Gallery of Past Featured Fungi
Click on image to view associated article
Click on image to view associated article
Cause of Rhododendron Bud Blast
Also known by various synonyms such as Briosia azaleae and Pycnothysanus azaleae, scientists recently found the fungus on several Rhododendron species and cultivars not previously known to be affected by this pathogen in the Pacific Northwest. For further details, click on the photograph.
A mycorrhizal associate of Populus trichocarpa.
Cortinarius is a very large, taxonomically complex genus of ectomycorrhizal mushrooms that occurs widely in the Pacific Northwest as well as many other parts of the world. Researchers recently determined that Cortinarius lucorum occurs with Populus trichocarpa in low-elevation forests and is distinct from the morphologically-similar species Cortinarius saturninus. To view the article reporting this research, click on the photo (article file size is 717 kb).
Featured Fungus Number 3
A fungicolous fungus occurring on the powdery mildew Phyllactinia guttata.
Cladosporium uredinicola recently was found growing on the plant parasitic powdery mildew Phyllactinia guttata. One of many fungicolous fungi (fungi that grow on other fungi), C. uredinicola is known to be a widespread parasite of rust fungi. On P. guttata, C. uredinicola was observed primarily on penicillate cells, specialized structures involved in attaching ascocarps to new substrates during dispersal. To view the article reporting this research, click on the photo (article file size is 187 kb).
Featured Fungus Number 4
An ectomycorrhizal mushroom occurring in low elevation conifer forests.
Cortinarius rubellus is a relatively uncommon ectomycorrhizal mushroom in our region, occurring in low elevation conifer forests. It has been reported from Europe and North America in both conifer and hardwood forests and likely occurs in most north temperate forest regions of the world. It can be locally abundant in moist boreal forests with spruce. It produces a renal toxin, Orellanine, and is a dangerously poisonous mushroom, www.namyco.org/toxicology/poisoning.html. For more information, click on the photograph (article file size is 601 kb).
Featured Fungus Number 5
A Cladosporium-like fungus originally described by the first person to earn a Ph.D. at the State College of Washington (WSU).
Alternaria malorum (Ruehle) U. Braun, Crous & Dugan (= Cladosporium malorum Ruehle) is a Cladosporium-like hyphomycete whose transfer to Alternaria was supported by sequence data from ITS and 18S rRNA regions, metabolite production, structure of conidiogenous loci and, in A. malorum var. polymorpha, transient production of dictyoseptate conidia terminating in beak-like projections. First reported on apple from Washington State by George Ruehle (the first person to receive a PhD at the State College of Washington in Pullman), A. malorum has been isolated from an increasing number of hosts and substrata, and is an opportunistic pathogen on a variety of ripe fruits. For more details, click on the photo to download the accompanying article. [file size: 145 kb]
Featured Fungus Number 6
A classic old-growth-associated lichen of the Pacific Northwest.
Pseudocyphellaria rainierensis Imsh. is an uncommon to rare cyanolichen that is strongly associated with old-growth forests of the Pacific Northwest, west of the Cascade crest. Like Lobaria oregana, this lichen is believed to be dispersal-limited. It reproduces by isidia and lobules. Apothecia are very rare. One of the strongholds for this species is in the Blue River watershed in the Oregon Cascades. For more information on the ecology of this species in relation to canopy structure, historical disturbance, and environment click on the photo to download the related paper by Berryman and McCune. [file size: 323 kb]
Featured Fungus Number 7
The Pacific Golden Chanterelle.
The Pacific Golden Chanterelle, Cantharellus formosus E.J.H.Corner, was described from Vancouver Island in 1966. For decades this name was ignored and the European name C. cibarius was applied to the most common Chanterelle in our region. DNA analysis showed that C. cibarius is not the same as C. formosus, thus the application of the latter name to our species. The Pacific Golden Chanterelle is commonly collected by pot hunters and sold in market throughout the Pacific Northwest and elsewhere in North America. Productivity varies from year to year as does the price; in 1992 an estimated 515 metric tons of chanterelles were exported from our region, mostly to Europe and Turkey. Chanterelles grow in association with the roots of a variety of tree species, usually fruiting after trees are ten or so years old. The Pacific Golden Chanterelle is long lived and rather resistant to insect attack. It is an excellent edible species particularlyhigh in Vitamin D. Click on the photo to view Redman et al.'s recent article on genetic structure of populations in this interesting fungus. [file size: 459 kb] Photo courtesy Ben Woo.
