Viridothelium virens
|
LICHENS |
Cladonia coniocraea
|
We DO NOT encourage people to collect lichens, which are part fungi. Photograph and study lichens, but leave them be. Lichens are extremely slow-growing and even a small one could well be decades old. A good reason NOT to collect them. In addition, many lichens need to be examined under a microscope to identify. The rock-growing ones often need a rock hammer to collect them.
Some of our members are knowledgeable enough to responsibly collect and study lichens, with the necessary permits, so you may see lichens at our foray collection tables (or on NJMA Foray Reports). When you do, look at the lichen specimens and examine them. In springtime, consider attending a NJMA Lichen Walk to learn more about lichens. These walks have attendance size limits and fill up quickly.
Some of our members are knowledgeable enough to responsibly collect and study lichens, with the necessary permits, so you may see lichens at our foray collection tables (or on NJMA Foray Reports). When you do, look at the lichen specimens and examine them. In springtime, consider attending a NJMA Lichen Walk to learn more about lichens. These walks have attendance size limits and fill up quickly.
What is a Lichen?
Lichens are composite organisms that primarily contain a fungus (mycobiont) and a photosynthetic organism (photobiont). The photobiont consists of an alga and/or a cyanobacteria. In about 74% of lichen species, the photobiont consists of only green algae. In approximately 21% of lichens, the photobiont is only cyanobacteria. The remaining 5% of lichens contain both green algae and cyanobacteria (Hinds, 2007). Those proportions likely vary by habitat type and region. Cyanolichens, or lichens containing cyanobacteria instead of algae, are easily identified as such by their dark blue-green or blue-gray layer, or by their dark, jelly-like form when wet (Brodo, 2001).
There are many more species of lichen-forming (or lichenized) fungi than there are photobionts (either algae or cyanobacteria). Because of this, different species of lichen can have the same species of photobiont. Additionally, individuals of the same species of lichen can have different species of photobiont, especially across the lichen’s geographic range. Thus, lichens are classified and defined by their mycobiont and are officially considered a type of fungus, despite their composite nature.
Trebouxia is the genus of green algae most commonly found in lichens. For many years, it was thought that Trebouxia could only rarely be found free-living in nature. However, a study by Mukhtar et al. (1994) found that free-living Trebouxia were among the first colonizers of rocks in an area following fire. Other recent studies also suggest that free-living Trebouxia exists in quantities high enough for lichen spores to form a new lichen if both land on a suitable substrate (Hinds, 2007). Trentepohlia, Coccomyxa, and Stichococcus are some other common genera of green algae that can become lichenized. Photobionts are not easy to identify beyond genus without isolating them from their mycobiont, and less than 5 percent of lichens have had their photobionts identified to species level (Brodo, 2001).
Cyanobacteria belong to an entirely different kingdom than the green algae. The most common genus is Nostoc, found mostly in jelly lichens (Collema and Leptogium), and in many species of Peltigera. All cyanobacterial photobionts can be found free-living in nature (Brodo, 2001).
Recent discoveries using molecular technologies and DNA analysis suggests lichens are better described as ecosystems rather than composite organisms. Hawksworth and Grube (2020) explain, “A lichen is a self-sustaining ecosystem formed by the interaction of an exhabitant fungus and an extracellular arrangement of one or more photosynthetic partners and an indeterminate number of other microscopic organisms.” Meaning, in addition to the photobiont and mycobiont, lichens also contain other fungi (mycobiome) and bacterial colonies (microbiome). And, as if that wasn’t complex enough, protists and viruses have also been known to associate with lichens.
Lichenization has evolved independently multiple times along different lineages in the fungal kingdom. Lichens do not all form a single clade where they are all related to one another; they are polyphyletic. Lichens are often described as a “life-style”, an evolved strategy of (simply put) farming photobionts as a means of obtaining food, just like other fungi form mycorrhizal relationships with the roots of living plants, or obtain nutrients from dead or decaying organic matter (saprophytes), or parasitic fungal pathogens (wilts, blights, and other necrotrophs).
There are many more species of lichen-forming (or lichenized) fungi than there are photobionts (either algae or cyanobacteria). Because of this, different species of lichen can have the same species of photobiont. Additionally, individuals of the same species of lichen can have different species of photobiont, especially across the lichen’s geographic range. Thus, lichens are classified and defined by their mycobiont and are officially considered a type of fungus, despite their composite nature.
