Crustose lichens associated with dead wood in northwestern North America: a review

Review Draft, 25 March 2005

Toby Spribille1, Curtis Björk2 and Trevor Goward2

Abstract. Substrate affinities were reviewed for 506 species of epiphytic crustose lichens in northwestern North America based on literature and recent field research. A total of 241 species have been recorded as growing on wood, of which 50, or 10% of all epiphytic crustose lichens, have been found only on this substrate. The list of apparently obligate lignicoles includes both well-known species frequently encountered on wood as well as several that have been only recently reported or are as yet undescribed. More work is needed to determine the occurrence, richness and ecological amplitudes of lignicolous species in the various forest ecosystems of northwest North America.

Introduction

The role of dead wood in forested ecosystems has been the topic of increasing discussion and research in recent years. This interest in dead wood has been propelled by several factors: 1) the observation that levels of dead wood in many forested ecosystems have fallen precipitously from what they were historically (Linder & Ostlund 1998); 2) recognition of the importance of dead wood for various plants and animals; and 3) forestry-driven (and in part, regulation-mandated) research to identify minimum levels of dead wood for the maintenance of nutrient cycling function and viability of dead-wood-dependent species.

In natural forests, dead wood occurs in a large variety of forms. Perhaps in its most unobvious manifestation, dead, decorticate lower branches of old living trees may provide the first habitat for lignicoles in a developing forest. Tree death and eventual loss of branches and bark creates a snag, with a more appreciable surface area for lignicole colonization. The fall of a snag may be sudden, creating a prostrate log on the forest floor, or the falling snag may become lodged in other trees, slowing its fall to the ground to a process of years. Logs in turn exhibit many characteristic stages of decay and weathering as the dead wood comes into contact with the ground and is buried under snow in winter. The relative amount and decomposition behaviour of dead wood is furthermore ecosystem- and climate-specific, with higher rates of rot in moist than in dry ecosystems (Brown et al. 1996).

The life histories of many species are closely linked to the various types of dead wood. In British Columbia, for instance, approximately one-third of all forest-dwelling bird and mammal species use snags as sites for foraging, roosting or nesting (Bunnell & Kremsater 1990). Both coarse and fine woody debris have also been demonstrated to be important for entire communities of less conspicuous organisms, such as saproxylic insects (Bouget & Duelli 2004) and wood-inhabiting fungi (Kruys & Jonsson 1999, Norden et al. 2004)

1 Department of Vegetation Analysis, University of Göttingen, 37073 Göttingen, Germany; [email protected] 2 Edgewood Blue, Box 131, Clearwater, BC V0E 1N0, Canada

1 The importance of dead wood for lichens has long been appreciated, particularly in Europe (e.g., Chlebicki et al. 1996, Lõhmus & Lõhmus 2001, Humphrey et al. 2002). Even in Europe, however, no systematic surveys have been made of the contribution of lignicolous lichens to overall biodiversity and it is difficult to estimate what percentage of the overall flora they constitute.

In northwest North America, there have been no published surveys focused specifically on lignicolous lichens, even at a local scale. Nevertheless, scores of floristic and taxonomic surveys from different parts of northwest North America over the past 25 years have provided a rich, until now untapped source of anecdotal evidence on substrate affinities for hundreds of lichen species. Here, we present the first systematic, literature-based survey of substrate affinities of a subset of the overall lichen flora of northwestern North America, namely the bark- and wood-dwelling crustose lichens.

Materials and Methods

We used a pre-existing database of 569 epiphytic crustose lichens of northwestern North America, defined here as including British Columbia, Washington, Oregon, California (north of 37 degrees), Idaho and Montana; individual lichen records from southeastern Alaska were also used in some instances. Our decision to use crustose lichens was based mainly on two practical considerations: 1) crustose lichens have been repeatedly identified as one of the main lichen groups displaying particular affinities for dead wood, both in northern Europe and in preliminary studies in British Columbia (Goward et al., in prep., Spribille, unpubl.); and 2) we were able to access a literature database developed for work on an upcoming crustose lichen flora of the same study area (Spribille & Goward, in prep.).

Our first step was to filter out taxonomic problems, synonyms and questionable records from our database. This provided us with a list of ‘accepted’ names (Appendix 1). Next, we checked every known recent literature reference for each species in the database for information on substrate. Substrates were recorded as follows: wood, bark, moss/plant detritus, leaves, or resin. In addition to available literature, we also took into consideration recent unpublished studies (Goward et al., in prep., Spribille, unpubl.) as well as verified herbarium specimens in the collections of the authors. A discriminating approach was used to ensure data quality: most of the literature used was published after 1980, and special emphasis was given to recent systematic and floristic treatments. A list of references used for the review is in Appendix 2. Finally, substrate affinities were summarized in a master table and analyzed with an emphasis on wood-dwelling crustose lichen species. For analysis, crustose lichens were divided into two categories: non-calicioid crusts, encompassing four fifths of the lichen flora and customarily referred to simply as crustose lichens; and calicioid crusts (sensu Goward 1999), i.e. those bearing stalked apothecia, including numerous non-lichenized species of the order Mycocaliciales traditionally studied by lichenologists (Tibell & Wedin 2000).

Results

Of the 569 species included in the initial database, substrate data could be found for 506 species (Table 1; Appendix 2). The remaining 63 species fell into four categories: records available but substrate not indicated (2 species), records based on unverified, unpublished

2 specimens not seen by us (12 species), species previously assumed to occur in the flora but for which no supporting evidence could be found (14 species) and species for which literature was not available at the time of this writing (35 species).

Of the 506 species for which data could be found, 241 have been recorded as occurring on wood and 434 on bark (Table 1). The ratios of species on bark vs. wood are quite different for non-calicioid and calicioid species groups: a similar number of calicioids occurs on wood (63 species) and bark (73 species), whereas among non-calicioid crusts, 363 species are found on bark, more than twice as many as the number found on wood (178 species; see Table 1).

Of particular interest are the species that occur only on a single substrate type. When all crustose lichens are taken together, fifty species, or 10% of all species for which we had data, were recorded only on wood (obligate lignicoles; Tables 2 and 3). A large number of species are found only on bark, with 206 non-calicioid crustose (51%) and 34 calicioid species (32%) apparently bound to certain bark substrates and not known to go over onto wood, moss or other substrates. A smaller relative percentage of non-calicioid crusts are found only on wood (28 species, or 7%) compared to calicioids (22 species, or 21%).

