough material is available, a voucher packet should be created. This would be roughly enough material to cover the palm of one’s hand. Sometimes a population is too small to collect this amount of material and in these cases the surveyor would collect only a small amount. It is highly recommended that these packets be sent to local public herbaria, with completed herbarium labels attached.
    2. Collecting bryophytes and lichens can be tricky, as they are small and sometimes stubbornly attached to the substrate upon which they grow. It is handy to have a tool such as a paint scraper or the blade of a knife to remove them. Collecting an intact thallus, or a ‘moss clump’ in the case of bryophytes, ensures a specimen that is not shattered or damaged and can further aid in identification.
  5. Identification
    1. Identification of bryophytes and lichens can be time consuming and difficult. Specimens should be identified at least to the point to determine whether the specimen is of conservation concern. Often this means only identifying the specimen to genus, but on some occasions requires the specimen to be identified to the species level. It is highly encouraged that all specimens found be identified to species to the extent possible. Identifying all species found in a particular area is important, as new species are still being discovered. In addition, range extensions can also be found; some of these will be new to the state of California and by default considered rare and of conservation value.
    2. Many rare species will require an expert to identify. With both bryophytes and lichens this can be due to several factors which include chemical tests, or species for which current keys are either not available or are not particularly useful. In addition, some species were originally described from a small geographic area or are based on very few specimens. In these cases, often the range of variability is not well represented in the literature, creating confusion when atypical specimens are collected.
  6. Reporting
    1. Because bryophyte and lichen surveys will generally accompany a vascular plant survey, reporting guidelines are the same as those for vascular plants and can be found in the CNPS Botanical Survey Guidelines in section 5.

CNDDB. 2023. RareFind 5. Accessed at:
CNPS. 2001. CNPS Botanical Survey Guidelines. Accessed at:
CNPS. 2023. Rare Plant Inventory. Accessed at:
CNPS Bryophyte Chapter. 2023. Collecting protocols. Accessed at:
Consortium of North American Bryophyte Herbaria. 2023. Accessed at:
Consortium of North American Lichen Herbaria. 2023. Accessed at:

Calypogeia shevockii

Calypogeia shevockii

To purchase David Wagner’s Guide to Liverworts of Oregon in its entirety on flash drive, email

Photo Gallery: Gemma Jewels

In this issue, we are highlighting the beauty and wonder of gemmae, specialized asexual propagules produced by many moss and liverwort species. Gemmae come in a wide assortment of shapes and sizes, and may be generated on leaves, stems, rhizoids, or in dedicated structures like gemmae cups. They may be dispersed by wind, water, animals, or plain old gravity, and upon landing in a suitable habitat, presumably could develop into a new but genetically identical plant, perhaps with a somatic mutation or two thrown in. Savor a few morsels of these adorable packets of totipotent cells in the following photos from our members.

leaf with gemmaeleaf with gemmae, better lighting
Gemmae on Didymodon rigidulus var. rigidulus leaf, CC BY-NC John McLaughlin


habit shot of mossclose up of gemma
Gemmabryum barnesii with gemmae in leaf axils (left); gemma with leaf primordia (right). CC BY-NC Amanda Heinrich


habitmicroscopic view of gemma
Blasia pusilla flask with gemmae (left); gemma (right). CC BY-NC David Wagner


liverwort habitclose up of gemmae
Cephaloziella divaricata with gemmae on leaf tips (left); Cephaloziella divaricata two-celled gemmae on leaf tip (right). CC BY-NC David Wagner


cup filled with green disks
Marchantia latifolia gemmae cup with gemmae. CC BY-NC David Wagner


David Wagner’s photos are from his Guide to Liverworts of Oregon. To purchase his book on flash drive, email

For a more in depth discussion of gemmae with countless photos, check out Janice Glime’s excellent online Bryophyte Ecology ebook:

To suggest a topic and/or contribute photos to future galleries, please email


Post A Comment