Trebouxia is the genus of green algae most commonly found in lichens. For many years, it was thought that Trebouxia could only rarely be found free-living in nature. However, a study by Mukhtar et al. (1994) found that free-living Trebouxia were among the first colonizers of rocks in an area following fire. Other recent studies also suggest that free-living Trebouxia exists in quantities high enough for lichen spores to form a new lichen if both land on a suitable substrate (Hinds, 2007). Trentepohlia, Coccomyxa, and Stichococcus are some other common genera of green algae that can become lichenized. Photobionts are not easy to identify beyond genus without isolating them from their mycobiont, and less than 5 percent of lichens have had their photobionts identified to species level (Brodo, 2001).
Cyanobacteria belong to an entirely different kingdom than the green algae. The most common genus is Nostoc, found mostly in jelly lichens (Collema and Leptogium), and in many species of Peltigera. All cyanobacterial photobionts can be found free-living in nature (Brodo, 2001).
Recent discoveries using molecular technologies and DNA analysis suggests lichens are better described as ecosystems rather than composite organisms. Hawksworth and Grube (2020) explain, “A lichen is a self-sustaining ecosystem formed by the interaction of an exhabitant fungus and an extracellular arrangement of one or more photosynthetic partners and an indeterminate number of other microscopic organisms.” Meaning, in addition to the photobiont and mycobiont, lichens also contain other fungi (mycobiome) and bacterial colonies (microbiome). And, as if that wasn’t complex enough, protists and viruses have also been known to associate with lichens.
Lichenization has evolved independently multiple times along different lineages in the fungal kingdom. Lichens do not all form a single clade where they are all related to one another; they are polyphyletic. Lichens are often described as a “life-style”, an evolved strategy of (simply put) farming photobionts as a means of obtaining food, just like other fungi form mycorrhizal relationships with the roots of living plants, or obtain nutrients from dead or decaying organic matter (saprophytes), or parasitic fungal pathogens (wilts, blights, and other necrotrophs).
LICHEN ECOLOGY AND CONSERVATION
Lichens contribute to critical ecosystem processes, including rock weathering, soil formation, nutrient cycling, and regulation of humidity regimes (Brodo, 2001). Lichens also provide a source of food, camouflage, and shelter for a number of organisms. Lichens, which are high in carbohydrates but low in protein, are eaten by mites, nematodes, slugs, springtails, bark lice, silverfish, caribou, mountain goats, reindeer, moose and pronghorns. Lichens are used as nesting material for mergansers, hawks, chickadees, thrushes, warblers, gnatcatchers, flycatchers, and hummingbirds. And they provide camouflage for species like the Northern Gray Treefrog and the Green Salamander. The green lacewing larva even adorns itself in lichens to help it blend into its surroundings (Brodo, 2001).
Despite their small size, high quantities of lichens can change the dynamics of entire forested ecosystems. Collectively, they can absorb significant amounts of nutrients from rainwater flowing down branches and tree bark. Also, by absorbing rainwater and releasing it slowly over time, lichens can regulate humidity levels throughout the forest. Lichens with cyanobacteria can also fix nitrogen, which can contribute to nutrient cycling in a forested setting. Some studies suggest that lichens can even contribute up to 50% of the nitrogen input to a forest, but this number requires further studies and likely varies by region and forest type (Brodo, 2001).
Lichens are vulnerable to a variety of pollutants, especially sulphur-dioxide, but also fluorides, ozone, hydrocarbons, and metals such as copper, lead, and zinc (Brodo, 2001). Some species of lichen are more sensitive to pollutants than others. Simply finding a lichen growing somewhere does not necessarily mean the air quality is good unless you identify the lichen and know it’s a species that is sensitive to air pollution. Pollution-sensitive lichens include those with high surface area like members of Usnea, Ramalina, and Teloschistes, and cyanolichens like Lobaria, Nephroma, Collema, and Leptogium (Brodo, 2001).
The primary threat to lichens over the past few centuries, however, has been habitat loss and destruction. Widespread deforestation of eastern North America during the 16th and 17th centuries has resulted in severe declines for many species of lichens. As secondary forests begin to recover and air quality improves, lichens are slowly recolonizing areas where they were once widespread. However, rare and sensitive species are still largely absent from highly disturbed landscapes, and lichen recolonization tends to be restricted to higher abundances of a small number of pollution-tolerant or generalist species (Allen et al., 2019).