Discussion

The available data suggest that a significant proportion of crustose lichens occur on dead wood and a large portion of these are strictly limited to this substrate. In addition, of the numerous species that occur both on wood and bark, many occur primarily on wood and only rarely on bark and vice versa. More detailed constancy or frequency data would be useful to highlight this pattern in more detail, but such detail will remain unavailable without more extensive and systematic exploration of the epiphytic crust lichen flora of the region.

While it is true that the incompleteness of substrate data for some species may erroneously give the impression that some species are strict lignicoles or corticoles, most of the species included on the list have been collected multiple times and reported in more than one study. The increased level of collecting since the 1980s has permitted the sketching of ecological profiles for many species. Examples for such species include Lecanora orae- frigidae and Lecanora xylophila, two crust species found on driftwood, logs and fence rails in coastal areas (Brodo & Vänskä 1984). Calicioid lichens are another example of a group about which our knowledge has continuously grown in recent years. Many of the obligately lignicolous calicioids have been surveyed systematically in independent ecological studies in both Oregon by Rikkinen (2003a) and British Columbia (Goward et al., in prep.); ecological profiles for many species are thus becoming apparent. Furthermore, a review of literature from Europe, where many of the same lignicolous species also occur, reveals that, with few exceptions, species reported to be dead-wood obligates in the present review are also found primarily on this substrate across the Atlantic.

It is in fact quite likely that the numbers of obligate lignicoles will rise. It is worthy of note that calicioids, which are proportionately much better represented on wood than non- calicioid crusts, have also been surveyed in far more detail in recent years than non-calicioid crusts. In fact, nearly all of the obligately lignicolous calicioids were discovered since 1990. Moreover, of the obligate lignicoles, three of the non-calicioid and five of the calicioid species are new to science, and thus the products of the most recent taxonomic research. Our increasing knowledge of the flora may begin to point in the direction of another noteworthy

3 phenomenon, namely lignicole endemism in our flora. Based on the current assessment, the list of obligate lignicoles includes three apparently endemic crust species and three endemic calicioid species, one of which is a recently described, monotypic genus, Brucea, found only on the wood of beaver scars (Rikkinen 2003b).

The current data also allow speculation as to the niche specialization of lignicoles. Species that occur exclusively on standing snags and not on fallen logs, are known among both the non-calicioid and calicioid crusts (Tables 2 and 3). Several are specific to hard snags (e.g., Fuscidea sp. 1, Micarea excipulata, Mycocalicium spp.) while others are found only on soft, flaking bark of snags in which decay is in an advanced stage (e.g., Chaenothecopis viridireagens, Microcalicium ahlneri). Yet other species are found only on prostrate, decorticated logs (e.g., Buellia arborea, B. chloroleuca). At least two species are restricted to driftwood, one (Hafellia fosteri) on the immediate coast and another (Verrucaria sp. 1) on water-scoured logs in mountain streams. Such specific microhabitat relationships require detailed systematic study.

Conclusions

Much work remains to be done on documenting lignicolous lichens, not only in the study area but also in other parts of the world. Initial indications point to a significant number of species found only on dead wood. The maintenance of sufficient levels of dead wood will be decisive in preventing many lignicoles from sliding into extinction. The present survey is intended to attract attention to this problem and encourage more research. More data are needed to identify lignicole diversity patterns, ecological hotspots, and niche specialization. Recommendations for forest management will require a good overview of diversity patterns. Focused studies should be carried out in representative ecosystems and characteristic lignicoles identified for each ecosystem.

The review of a large set of literature permits a unique perspective on the prevailing methods and habits of reporting lichen records. Collectors and authors of floristic papers should not underestimate the significance of detailed information on species’ ecology. When documenting lignicolous occurrences, collectors should provide the degree of rot of the wood, position on trunk relative to ground, whether a snag is leaning, and the species of snag, if known, as well as whether the snag is in open or dense forest. Present evidence suggests that such levels of fine-scale habitat differentiation are indeed meaningful for lichen species and their recording would not represent an ‘overkill’ of habitat data.

Current data point to nearly half of all species occurring at least in part on dead wood, and no less than 10% of all epiphytic crustose species being exclusively restricted to this substrate. Further inventory and delimitation of ecological amplitudes is necessary to complete the picture of lignicolous lichen distribution patterns. Notwithstanding, it is apparent that dead wood is indispensable for the existence of about one in ten epiphytic crust species. Management strategies built not only around dead wood in a general sense but specifically tailored to the types of dead wood required by niche specialists (e.g. standing and leaning snags, different types and diameters of down logs) will be key if viable populations of wood- dependent species are going to be maintained into the future.

4 Acknowledgments

John Sheard (Saskatoon) and Tor Tønsberg (Bergen, Norway) are thanked for providing unpublished substrate data for numerous species. Viktoria Wagner (Göttingen) helped with preparing the database. This study was supported by Forest Science Program funding provided by the Department of Forest Sciences of the University of British Columbia.

Literature

Brodo, IM & Vänskä H (1984): Notes on the maritime, lignicolous lichen Lecanora orae- frigidae. Lichenologist 16: 45-51.

Brown S, Mo JM, McPherson JK, Bell, DT (1996): Decomposition of woody debris in western Australian forests. Canadian Journal of Forest Research 26 (6): 954-966.

Bunnell F, Kremsater LL (1990): Sustaining wildlife in managed forests. Northwest Environmental Journal 6: 243-269.

Chlebicki A, Zarnowiec J, Cieslinski S, Klama H, Bujakiewicz A, Zaluski T (1996) Epixylites, lignicolous fungi and their links with different kinds of wood. In: Falinski JB & Mulenko W (eds.): Cryptogamous Plants in the Forest Communities of Bialowieza National Park. Functional Groups Analysis and General Synthesis (Project CRYPTO 3). Phytocoenosis Vol. 8 (N.S.) Archivum Geobotanicum 6, Bialowieza Geobotanical Station, Warszawa - Bialowieza, pp. 75-110.

Goward, T (1999): The lichens of British Columbia. Part 2. Fruticose species. B.C. Ministry of Forests Research Program, Victoria, B.C.

Humphrey JW, Davey S, Peace AJ, Ferris R, Harding K (2002): Lichens and bryophyte communities of planted and semi-natural forests in Britain: the influence of site type, stand structure and deadwood. Biological Conservation 107: 165-180.

Kruys N & Jonsson BG (1999): Fine woody debris is important for species richness on logs in managed boreal spruce forests of northern Sweden. Canadian Journal of Forest Research 29: 1295-1299.

Linder P & Ostlund L (1998): Structural changes in three mid-boreal Swedish forest landscapes, 1885-1996. Biological Conservation 85: 9-19.

Lõhmus P & Lõhmus A (2001): Snags and their lichen flora in old Estonian peatland forests. Annales Botanici Fennici 38: 265-280.