Featured Fungus Number 8
Cause of white rust of Brassicaceae
For many years considered to be a fungus, Albugo candida is an oomycete more closely related to algae than fungi. It is an obligate plant parasite, requiring a live host to grow and reproduce. Gardeners and vegetable growers know it as the cause of white rust disease of a wide range of plants in the cabbage family (Brassicaceae). Albugo candida recently was found in Seattle parasitizing plants of Aurinia saxatilis (common name: Basket of Gold), a common rock garden plant in western Washington. This is thought to be the first record of A. candida on this host in North America. For more information, click on the photo to read the accompanying article. [file size: 513 kb]
Featured Fungus Number 9
Dendrocollybia racemosa parasitizing Russula crassotunicata
Dendrocollybia racemosa is a small, collybioid mushroom very similar in size and appearance to Collybia tuberosa and its relatives. Species in both genera are frequently associated with dead, decaying mushroom sporocarps, and with the exception of one species (C. cirrahata) form sclerotia. Dendrocollybia racemosa was recognized in Europe by early mycologists including E. M. Fries and C. Persoon. This fungus produces short branches on its stipe, hence the name racemosa, and produces black sclerotia (associated with decaying Russula crassotunicata and perhaps other Russulaceae), as seen in the photograph. This widespread species occurs in various habitats but it is uncommonly collected in our region and is generally considered a rare species by most workers. Originally D. racemosa was placed in the genus Collybia sensu lato; DNA sequence analyses show that phylogenetically it is a distinct species. To learn more, click on the photograph to download the article by Machnicki and co-authors [file size: 365 kb]
Featured Fungus Number 10
Chasmothecial appendages of Erysiphe flexuosa
Erysiphe flexuosa is a powdery mildew fungus with unusual flexuous chasmothecial appendages (hence the species epithet flexuosa). Because appendages are also uncinate (apices are recurved), the fungus previously was assigned to the genera Uncinula or Uncinuliella by various authors. An obligate parasite of Aesculus species, the fungus first was described in eastern North America during the 19th century. Within the past few years it has been reported throughout much of Europe. The fungus recently was found in western North America, in eastern Washington and northern Idaho. To read the article reporting on this research, click on the accompanying photo. [file size: 1358 kb]
Featured Fungus Number 11
The quintessential late-successional macrolichen of Arctic environments
Cladina stellaris (Opiz) Brodo is a terricolous macrolichen with a circumpolar distribution. This species contributes to the overall high lichen cover and diversity of late-successional sites in tundra environments of northwestern Alaska. Although present in lowland habitats, C. stellaris occurs mostly frequently in drier areas with exposed bedrock or loose rock. From a ground-level vantage point, the lichens in this photo, about seven cm tall, demonstrate the prolific communities that dominate some areas despite competition from vascular plants (in this case, Salix pulchera). For more information on the ecology of terricolous macrolichen communities in relation to succession and the environment click on the photo to download the related paper by Holt, McCune and Neitlich. [file size: 2440 kb]
Featured Fungus Number 12
Conidium of Erysiphe polygoni
A cosmopolitan parasite of buckwheat, knotweeds and docks
The name Erysiphe polygoni DC. once was applied to powdery mildew fungi on an extraordinarily broad range of hosts, including beets, legumes, cucurbits and many others. Under current taxonomic concepts, its hosts are restricted to the Polygonaceae. Records from USDA databases document E. polygoni on multiple genera in this family, including Eriogonum (wild buckwheat), Fagopyrum (buckwheat), Polygonum, Fallopia and Persicaria (knotweed), and Rumex (dock). Even for E. polygoni s. str. (restricted to the Polygonaceae), much remains unknown with regard to host specificity. Erysiphe polygoni recently was reported on curly dock in the Pacific Northwest, where it is also common on prostrate knotweed ( P. aviculare ). For more information, click on the photo to download the article by Dugan and Glawe. [file size: 502 kb]
Featured Fungus Number 13
Cause of powdery mildew of Rhododendron species in the Pacific Northwest
Erysiphe azaleae is a widespread fungus parasitizing Rhododendron species in the Pacific Northwest. The fungus produces ascocarps with elaborate, dichotomously- branched appendages involved in dispersal and attachment of the ascocarps to new substrates prior to overwintering. For more than a century this fungus was classified in the genus Microsphaera, partly on the basis of the distinctive ascocarp appendages. However, the old name Microsphaera was discarded after recent research in Asia and Europe indicated that the ascocarp appendages were an unreliable indicator of affinity at the genus level. For more information about current genus concepts for powdery mildew fungi, click on the photo that shows the appendaged ascocarps of this fungus. [file size: 4062 kb]
Featured Fungus Number 14
The most abundant fruticose lichen in the Sierra Nevada
The most conspicuous and abundant lichens in the Sierra Nevada are the fluorescent chartreuse Letharia species (wolf lichens). Although nearly absent at the lowest elevations, with increasing elevation the conifer trunks and branches become coated with a stunning abundance of bright yellow, fruticose Letharia vulpina and L. columbiana. Letharia has distinctive features that set it apart from other green-algal macrolichens: it is the only tufted, fruticose lichen in the Sierra Nevada that is abundant; it contains a secondary metabolite (vulpinic acid) that is toxic to many herbivores and microbes, strongly absorbs UV-A, UV-B, and UV-C radiation, and fluoresces visible light; and it forms the bulk of the lichen biomass in the sequoia groves. For more information on lichen ecology in the Sierra Nevada, click on the photo of Letharia vulpina on an Abies trunk in a giant sequoia grove. [file size: 437 kb]