Use of rare, sensitive, or specialist lichen species can be important for identifying habitats of conservation priority. For example, old-growth or mature forests have been shown to host significantly higher diversity of lichens, including more rare species, compared to younger and more disturbed forests. Calicioid lichens and fungi, often called pins or stubbles, are especially sensitive to habitat loss or degradation. Most pin lichens require old-growth or virgin forests with a high diversity of microhabitats (Allen et al., 2019).
New Jersey has no official list of rare or endangered lichen species. While a lichen checklist has been published by Waters and Lendemer (2019), there is insufficient data to assign informed rarity rankings for many of New Jersey’s approximately 500 lichen species. Some species, however, are undoubtedly rare and likely extirpated from the state. A few “holy-grail” species whose rediscovery in New Jersey would be extremely important to lichen conservation include: Lobaria pulmonaria, Lecanora willeyi, Anzia colpodes, and Usnea angulata.
Despite their small size, high quantities of lichens can change the dynamics of entire forested ecosystems. Collectively, they can absorb significant amounts of nutrients from rainwater flowing down branches and tree bark. Also, by absorbing rainwater and releasing it slowly over time, lichens can regulate humidity levels throughout the forest. Lichens with cyanobacteria can also fix nitrogen, which can contribute to nutrient cycling in a forested setting. Some studies suggest that lichens can even contribute up to 50% of the nitrogen input to a forest, but this number requires further studies and likely varies by region and forest type (Brodo, 2001).
Lichens are vulnerable to a variety of pollutants, especially sulphur-dioxide, but also fluorides, ozone, hydrocarbons, and metals such as copper, lead, and zinc (Brodo, 2001). Some species of lichen are more sensitive to pollutants than others. Simply finding a lichen growing somewhere does not necessarily mean the air quality is good unless you identify the lichen and know it’s a species that is sensitive to air pollution. Pollution-sensitive lichens include those with high surface area like members of Usnea, Ramalina, and Teloschistes, and cyanolichens like Lobaria, Nephroma, Collema, and Leptogium (Brodo, 2001).
The primary threat to lichens over the past few centuries, however, has been habitat loss and destruction. Widespread deforestation of eastern North America during the 16th and 17th centuries has resulted in severe declines for many species of lichens. As secondary forests begin to recover and air quality improves, lichens are slowly recolonizing areas where they were once widespread. However, rare and sensitive species are still largely absent from highly disturbed landscapes, and lichen recolonization tends to be restricted to higher abundances of a small number of pollution-tolerant or generalist species (Allen et al., 2019).
Use of rare, sensitive, or specialist lichen species can be important for identifying habitats of conservation priority. For example, old-growth or mature forests have been shown to host significantly higher diversity of lichens, including more rare species, compared to younger and more disturbed forests. Calicioid lichens and fungi, often called pins or stubbles, are especially sensitive to habitat loss or degradation. Most pin lichens require old-growth or virgin forests with a high diversity of microhabitats (Allen et al., 2019).
New Jersey has no official list of rare or endangered lichen species. While a lichen checklist has been published by Waters and Lendemer (2019), there is insufficient data to assign informed rarity rankings for many of New Jersey’s approximately 500 lichen species. Some species, however, are undoubtedly rare and likely extirpated from the state. A few “holy-grail” species whose rediscovery in New Jersey would be extremely important to lichen conservation include: Lobaria pulmonaria, Lecanora willeyi, Anzia colpodes, and Usnea angulata.
MORPHOLOGY
|
Foliose- The “leaf-like” form has a flattened thallus with a different color on the top and bottom. They commonly occur on tree trunks and one can (but shouldn’t!) peel them off with a knife. Foliose lichens often have structures called “rhizines” that secure the lichen to the substrate. These structures look like roots, but do not transport water or nutrients like the roots of a plant, and rarely penetrate deep into the substrate. Common examples of foliose lichens include Parmotrema hypotropum, Flavoparmelia caperata, and Physcia milligrana.
|
Foliose: Peltigera polyactylon
|
Foliose: Parmotrema perforatum
|
|
Crustose- Crustose lichens look like old chewing gum stuck to rocks and trees. Unlike foliose lichens, crustose lichens cannot be easily peeled off its substrate with a knife. In fact, lichenologists often have to use a rock hammer to collect crustose specimens. A subset of crustose lichens are referred to as “leprose”. Examples of common crustose lichens include Porpidia albocaerulescens, Graphis scripta, and Lecanora hybocarpa.
|
Crustose: Graphis scripta
|
Crustose: Lecanora subpallens
|
|
Squamulose- An intermediate growth form between crustose and foliose is known as “squamulose”, a growth form most common in the genus Cladonia. The lichen body is composed of tiny scales called squamules at the base which appear foliose, but are usually very small. The reproductive structure sticks up and is usually the most recognizable feature (appearing fruticose). British Soldier lichens (Cladonia cristatella) is squamulose.