Norden B, Ryberg M, Gotmark F, Olausson B (2004): Relative importance of coarse and fine woody debris for the diversity of wood-inhabiting fungi in temperate broadleaf forests. Biological Conservation 117 (1): 1-10.

Rikkinen J (2003a): Calicioid lichens and fungi in the forests and woodlands of Oregon. Acta Botanica Fennica 175: 1-41.

5 Rikkinen J (2003b): New resinicolous ascomycetes from beaver scars in western North America. Annales Botanici Fennici 40: 443-450.

Tibell L, Wedin M (2000): Mycocaliciales, a new order for nonlichenized calicioid fungi. Mycologia 92: 577-581.

6 Table 1. Numbers of crustose and calicioid species on bark and wood.

Crusts Calicioids Total Wood only 28 22 50 Wood and bark 142 39 181 Wood and other 8 2 10 substrates* Total wood 178 63 241 Bark only 206 34 240 Bark and other 15 0 15 substrates* Total bark 363 72 434 Leaves/needles only 2 0 2 Conifer resin only 0 7 7 Shelf fungi only 0 1 1 Total 401 105 506

*includes muscicolous, saxicolous, foliicolous or resinicolous species that have been recorded on bark or wood or that were included in the survey.

7 Table 2: Non-calicioid microlichens reported in the Pacific Northwest only from dead wood.

Oregon. Western Europe, western North Absconditella lignicola Vezda & Pišut On logs America Dry interior areas, Montana. Western Buellia arborea Coppins & Tønsberg On logs Europe, western North America Dry interior areas, BC and Montana. Buellia chloroleuca Körb. On hard fallen logs Western Europe, western North America Interior BC. Widespread, in Europe also Catillaria nigroclavata (Nyl.) Schuler On snags on bark Interior BC. Western Europe, western Catinaria neuschildii (Körber) P. James On hard snags North America Fuscidea sp. 1 On hard snags Interior BC. Undescribed species Hafellia fosteri Imsh. & Sheard On seashore driftwood Coastal areas. Western North America. Inland BC. Otherwise western Europe, Lecanora anopta (Nyl.) Mot. On snags Greenland. Lecanora hypopta (Ach.) Vain. On logs Widespread, probably circumboreal Dry inland. Perhaps interruptedly Lecanora mughicola Nyl. On wood circumboreal Coastal areas. Western Europe, western Lecanora orae-frigidae R. Sant. Driftwood, logs, fence rails North America Lecanora xylophila Hue On seashore driftwood. Coastal areas. East and west coast of NA Lecidea myriocarpella (G.K. Merr.) Zahlbr. On wood Washington. Western North America. Lecidea plebeja Nyl. On wood Widespread, in Europe also on bark Washington; known only from type “Lecidea” pullula (Tuck.) Zahlbr. On wood. collection. On stumps and conifer Coastal areas. Western Europe / Micarea alabastrites (Nyl.) Coppins snags. Macaronesia, western North America. Micarea erratica (Körber) Hertel, Rambold On wood Washington & Pietschmann Dry inland areas; Western Europe, western Micarea excipulata Coppins On hard snags North America British Columbia, Washington; widespread Micarea melaena (Nyl.) Hedl. On soft snags on other substrates in Europe Ophioparma “fecunda” Bjork, ined. On snags Undescribed species, Idaho Ptychographa xylographoides Nyl. On decorticate wood. Western Europe, western North America Verrucaria sp. 1 On driftwood. Undescribed species, Montana On decorticate stems of Xerotrema megalospora Sherw. & Coppins Known only from Oregon, Scotland Arctostaphylos Xylographa hians Tuck. On logs and snags Western North America. Xylographa opegraphella Nyl. ex Rothr. On fallen logs North America only? Xylographa parallela (Ach.) Behlen & On hard snags, fallen logs Widespread, circumboreal Desberg Coastal. Western Europe, western North Xylographa trunciseda (Th. Fr.) Minks On decaying wood America Xylographa vitiligo (Ach.) Laundon On hard snags, fallen logs Widespread, circumboreal

8 Table 3: Calicioid microlichens reported in the Pacific Northwest only from dead wood.

Brucea castoris Rikkinen On beaver scars Known only from Oregon Calicium trabinellum Ach. On snags Dry inland areas, BC, Montana Chaenotheca nitidula Tibell On soft snags Recently described species Chaenotheca xyloxena Nádv. On wood. Widespread, California to Montana, BC Chaenothecopsis "hypocenomyceae" On conifer wood British Columbia Chaenothecopsis "rufescens" On birch wood British Columbia Chaenothecopsis "sphaerica" On wood British Columbia, Idaho Chaenothecopsis "viridipusilla" On wood British Columbia Chaenothecopsis debilis (Sm.) Tibell On wood California to Yukon Resin and wood of Chaenothecopsis nigripunctata Rikkinen Oregon, Washington, perhaps endemic Tsuga Chaenothecopsis parasitaster (Bagl. & Car.) D. On conifer snag Oregon, Washington Hawksw. Chaenothecopsis pusilla (Ach.) A.F.W. Schmidt On conifer wood California to Alaska Chaenothecopsis pusiola (Ach.) Vainio On conifer wood Oregon to BC Chaenothecopsis savonica (Räsänen) Tibell On conifer wood California to BC Chaenothecopsis sp. 1 (sensu Rikkinen) On hard wood California, Oregon; undescribed species Chaenothecopsis viridireagens (Nádv.) A.F.W. On soft snags Humid inland regions Schmidt Cyphelium notarisii (Tul.) Blomb. & Forss. On wood Montana east of Continental Divide Microcalicium ahlneri Tibell On soft snags Humid inland regions Microcalicium conversum Tibell Wood of Quercus Northern California Mycocalicium albonigrum (Nyl.) Fink On hard wood Oregon, Washington Mycocalicium subtile (Pers.) Szat. On hard snags Inland, from low to high elevations. Mycocalicium cf. victoriae (C. Knight ex F. On wood Oregon Wilson) Tibell Thelomma occidentale (Herre) Tibell On wood, esp fences California to BC

9 Appendix 1: species database with substrates (see attachment, crusts by substrate 25 mar 2005.xls)

Appendix 2: papers included in literature review.