Featured Fungus Number 15
Germinating conidium (asexual spore) of Oidium ericinum
Powdery mildew fungi are well-adapted obligate parasities that usually do not kill their hosts. Nonetheless, they frequently cause significant financial losses when they render fruits or berries unusable or ruin the appearance of ornamental plants. Oidium ericinum recently was found attacking Leucothoë axillaris (Ericaceae, common names: coast leucothoe, coastal doghobble) at a commercial nursery in Oregon. The infected plants, valued at several hundred thousand dollars, were unfit for sale. The fungus was identified on the basis of features of the conidial state; the sexual state of this parasite of L. axillaris remains unknown. For more information, click on the accompanying photo to see the article by Putnam and Glawe. [file size: 733 kb]
Featured Fungus Number 16
A widely distributed ectomycorrhizal fungus
Russula crassotunicata was described in 1938 by Rolf Singer from material collected by Alex Smith in Olympic National Park, Washington in 1935. Robert Shaffer published further details on the species in Lloydia (1970, 33:50). The species is easily recognized by its more-or-less compact habit of growth; the thick, rubbery cap cuticle which is easily separated from the cap context, commonly becoming split and cracked with age; its whitish buff to pale yellowish coloration, and tendency to discolor yellowish brown; and an acrid taste, especially of the gills. It is ectomycorrhizal and occurs in conifer and mixed conifer-hardwood forests. It occurs from northern California into western Canada and across the boreal forest zone into northeastern North America. It commonly appears on foray lists from across its range and has been the subject of ecological studies in western North America. It fruits from early summer into the fall seasondepending on location and environmental conditions. Recently it was shown to be colonized by the mycosaprobic basidomycete Dendrocollybia racemosa which forms sclerotia interspersed among the gills of R. crassotunicata. To see the paper reporting on this relationship, click on the photograph. (Photograph courtesy of Ben Woo.) [file size: 365 kb]
Featured Fungus Number 17
A widespread pathogen of Asteraceae
Among the many powdery mildew fungi occurring on cultivated plants, perhaps none is more frequently encountered than Golovinomyces cichoracearum, formerly known as Erysiphe cichoracearum. Distinguished by conidiophores that form chains of conidia, papillate appressoria and chasmothecia with mycelioid appendages, this species can be found on many members of the Asteraceae (sometimes known as the sunflower family). Golovinomyces cichoracearum is a vigorously-growing parasite of leaves, stems, and flowers. The fungus can spoil the appearance of ornamental plants, and reduces plant vigor by diverting photosynthates to support mycelial growth and sporulation. The known Pacific Northwest host range for this fungus recently was enlarged to include garden lettuce. For more information, click on the accompanying photo. [file size: 354 kb]
Featured Fungus Number 18
A dominant lichen in forest canopies of the Cascade Range
Alectoria sarmentosa (Ach.) Ach. is one of the most conspicuous lichens of mid to upper elevation forests of the Cascade Range. Forming long pale yellow green beards, it can achieve a biomass of well over 1 T/ha dry weight. The photo shows apothecia, which are only erratically produced. The species reproduces and spreads primarily by fragmentation. As one goes up in elevation on the west slope of the Cascades in Oregon, Alectoria sarmentosa increases in abundance, achieving maximum biomass in forests above 1000 m. For more information on the ecology of this species in relation to canopy structure, historical disturbance, and environment, click on the photo to download the related paper by Berryman and McCune (scale bar = 1 mm). [file size: 323 kb]
Featured Fungus Number 19
A cosmopolitan Ascomycete on decaying plants
Among the most common fungi found on senescent or decaying plant material, Davidiella (Mycosphaerella) tassiana is a cosmopolitan fungus isolated very frequently in its anamorphic state, Cladosporium herbarum. It occurs on a wide range of plant hosts and has been demonstrated to parasitize live hosts. Sexually sterile pseudothecia of Davidiella tassiana recently were found to produce the asexual C. herbarum state. Conidiophores originated directly from pseudothecial papillae, as shown in the accompanying photograph. Production of an anamorph directly from the teleomorph (or stromata surrounding the teleomorph) has been documented for other ascomycetes, but this mode of reproduction appears previously undocumented for D. tassiana. For information on its possible ecological role on one host, common teasel, click on the accompanying photo. [file size: 261 kb]
Featured Fungus Number 20
A common phylloplane fungus with dispersible chasmothecia
Chasmothecia (ascocarps) of Phyllactinia guttata exhibit striking adaptations for dispersal. Each chasmothecium forms long appendages that flex downward when mature, lifting it from the leaf surface. When the chasmothecium falls from the leaf to become airborne the appendages function like vanes, orienting it so the dorsal side is to the front as it moves through the air. The dorsal surface is covered with a sticky, dome-shaped mass of penicillate cells that attach the chasmothecium to whatever object it strikes. The chasmothecium then overwinters in its new location and during the next spring discharges ascospores to begin a new cycle of infection and reproduction on a new host. Click on the accompanying photo of a chasmothecium for more information about Phyllactinia species and other powdery mildews. [file size: 4062 kb]