|
Squamulose: Cladonia cf. chlorophaea
|
Squamulose: Cladonia cristatella
|
|
Fruticose- Fruticose lichens are those that grow either erect or that are pendent. Unlike foliose lichens, fruticose lichens are the same color around the entire lichen, without a clear upper and lower surface. Common fruticose lichens include Cladonia subtenuis, Usnea strigosus, and Pycnothelia papillaria.
|
Fruticose: Cladonia rangiferina
|
Fruticose: Usnea hirta
|
|
Leprose- Closely related to crustose lichens are another odd-ball growth form called leprose lichens. These lichens resemble powder, and are not as organized or aggregated as your typical, neatly circular crustose lichens. The genus Lepraria has several leprose lichens.
|
Leprose: Lepraria cf. finkii
|
SUBSTRATE
Lichens can grow on a variety of substrates. Some species are restricted to a single substrate type, others can grow on a variety of substrates.
Saxicolous (on rock)- Lichens can prefer either calcareous (limestone, dolomite, concrete, mortar) or noncalcarous (sandstone, granite, shale, etc.). rocksamoun. Rocks with especially high concentrations of metals like iron and magnesium can have their own lichen flora (Brodo, 48). Sandstones often have the ability to retain moisture for long periods of time, and their chemistry can vary depending on the material binding the rock particles together (Brodo, 48). Common examples of saxicolous lichens include Porpidia albocaerulescens, Umbilicaria mammulata, and Dimelaena oreina.
Terricolous (on soil)- Like rock, soil can be either calcareous or siliceous, depending on the chemistry of its parent material. Soil lichens produce bundles of hyphae that grow among the soil particles, binding them together (Brodo, 2001). Common examples include Dibaeis baeomyces, Placynthiella uliginosa, Pycnothelia papillaria, and many species of Cladonia, including Cladonia subtenuis, Cladonia uncialis, and Cladonia grayi.
Corticolous (on living wood, bark)- Different properties of bark can encourage or preclude different lichen species, including texture, moisture holding capacity, and chemistry. Some lichens are restricted to conifers, others hardwoods, and some can grow on both. Conifer bark tends to be acidic, contain organic resins and gums, and has lower levels of inorganic nutrients. Conifers also have dense canopies casting shade throughout the year, while hardwoods lose their leaves for 6 months out of the year, increasing sunlight and decreasing moisture (Brodo, 2001). Interestingly, two tree species tend to buck the trend. Birches (Betula spp.) are hardwoods that can often support lichens typically restricted to conifers. Likewise, Northern White Cedar (Thuja occidentalis), a rare tree in the wilds of New Jersey but commonly planted ornamentally, can support lichens more typically found on hardwoods (Brodo, 2001). Common corticolous lichens include Flavoparmelia caperata, Parmotrema hypotropum, Phaeophyscia rubropulchra, and Pyrrhospora varians.
Lignicolous (on decaying wood)- Rate or degree of decay is another important property that lichens seem to pay attention to. Like corticolous lichens, some lichens prefer decaying conifers, others decaying hardwoods. Common species include Multiclavula mucida, Cladonia ochrochlora, Cladonia incrassata, and Cladonia ramulosa.
Muscicolous (on bryophytes)- Bryophytes also grow on a substrate like rock, bark, or soil, so it can be difficult to determine affinity or presence of lichen on a bryophyte species. Not many lichens are solely muscicolous in New Jersey (if any). Common lichen species found growing on bryophytes include Lepraria finkii, and Cladonia grayi.
Lichenicolous (on lichens)- Some lichens grow on other lichens. They are often difficult to see in the field and are only discovered once collections are put under a microscope. They can be quite specialized on a small number of host lichens. Examples from New Jersey (common or otherwise) include Ovicuculispora parmeliae (on Punctelia rudecta, Physcia millegrana, and Parmelia sulcata), Clypecoccum hypocenomycis (on Hypocenomyce scalaris), and Endococcus propinquus (on Porpidia albocaerulescens).
Zooicolous (on animals)- The larvae of green lacewings (Leucochrysa pavida) can commonly be found in New Jersey using leprose lichens as camouflage. Some lichens can also be found on bones and antlers. In the Galapagos, lichens can grow on the shells of giant tortoises (Brodo, 2001).