Ahti, T., G.W. Scotter & H. Vänskä 1973. Lichens of the Reindeer Preserve, Northwest Territories, Canada. Bryologist 76: 48-76. Ahti, T., I. M. Brodo, & W. J. Noble. 1987. Contributions to the lichen flora of British Columbia, Canada. Mycotaxon 28: 91-97. Alstrup, V. & M. S. Cole. 1998. Lichenicolous fungi of British Columbia. The Bryologist 10: 221-229. Aptroot, A. 1996. New records of lichens and lichenicolous fungi from British Columbia. The Bryologist 99(2): 196-198. Arup, U. 1997. Correction of reports of two Caloplaca species from North America. Bryologist 100: 516. Bird, C.D., Thomson, J.W., Marsh, A.H., Scotter, G.W., Wong, P.Y. 1981. Lichens from the area drained by the Peel and Mackenzie Rivers, Yukon and Northwest Territories, Canada. II. Microlichens. Canadian Journal of Botany 59: 1231-1252. Breuss, O. 2000. Topeliopsis toensbergii (Lichens, Thelotremataceae) new to Canada. Evansia 17(3): 90. Brodo, I.M. 1984. The North American species of the Lecanora subfusca group. Beihefte zur Nova Hedwigia 79: 63-185. Brodo, I.M. & A. Henssen. 1995. A new isidiate crustose lichen in northwestern North America. Bibl. Lichenol. 58: 27-41. Brodo, I.M. & H. Vänskä 1984. Notes on the maritime, lignicolous lichen Lecanora orae-frigidae. Lichenologist 16: 45-51. Brodo, I.M. & O. Vitikainen. 1984. The typification of Lecanora subfusca (L.) Ach., its varieties, and some of its related taxa published before 1850. Mycotaxon 21:281-298. Brodo, I.M. & T. Tonsberg. 1994. A new species of Micarea with stalked pycnidia from the west coast of North America. Acta Botanica Fennica 150: 1-4. Brodo, I.M. & V. Wirth 1998. Lichens and lichenicolous fungi of the Queen Charlotte Islands, British Columbia, Canada. 4. The genus Fuscidea (Fuscideaceae). Pp. 149-162 in M. G. Glenn, R. C. Harris, R. Dirig, and M. S. Cole, (eds.) Lichenographia Thomsoniana: North American Lichenology in Honor of John W. Thomson. Mycotaxon Ltd., Ithaca, New York. Brodo, I.M. 1991. Studies in the lichen genus Ochrolechia. 2. Corticolous species of North America. Can. J. Bot. 69(4): 733-772. Brodo, I.M. 1995. Lichens and lichenicolous fungi of the Queen Charlotte Islands, British Columbia, Canada. 1. Introduction and new records for B.C., Canada and North America. Mycotaxon 56: 135-173. Brodo, I.M., Sharnoff, S. & Sharnoff, S. 2001. Lichens of North America. Yale University Press. Brodo, I.M., W. J. Noble, T. Ahti, and S. Clayden. 1987. Lichens new to North America from the flora of British Columbia, Canada. Mycotaxon 28: 99-110. Coleman, B.B., W. C. Muenscher & D. R. Charles. 1956. A distributional study of the epiphytic plants of the Olympic Peninsula, Washington. Amer. Midl. Nat. 56: 54-87. Cooke, W. B. 1955. Fungi, lichens and mosses in relation to vascular plant communities in eastern Washington and Idaho. Ecol. Monogr. 25: 119-180. Coppins, B. J. & Tønsberg, T. 2001. A new xanthone-containing Micarea from northwest Europe and the Pacific Northwest of North America. Lichenologist 33: 93-96. Coppins, B.J. 1983. A taxonomic study of the lichen genus Micarea in Europe. Bulletin of the British Museum (Natural History), Botany Series, 11: 17-214. Coppins; B.J. & T. Spribille 2004. Micarea subalpina Coppins & Spribille, a new subalpine species from the Rocky Mountains, U.S.A. Lichenologist 36(2): 97-102. DeBolt, A. & B. McCune. 1993. Lichens of Glacier National Park, Montana. Bry. 96: 192-204. Derr, C. C., R. D. Lesher & M. Boyle. 1996. Draft Management Recommendations for [separate reports, with authority names after the species names]. Dibben, M. J. 1980. The Chemosystematics of the Lichen Genus Pertusaria in North America North of Mexico. Publications in Biology and Geology No. 5, Milwaukee Public Museum, Milwaukee. 162 pages. Douglas, G.W. 1974. Lichens of the North Cascades Range, Washington. The Bryologist 77: 582-592. Egan, R. S. 1987. A fifth checklist of the lichen-forming, lichenicolous and allied fungi of the continental United States and Canada. The Bryologist 90(2): 77-173. Egea, J. M. & P. Torrente 1993. Cresponea, a new genus of lichenized fungi in the order Arthoniales (Ascomycotina). Mycotaxon 48: 301-331. Ekman, S. & Tønsberg, T. 1996. A new species of Megalaria from the North American west coast, and notes on the generic circumscription. Bryologist 99: 34-40.

10 Ekman, S. 1996. The corticolous and lignicolous species of Bacidia and Bacidina in North America. Opera Botanica 127: 1-148. Esslinger, T.L. 1997-onwards. A cumulative checklist for the lichen-forming, lichenicolous and allied fungi of the continental United States and Canada {Online}. North Dakota State University, Fargo, North Dakota. Available online at: http://www.ndsu.nodak.edu/instruct/esslinge/chcklst/chcklst7.htm Etayo, J. & O. Breuss 1998. New species and interesting records of lichenicolous fungi. Österreichische Zeitschrift für Pilzkunde 7 : 203-213. Eversman, S. 1979. Preliminary distributional study of the epiphytic macrolichens of Montana. Proc. Montana Acad. Sci. 38:60-62. Eversman, S. 1982. Epiphytic lichens of a Ponderosa pine forest in southeastern Montana. Bry. 85:204-213. Eversman, S. 1990. Lichens of Yellowstone National Park. Bry. 93:197-205. Eversman, S. 1995. Lichens of alpine meadows on the Beartooth Plateau, Montana and Wyoming, USA. Arctic and Alpine Research 27:400-406. Eversman, S. 1998. Lichens of Grand Teton National Park, Wyoming. Pp. 295-308 in M. G. Glenn, R. C. Harris, R. Dirig, and M. S. Cole, editors, Lichenographia Thomsoniana: North American Lichenology in Honor of John W. Thomson. Mycotaxon Ltd., Ithaca, New York. Eversman, S. 1999. Lichens of Yellowstone National Park Phase II. Unpublished report to U.S.G.S. Biological Resources Division. 62 pp. Eversman, S., Wetmore, C.M., Glew, K., Bennett, J.P. 2002. Patterns of lichen diversity in Yellowstone National Park. The Bryologist 105(1): 27-42. Eyerdam, W.J. 1949. Lichens from Alaska: Thum Bay, Knight Island, Prince William Sound. The Bryologist 52(1): 34-38. Eyerdam, W.J. 1960. Lichens new to the state of Washington. The Bryologist 63(2): 107-110. Fink, B. 1919. Additions to lichen distribution in North America. Mycologia 11:296-307. Fink, B. 1935. The lichen flora of the United States. Ann Arbor. Foster, A.S. 1908. Alnus oregana as cryptogamic host. The Bryologist 11: 33-35. Funk, A. 1973. Microlychnus gen. nov., a lichenized hyphomycete from western conifers. Canadian Journal of Botany 51: 1249-1250. Funk, A. 1980. A description of Verrucaria plumbaria on Douglas-fir. Mycologia 72: 422-425. Funk, A. 1983. Szczawinskia, a new genus of the lichen-forming Coleomycetes. Syesis 16: 85-88. Goward, T., Diederich, P., Rosentreter, R. 1994. Notes on the lichens and allied fungi of British Columbia. II. Bryologist 97: 56-62 Goward, T., McCune, B. & Meidinger, D. 1994. The lichens of British Columbia, Illustrated keys. Part 1 - Foliose and squamulose species. British Columbia, Ministry of Forests, Special Report Series no. 8, i-iii, 1- 181. Goward, T., O. Breuss, B. Ryan, B. McCune, H. Sipman, & C. Scheidegger. 1996. Notes on the lichens and allied fungi of British Columbia. III. Bryologist 99:439-449. Goward, T., Thor, G. 1992. Notes on the lichens and allied fungi of British Columbia. I. The Bryologist 95(1): 33-37. Hafellner, J. 1989. Die europäischen Mycobilimbia-Arten - eine erste Übersicht (lichenisierte Ascomycetes, Lecanorales). Herzogia 8: 53-59. Hafellner, J. 1993. Die Gattung Pyrrhospora in Europa. Eine erste Übersicht mit einem Bestimmungsschlüssel der Arten nebst Bemerkungen zu einigen aussereuropäischen Taxa (lichinisierte Ascomycotina, Lecanorales). Herzogia 9: 725-747. Hafellner, J. 1994. On Biatoridium, a resurrected genus of lichenized fungi (Ascomycotina, Lecanorales). Acta Bot. Fennica 150:39-46. Hafellner, J. 1997. A world monograph of Brigantiaea (lichenized Ascomycotina, Lecanorales). Symb. Bot. Ups. 32(1):35-74.. Harris, R.C. 1973. Corticolous pyrenolichens of the Great Lakes region. Michigan Botanist 12: 3-68. Harris, R.C. 1975. A taxonomic revision of the genus Arthopyrenia Massal. s. lat. (Ascomycetes) in North America. Ph.D. Diss., Michigan State University. 288 pages. Harris, W.P. & C.W. Harris. 1904. Lichens and mosses of Montana. Bull. Univ. of Mont. 19:311-330. Hasse, H.E. 1913. The lichen flora of southern California. Contributions from the United States National Herbarium/Contrib. U.S. Natil. Herb. 17: 1-132. Hauck, M. & T. Spribille 2002. The Mn/Ca and Mn/Mg ratios in bark as possible cause for the occurrence of Lobarion lichens on conifers in the dripzone of Populus in western North America. Lichenologist 34(6): 527- 532. Hedrick, J. 1942. Lichens in and near the Olympic National Park, Washington. Papers Mich. Acad. Sci. 27: 45- 56. Herre, A.W.C.T. 1917. Preliminary notes on the lichens of Whatcom County, Washington. The Bryologist 20: 76-84.

11 Herre, A.W.C.T. 1943 Two new species of lichens and new records for Washington state and North Carolina. Proc. Biol. Soc. Wash. 56: 17-20. Howard, G. E. 1937. Preliminary report of the lichens of the State of Washington. The Bryologist 40: 91-112. Howard, G. E. 1950. Lichens of the State of Washington. Univ. Washington Press, Seattle. Howard, G. E. 1955. Lichens of northwest America collected by W. N. Suksdorf. The Bryologist 58: 49-64. Howard, G. E. 1970. The lichen genus Ochrolechia in North America north of Mexico. The Bryologist 73:93-130. Imshaug H.A. & I. M. Brodo 1966. Biosystematic studies on Lecanora pallida and some related lichens in the Americas. Nova Hedwigia 12: 1-59. Imshaug H.A. 1951 (1952). The lichen-forming species of the genus Buellia occurring in the United States and Canada. University Microfilms, Ann Arbor. Jones, M. E. 1901. Montana botany notes containing descriptions of new species, lists of plants not heretofore recorded from the state, and notes on disputed species. Univ. Mont. Bull. 61 [Biol. Ser. No. 15]: 1-75. Jonescu, M. E. 1970. Lichens on Populus tremuloides in west-central Canada. Bry. 73:557-578. Jørgensen, P. M. & T. Tønsberg. 1999. Notes on some small species of Leptogium from Pacific North America. Bryol. 102: 412-417. Kalb, K. and B. Staiger 1995. Rindenbewohnende Arten der Flechtengattung Ophioparma in Amerika. Bibl. Lichenol. 58: 191-198. Kantvilas, G. & A. Vezda 2000. Studies on the lichen family Thelotremataceae in Tasmania. The genus Chroodiscus and its relatives. Lichenologist 32(4): 325-357 Knoph, J.-G. & C, Leuckert. 1994. Chemotaxonomic studies in the saxicolous species of the lichen genus Lecidella (Lecanorales, Lecanoraceae) in America. Nova Hedwigia 59:455-508. Lohtander, K. 1994. The genus Lepraria in Finland. Annales Botanici Fennici 31: 223-231. Looman, J. 1964. The distribution of some lichen communities in the Prairie Provinces and adjacent parts of the Great Plains. Bry. 67:209-224. Lumbsch, H. T., M. Plümper, R. Guderley & G. B. Feige 1997. The corticolous species of Lecanora sensu stricto with pruinose apothecial discs. Symb. Bot. Ups. 31(1): 131-162. Magnusson, A.H. 1932. Lichens from western North America, mainly Washington and Alaska. Ann. Crypt. Exot. 5: 16-38. Magnusson, A.H. 1933 Supplement to the monograph of the genus Acarospora. Ann. Crypt. Exot. 6:13-48. Magnusson, A.H. 1934. On the species of Biatorella and Sarcogyne in America. Ann. Crypt. Exot. 7: 115-134. Magnusson, A.H. 1939 (1940?). Western American lichens, mainly from Oregon. Meddel. Göteborgs Bot. Tragard 13: 237-253. Magnusson, A.H. 1944. Some species of Caloplaca from North America. Bot. Not. 1944: 63-79. Magnusson, A.H. 1944b. Studies in the Ferruginea group of the genus Caloplaca. Göteborgs Kungl. Vetenskaps- och Vitterhets-Sammhälles Handlingar, ser. B, (3): 1-71. Magnusson, A.H. 1947. On North American, non-saxicolous species of the genus Rinodina. Bot. Not. 1947: 32- 54. May, P.F. 1997. Ophioparma lapponica – a misunderstood species. Harvard Papers in Biology 2: 213-228. McCarthy, P. M. & T. Tønsberg. 1998. Porina radicicola, a new lichen from western North America. Lichenol. 30: 245-248. McCune, B. & L. Geiser. 1997. Macrolichens of the Pacific Northwest. Oregon State University Press, Corvallis. McCune, B. & R. Rosentreter. 1995. Distribution and ecology of Thelomma ocellatum in western North America. Evansia 12: 103-106. McCune, B. & T. Goward. 1995. Macrolichens of the Northern Rocky Mountains. Mad River Press, Eureka, California. 208 pp. McCune, B. 1982. Lichens of the Swan Valley, Montana. Bry. 85:13-21. McCune, B. 1984. Lichens with oceanic affinities in the Bitterroot Mountains of Montana and Idaho. Bry. 87:44- 50. McCune, B. 1996. Micarea botryoides new to North America. Evansia 13: 65-66 McCune, B. 1997. Ptychographa, a lichen genus new to North America. The Bryologist 100: 239-240. McCune, B. 1998. Lichens of granitic peaks in the Bitterroot Range, Montana and Idaho, USA. Pp. 281-294 in M. G. Glenn, R. C. Harris, R. Dirig, and M. S. Cole, editors, Lichenographia Thomsoniana: North American Lichenology in Honor of John W. Thomson. Mycotaxon Ltd., Ithaca, New York. McCune, B., R. Rosentreter & A. Debolt. 1997. Biogeography of rare lichens from the coast of Oregon. Pages 234-241 in: T. N. Kaye, A. Liston, R. M. Love, D.L. Luona, R. J. Meinke and M. V. Wilson (eds.), Conservation and Management of Native Plants and Fungi. Native Plant Society of Oregon, Corvallis. Merrill, G.K. 1913. New and interesting lichens from the state of Washington. The Bryologist 16: 56-59. Miller, H. A. & S. Shushan. 1964. The 1962 Foray in Oregon of the American Bryological Society. The Bryologist 67: 60-72.