Saxicolous (on rock)- Lichens can prefer either calcareous (limestone, dolomite, concrete, mortar) or noncalcarous (sandstone, granite, shale, etc.). rocksamoun. Rocks with especially high concentrations of metals like iron and magnesium can have their own lichen flora (Brodo, 48). Sandstones often have the ability to retain moisture for long periods of time, and their chemistry can vary depending on the material binding the rock particles together (Brodo, 48). Common examples of saxicolous lichens include Porpidia albocaerulescens, Umbilicaria mammulata, and Dimelaena oreina.
Terricolous (on soil)- Like rock, soil can be either calcareous or siliceous, depending on the chemistry of its parent material. Soil lichens produce bundles of hyphae that grow among the soil particles, binding them together (Brodo, 2001). Common examples include Dibaeis baeomyces, Placynthiella uliginosa, Pycnothelia papillaria, and many species of Cladonia, including Cladonia subtenuis, Cladonia uncialis, and Cladonia grayi.
Corticolous (on living wood, bark)- Different properties of bark can encourage or preclude different lichen species, including texture, moisture holding capacity, and chemistry. Some lichens are restricted to conifers, others hardwoods, and some can grow on both. Conifer bark tends to be acidic, contain organic resins and gums, and has lower levels of inorganic nutrients. Conifers also have dense canopies casting shade throughout the year, while hardwoods lose their leaves for 6 months out of the year, increasing sunlight and decreasing moisture (Brodo, 2001). Interestingly, two tree species tend to buck the trend. Birches (Betula spp.) are hardwoods that can often support lichens typically restricted to conifers. Likewise, Northern White Cedar (Thuja occidentalis), a rare tree in the wilds of New Jersey but commonly planted ornamentally, can support lichens more typically found on hardwoods (Brodo, 2001). Common corticolous lichens include Flavoparmelia caperata, Parmotrema hypotropum, Phaeophyscia rubropulchra, and Pyrrhospora varians.
Lignicolous (on decaying wood)- Rate or degree of decay is another important property that lichens seem to pay attention to. Like corticolous lichens, some lichens prefer decaying conifers, others decaying hardwoods. Common species include Multiclavula mucida, Cladonia ochrochlora, Cladonia incrassata, and Cladonia ramulosa.
Muscicolous (on bryophytes)- Bryophytes also grow on a substrate like rock, bark, or soil, so it can be difficult to determine affinity or presence of lichen on a bryophyte species. Not many lichens are solely muscicolous in New Jersey (if any). Common lichen species found growing on bryophytes include Lepraria finkii, and Cladonia grayi.
Lichenicolous (on lichens)- Some lichens grow on other lichens. They are often difficult to see in the field and are only discovered once collections are put under a microscope. They can be quite specialized on a small number of host lichens. Examples from New Jersey (common or otherwise) include Ovicuculispora parmeliae (on Punctelia rudecta, Physcia millegrana, and Parmelia sulcata), Clypecoccum hypocenomycis (on Hypocenomyce scalaris), and Endococcus propinquus (on Porpidia albocaerulescens).
Zooicolous (on animals)- The larvae of green lacewings (Leucochrysa pavida) can commonly be found in New Jersey using leprose lichens as camouflage. Some lichens can also be found on bones and antlers. In the Galapagos, lichens can grow on the shells of giant tortoises (Brodo, 2001).
IDENTIFICATION AND COLLECTION
Unlike with mushrooms, collecting lichens can negatively impact population health. One should always collect specimens on fallen branches before picking a lichen off a live branch. Before collecting any lichen, search the area to see if there are other specimens of the same species nearby. If you only see a single individual in the area, do not collect it. Instead, take photographs, record the location, and take notes on the substrate and associated species.
Scientific collection permits are needed before collecting any specimens (lichens or otherwise) on state-owned lands. You should always get permission from the property owner or preserve manager before collecting lichens.
Only collect if you are certain you’ll be able to deposit into an herbarium. If you properly collect a lichen from the wild, be sure to make a proper record by recording pertinent information (GPS coordinates, substrate, date, etc.), and keep specimens organized so they can be eventually submitted to an herbarium. Record pertinent identification features like measurements, color, chemical reactions, or presence/absence of structures. Photos can also be helpful, since specimens dry over time and can lose their color and form. Herbarium collections are especially important for rare species and species thought to be state or county records (i.e., there are no other known collections from that area).