12 Noble, W.J. 1980. Catillaria columbiana comb. nov. from western North America. The Bryologist 83: 71-73. Noble, W.J. 1982. The Lichens of the Coastal Douglas-Fir Dry Subzone. Ph.D. Thesis, Univ. British Columbia, 942 pp. Noble, W.J., Ahti, T., Otto, G.F., Brodo, I.M. 1987. A second checklist and bibliography of the lichens and allied fungi of British Columbia. - Syllogeus 61: 1-95. Nordin, A. 1999. Buellia species (Physciaceae) with pluriseptate spores: new and unrecorded species in North America. Bryologist 102:249-264. Nordin, A. 2000. Taxonomy and phylogeny of Buellia species with pluriseptate spores (Lecanorales, Ascomycotina). Symbolae Botanicae Upsalienses 33: 1-117. Orcutt, C.R. 1907. Botany of southern California. Lichens. American Plants 1: 240-245. Otto, G. 1983. Tholurna dissimilis The Bryologist 86: 263-265. Palmer, F., J. Staley & B. D. Ryan. 1990. Ecophysiology of microcolonial fungi and lichens in northeastern Oregon. New Phytol. 116: 613-620. Peterson, E.B. & J. Rikkinen 1998. Stenocybe fragmenta, a new species of Mycocaliciaceae with fragmenting spores. Mycologia 90(6): 1087-1090. Peterson, E.B. & J. Rikkinen 1999. Range extensions of selected pin lichens and allied fungi in the Pacific Northwest. The Bryologist 102(3): 370-376. Pike, L. 1972. Lichens and fleshy fungi of the H. J. Andrews Experimental Forest. Internal Reports 45, Coniferous Forest Biome--U.S. Analysis of Ecosystems, International Biological Program. Pike, L. 1973. Lichens and bryophytes of a Willamette Valley oak forest. Northwest Science 47(3): 149-158. Pike, L. 1976a (unpublished). Checklist of Oregon Lichens. Pike, L. 1976b (unpublished). A key to the genera of foliose lichens occurring in Oregon. Pike, L. 1976c (unpulbished). A simplified key to the genera of fruticose lichens occurring in Oregon (including lichens with 2-fold thalli). Pike, L. 1981. Tholurna dissimilis in Oregon. The Bryologist 75: 578-580. Pike, L., W. C. Denison, D. M. Tracy, M. A. Sherwood & F. M. Rhoades. 1975. Floristic survey of epiphytic lichens and bryophytes growing on old-growth conifers in western Oregon. The Bryologist 78(4): 389-402. Poelt, J. 1969. Bestimmungsschlüssel europäischer Flechten. Cramer, Lehre. 757 pp. Printzen, C. & T. Tønsberg 1999. The lichen genus Biatora in Northwestern North America. The Bryologist 102: 692-713. Printzen, C. & T. Tønsberg 2003. Four new species and three new apothecial pigments of Biatora. In: Jensen, M. (ed.) Lichenological Contributions in Honour of G.B. Feige. Bibliotheca Lichenologica, J. Cramer, Berlin, Stuttgart. Pp. 133-145. Printzen, C., Tønsberg, T., & Z. Palice 2002. Biatora aegrefaciens, rare but widespread. Graphis Scripta 13(2): 37-38. Printzen, C. 1995. Die Flechtengattung Biatora in Europa. Bibl. Lichenol. 60. J. Cramer, Berlin. Purvis, O.W., B. J. Coppins, D. L. Hawksworth, P. W. James, and D. M. Moore. 1992. The Lichen Flora of Great Britain and Ireland. Natural History Museum Publications, London. Rhoades, F.M. 1984. Existing and potential impact of SO2 air pollution on lichens and higher plants of the region around Grays Harbor, Washington. A report for the United States Borax and Chemical Corporation. R&E:0900c:tl:Rev.1. Appendix E. Rhoades, F.M. 1988. Re-examination of baseline plots to determine effects of air quality on lichens and bryophytes in Olympic National Park. Report SP-4450-88-13. Northrop Environmental Services. Research Triangle Park, NC. 139 pp. + appendices. Rhoades, F.M. 1992 [unpublished]. Maiden Peak Ridge Study with Rich Fonda. Rhoades, F.M. 1993 [unpublished]. Species of lichens reported from the Olympic Peninsula, Washington. Rikkinen, J. 1998. Chaenotheca olivaceorufa (Caliciales) new to North America. The Bryologist 101: 558-559. Rikkinen, J. 1999. Two new resinicolous Chaenothecopsis (Mycocaliciaceae) from western North America. Bryol. 102: 366-369 Rikkinen, J. 2003. Calicioid lichens and fungi in the forests and woodlands of western Oregon. Acta Botanica Fennica 175: 1-41. Rikkinen, J. 2003b. New resinicolous ascomycetes from beaver scars in western North America. Annales Botanici Fennici 40: 443-450. Rikkinen, J. 2003c. Chaenothecopsis nigripunctata, a remarkable new species of resinicolous Mycocaliciaceae from western North America. Mycologia 95(1): 98-103. Ropin, K. & H. Mayrhofer 1995. Über corticole Arten der Gattung Rinodina (Physciaceae) mit grauem Epihymenium. In: Farkas, E.E., Lücking, R., Wirth, V. (eds.): Scripta Lichenologica – Lichenological papers dedicated to Antonín Vezda. Bibliotheca Lichenologica, J. Cramer, Berlin, Stuttgart. Pp. 361-382. Rosentreter, R. 2001. New, rare and interesting lichen taxa collected on the 2000 ABLS field trip “Oregon Steppe to the Coast” led by Dr. Bruce McCune, Aug. 10-13, 2000. Evansia 18(4): 129-132. Rosso, A. L., B. McCune, T. Tønsberg & C. Printzen. 1999. Lichens of an old-growth forest in a little explored area of western Oregon, U.S.A. Evansia 16: 137-140. 13 Ryan, B. 1985a. Lichens of Chowder Ridge, Mt. Baker, Washington. Northwest Science 59(4): 279-293. Ryan, B. 1985b. New records of lichens from Washington state. Evansia 2(3): 33-35. Ryan, B. 1988a. Marine and maritime lichens on serpentine rock on Fidalgo Island, Washington. The Bryologist 91: 186-190. Ryan, B. 1988b. Zonation of lichens on a rocky seashore on Fidalgo Island, Washington. The Bryologist 91: 167-180. Santesson, R. 1984. The lichens of Sweden and Norway. Swedish Mus. Nat. Hist., Stockholm. 333 pp. Sheard, J.W. & H. Mayrhofer 2002 [2003]. New species of Rinodina (Physciaceae, lichenized Ascomycetes) from western North America. The Bryologist 105: 645-672. Sheard, J.W. & T. Tonsberg 1995. Rinodina stictica, a new corticolous, sorediate lichen species from the Pacific Northwest of North America. The Bryologist 98(1): 41-44. Sheard, J.W. 1992. The lichenized Ascomycete genus Hafellia in North America. The Bryologist 95: 85 Sheard, J.W. 1995. Disjunct distributions of some North American, corticolous, vegetatively reproducing Rinodina species (Physciaceae, lichenized Ascomycetes). Herzogia 11: 115-132. Sheard, J.W. 1997. A synopsis of the species of Amandinea (Lichenized Ascomycetes, Physciaceae) as presently known in North America. Bryologist 100:159-169. Sherwood, M.A. & Coppins, B.J. 1980. Xerotrema, a new genus of odontotremoid fungus from Scotland. Notes from the Royal Botanic Garden Edinburgh 38: 367-371. Sierk, H. 1964. The genus Leptogium in North America north of Mexico. The Bryologist 67: 245-317. Sipe, F. P. 1939. Lichens of the upper Willamette Valley. The Bryologist 42(1): 12-16. Sipe, F. P. 1943. Lichens of Crater Lake National Park. The Bryologist 46(4): 135-138. Sliwa, L. & C.M. Wetmore 2000. Notes on the Lecanora varia group in North America. Bryologist 103(3): 475- 492. Spribille, T. & M. Hauck 2003. Pyrrhospora gowardiana, a new montane lichen from western North America (Lecanoraceae, lichenized Ascomycetes). The Bryologist 106(4): 560-564. Spribille, T. & S. Gross. [unpubl., in prep.] Calicioid lichens and related non-lichenized ascomycetes of the inland Pacific Northwest. Unpubl. MS, 6 pp. Spribille, T. 2002. Additions to the lichen flora of Alberta, Canada from Crowsnest Pass. Evansia 19(1): 20-21. Stansell, V. & E. B. Peterson 1997. Joint field trip to southwest Oregon by CALS and Northwest Lichen Guild, October 19/20, 1996. Bulletin of the California Lichen Society 4: 12-14. Tehler, A. 2002. Sigridea. In: Nash, TH, III, Ryan, B.D., Gries, C., Bungartz, F. (eds.): Lichen Flora of the Greater Sonoran Desert Region. I. Lichens Unlimited, Arizona State University, Tempe, Arizona, pp. 461- 462. Thomson J.W. & I. M. Brodo. 1969 (unpubl.) Detailed itinerary of Lichenological Field Trip, XI International Botanical Congress Thomson, J.W. 1969. Catalogue of the lichens of Washington State. Prepared for the XI International Botanical Congress, Seattle. 59 pages. Thomson, J.W. 1979. Lichens of the Alaskan Arctic Slope. University of Toronto Press, Toronto. 314 pages. Thomson, J.W. 1984. American Arctic Lichens. 1. The Macrolichens. Columbia University Press, New York. 504 pages. Thomson, J.W. 1997. American Arctic Lichens 2. The Microlichens. University of Wisconsin Press, Madison, Wisconsin. 675 pp. Tibell, L. & A. Titov 1995. Species of Chaenothecopsis and Mycocalicium (Caliciales) on exudate. Bryologist 98(4): 550-560. Tibell, L. 1975. The Caliciales of boreal North America. Symbolae Botanicae Upsaliensis 21(2): 1-128. Tibell, L. 1976. The genus Thelomma. Bot. Not. 129: 221-249. Tibell, L. 1978. The genus Microcalicium. Bot. Notiser 131: 229-246. Tibell, L. 1980. The lichen genus Chaenotheca in the Northern Hemisphere. Symbolae Botanicae Upsalienses 23: 1-65. Tibell, L. 1991. A new species of Stenocybe from Western North America. The Bryologist 84: 413-415. Timdal, E. 1984. The genus Hypocenomyce (Lecanorales, Lecideaceae), with special emphasis on the Norwegian and Swedish species. Nordic Journal of Botany 4: 83-108. Timdal, E. 2001. Hypocenomyce oligospora and H. sierrae, two new lichen species. Mycotaxon 77: 445-453. Tønsberg, T. & A. Henssen 1999. Additions to the lichen flora of North America VIII. Santessoniella grisea new to North America. Evansia 16: 184. Tønsberg, T. & B. McCune 2001. Additions to the lichen flora of North America. X. Buellia arborea. Evansia 18(4): 128. Tønsberg, T. & B.J. Coppins 2000. Additions to the lichen flora of North America. IX. Micarea alabastrites and M. synotheoides. Evansia 17(4): 135-136. Tønsberg, T. & I.M. Brodo 1992. Enterographa zonata and Opegrapha gyrocarpa new to North America. The Bryologist 95(2): 225-226.