Identification of lichens often requires the use of a microscope (a dissecting or stereomicroscope and/or a compound microscope). Dissecting probes, fine tweezers, and a razor blade are useful. Several chemical tests are often needed, including KOH (often abbreviated as K), NaOCl (Sodium hypochlorite, often abbreviated as C), and para-phenylenediamine (often abbreviated PD). Household lye (sodium hydroxide, NaOH) can be substituted for KOH, and commercial laundry bleach can be used in place of lab-grade NaOCl. However, PD must be ordered from a chemical supply store, and is often only available in large amounts (and is quite toxic!).
Illustrated glossaries and lichen term definitions can be readily found online (a few are listed in the below section on Recommended Websites).
Scientific collection permits are needed before collecting any specimens (lichens or otherwise) on state-owned lands. You should always get permission from the property owner or preserve manager before collecting lichens.
Only collect if you are certain you’ll be able to deposit into an herbarium. If you properly collect a lichen from the wild, be sure to make a proper record by recording pertinent information (GPS coordinates, substrate, date, etc.), and keep specimens organized so they can be eventually submitted to an herbarium. Record pertinent identification features like measurements, color, chemical reactions, or presence/absence of structures. Photos can also be helpful, since specimens dry over time and can lose their color and form. Herbarium collections are especially important for rare species and species thought to be state or county records (i.e., there are no other known collections from that area).
Identification of lichens often requires the use of a microscope (a dissecting or stereomicroscope and/or a compound microscope). Dissecting probes, fine tweezers, and a razor blade are useful. Several chemical tests are often needed, including KOH (often abbreviated as K), NaOCl (Sodium hypochlorite, often abbreviated as C), and para-phenylenediamine (often abbreviated PD). Household lye (sodium hydroxide, NaOH) can be substituted for KOH, and commercial laundry bleach can be used in place of lab-grade NaOCl. However, PD must be ordered from a chemical supply store, and is often only available in large amounts (and is quite toxic!).
Illustrated glossaries and lichen term definitions can be readily found online (a few are listed in the below section on Recommended Websites).
RECOMMENDED RESOURCES
Websites
|
Books
|
|
Journal Articles
- Allen, J.L., McMullin, R.T., Tripp, E.A., & Lendemer, J.C. (2019). Lichen conservation in North America: a review of current practices and research in Canada and the United States. Biodiversity and Conservation, 28, 3103-3138.
- Hawksworth, D. L., Grube, M. (2020). Lichens redefined as complex ecosystems. New Phytologist, 227, 1281-1283.
- Lendemer, J. C. (2006). Contributions to the Lichen Flora of New Jersey: A Preliminary Checklist of the Lichens of Wharton State Forest. Opuscula Philolichenum, 3, 21–40.
- Mark, K., Laanisto, L., Bueno, C. G., Niinemets, Ü., Keller, C., & Scheidegger, C. (2020). Contrasting co‐occurrence patterns of photobiont and cystobasidiomycete yeast associated with common epiphytic lichen species. New Phytologist, 227(5), 1362–1375.
- Mukhtar, A., Garty, J., & Galun, M. (1994). Does the Lichen Alga Trebouxia Occur Free-Living in Nature: Further Immunological Evidence. Symbiosis, 17, 247–253.
- Ray, D.G., Barton, J.W., & Lendemer, J.C. (2015). Lichen community response to prescribed burning and thinning in southern pine forests of the mid-Atlantic coastal plain, USA. Fire Ecology, 11(3), 14-33.
- Tripp, E.A., & Lendemer, J.C. (2017). Twenty-seven modes of reproduction in the obligate lichen symbiosis. Brittonia, 70(1), 1-14.
- Waters, D. P., & Lendemer, J. C. (2019a). A revised checklist of the lichenized, lichenicolous and allied fungi of New Jersey. Bartonia, 70, 1–62.
- Waters, D. P., & Lendemer, J. C. (2019b). The Lichens and Allied Fungi of Mercer County, New Jersey. Opuscula Philolichenum, 18, 17–51.
YouTube
- “Lichen Identification Workshop for Beginners” by Rebecca Yahr, Royal Botanic Garden Edinburgh & British Bryological Society
- “Long Island lichens: an exploration of a hidden world” by Dr. James Lendemer, Institute of Systemic Botany, The New York Botanical Garden
- “Science @ Sugarlands: Lichens of the Smokies, Revealed” by Dr. James Lendemer, Institute of Systemic Botany, The New York Botanical Garden
- “Lunchtime Discovery: Lichens of North Carolina” by Garl Perlmutter, North Carolina Department of Environmental Quality
Last Updated: 2022-08-31