14 Tønsberg, T. 1990. Japewia subaurifera, a new lichen genus and species from north-west Europe and western North America. Lichenologist 22: 205-212. Tønsberg, T. 1991. Gyalideopsis anastomosans new to North America. Graphis Scripta 3: 69. Tønsberg, T. 1992. Rinodina sheardii, a new lichen species from northwest Europe and northwest North America. The Bryologist 95(2): 216-217. Tønsberg, T. 1992. The sorediate and isidiate, corticolous, crustose lichens in Norway. Sommerfeltia 14: 1-331. Tønsberg, T. 1993a. Additions to the lichen flora of North America. The Bryologist 96(1): 138-141. Tønsberg, T. 1993b. Additions to the lichen flora of North America II. The Bryologist 96: 629-630. Tønsberg, T. 1994. Additions to the lichen flora of North America. III. Halecania viridescens and Opegrapha sorediifera. Evansia 11(3): 100-101. Tønsberg, T. 1995. Additions to the lichen flora of North America IV. Scoliciosporum sarothamni. Evansia 12: 27-30. Tønsberg, T. 1995. Additions to the lichen flora of North America V. Arthonia stellaris. Evansia 12: 66-67. Tønsberg, T. 1997. Additions to the lichen flora of North America VI. The Bryologist 100: 522-524. Tønsberg, T. 1997b. Lichenes Isidiosi et Sorediosi Crustacei Exsiccati. Fasc. 1 (Nos. 1-25). Distributed by Herbarium BG, University of Bergen, Norway. Tønsberg, T. 1998. Additions to the lichen flora of Norway and Sweden. Graphis scripta 9: 27-31. Tønsberg, T. 1999a. Additions to the lichen flora of North America. VII. Some species found on Waadah Island, Washington. The Bryologist 102: 133-134. Tønsberg, T. 1999b. Lichenes Isidiosi et Sorediosi Crustacei Exsiccati. Schedae. Fascicle 2 (Nos 26-50). Bergen. 10 pp. Tønsberg, T. 2002. Additions to the lichen flora of North America XI. The Bryologist 105: 122-125. Tønsberg, T. 2004. Chrysothrix. In Nash III, T.H., Ryan, B.D., Diederich, P., Gries, C., Bungartz, F. (eds). Lichen flora of the Greater Sonoran Desert Region. Volume II (most of the microlichens, balance of the macrolichens, and the lichenicolous fungi). Lichens Unlimited, Tempe, Arizona. Pp. 62-63. Tønsberg, T. 2004. Lepraria. In Nash III, T.H., Ryan, B.D., Diederich, P., Gries, C., Bungartz, F. (eds). Lichen flora of the Greater Sonoran Desert Region. Volume II (most of the microlichens, balance of the macrolichens, and the lichenicolous fungi). Lichens Unlimited, Tempe, Arizona. Pp. 322-329. Triebel, D. 1989. Lecideicole Ascomyceten. Eine Revision der obligat lichenicolen Ascomyceten auf lecideoiden Flechten. Bibliotheca Lichenologica 35: 1-278. Tuckerman, E. 1858. Lichens. In: U.S. Ward Dept. Explorations and Surveys for a Railroad Route from the Missisippi River to the Pacific Ocean 6: 94. (See collected works of Tuckerman for this and other articles by him, which need to be checked) Tuckerman, E. 1862. Lichenes. In: Wilkes, C., U.S. Exploring expedition during the years 1838-1842. (Bot.): 113-152. Tuckerman, E. 1874. Two Oregon lichens. Bull. Torrey Bot. Club 5(4): 20. Tuckerman, E. 1882. A synopsis of the North American lichens. Part I. S.E. Cassino, Boston. Tuckerman, E. 1888. A synopsis of the North American lichens. Part. II. Comprising the Lecideacei, and (in part) the Graphidacei. - New Bedford, Mass. 176 pp. Vezda, A. 1986. Neue Gattungen der Familie Lecideaceae s.lat. (Lichenes). Folia geobot. Phytotax. 21: 199-219 Vitt, D. H., J. E. Marsh & R. B. Bovey. 1988. Mosses, Lichens and Ferns of Northwest North America. University of Washington Press, Seattle. Weaver, J. E. 1917. A study of the vegetation of southeastern Washington and adjacent Idaho. Univ. of Nebraska Studies 17: 1-333. Weber, W.A. 1975. Lichenes Exsiccati. Distributed by the University of Colorado. 14 pp. [the content should be repeated in Weber 1981 in whole] Weber, W.A. 1981. Lichenes Exsiccati distributed by the University of Colorado Museum, Boulder: fascicles 1- 15, nos. 1-600, 1961-1979. Mycotaxon 13(1)85-104. Wetmore, C. M. 1967. Lichens of the Black Hills of S. Dakota and Wyoming. Publications of the Museum, Mich. State Univ., Biological Series 3:209-464. Wetmore, C.M. 1983. Lichens of the air quality Class 1 National Parks. Final Report, National Park Service Contract CX 0001-2-0034. Denver, Colorado. Willey, H. 1890. A synopsis of the genus Arthonia. New Bedford, Mass. Will-Wolf, S. 1998. Lichens of Badlands National Park, South Dakota, USA. . Pp. 323-336 in M. G. Glenn, R. C. Harris, R. Dirig, and M. S. Cole, editors, Lichenographia Thomsoniana: North American Lichenology in Honor of John W. Thomson. Mycotaxon Ltd., Ithaca, New York. Wong, P.Y & I.M. Brodo 1990. Significant records from the lichen flora of southern Ontario, Canada. The Bryologist 93(3): 357-367. Wright, D.M. 1998. Collections from the 1998 Northwest Lichen Guild – CALS field trip to the Pilot Rock area, Siskiyou Mountains, Jackson County, Oregon, May 23, 1998. Bulletin of the California Lichen Society 5: 28-37.

15