page_title: Suillus pungens
section_title: Ecology, habitat and distribution
hierarchical_section_title: Suillus pungens / Ecology, habitat and distribution
caption_attribution_description: English: Fruit bodies of the fungus Chroogomphus vinicolor (Peck) O.K. Mill. Specimens photographed in Oneida Co., New York, USA.
context_page_description: Suillus pungens, commonly known as the pungent slippery jack or the pungent suillus, is a species of fungus in the genus Suillus. The fruit bodies of the fungus have slimy convex caps up to
  14 cm wide. The mushroom is characterized by the very distinct color changes that occur in the cap throughout development. Typically, the young cap is whitish, later becoming grayish-olive to reddish-brown or a mottled combination of these colors. The mushroom has a dotted stem up to 7 cm long, and 2 cm thick. On the underside on the cap is the spore-bearing tissue consisting of minute vertically arranged tubes that appear as a surface of angular, yellowish pores. The presence of milky droplets on the pore surface of young individuals, especially in humid environments, is a characteristic feature of this species. S. pungens can usually be distinguished from other similar Suillus species by differences in distribution, odor and taste. The mushroom is considered edible, but not highly regarded.
  An ectomycorrhizal species, S. pungens forms an intimate mutualistic relationship between its underground mycelium and the young roots of the associated host tree.
context_section_description: Suillus pungens is an ectomycorrhizal (EM) basidiomycete that forms symbiotic relationships almost exclusively with Monterey pine (Pinus radiata) and bishop pine (Pinus muricata); some collections have been made under knobcone pine (Pinus attenuata) and ponderosa pine (Pinus ponderosa), but only within the range of Monterey pine. All these trees have small scattered natural ranges largely restricted to California. An EM symbiosis is a mutualistic relationship between an EM fungus and the root tip of a compatible EM plant. The fruit bodies of Suillus pungens grow solitarily, scattered or in groups in humus. They are often found growing near fruit bodies of Chroogomphus vinicolor and Helvella lacunosa. Suillus pungens is often the most abundant Suillus in the San Francisco Bay Area. The type collection was made on the campus of San Francisco State University in San Francisco, where it occurs in abundance during the fall and winter seasons. Although it occurs most frequently in the autumn and winter, it is one of the few species of Suillus that continue to fruit sporadically throughout the year, especially in wet weather. It has also been identified in the southeastern Sierra Nevada and on Santa Cruz Island.
  A genet is a group of genetically identical individuals that have grown in a given location, all originating vegetatively from a single ancestor. Once established, genets vegetatively spread hyphae out from the root tip into the soil and may connect two or more trees to form a network of mycorrhizae. In field studies, the approximate size of fungal genets is typically estimated by collecting and mapping fruit bodies on a site, determining which fruit bodies are genetically identical by either somatic incompatibility (a method fungi use to distinguish self from non-self by delimiting their own mycelia from that of other individuals of the same species) or various molecular techniques, and then determining the distance between identical fruit bodies. In a 1996 study, mycologists Monique Gardes and Thomas Bruns hypothesized that S. pungens, an abundant fruiter in pine forests, would be dominant on the roots of the pine trees. However, by sampling underground ectomycorrhizae in addition to above-ground fruit bodies, they found that the fungus can fruit prolifically while occupying only a small fraction of the ectomycorrhizal root assemblage, which was otherwise dominated by Russula species and Tomentella sublilacina. Gardes and Bruns hypothesized that the disparity between above- and below-ground representation may be because the fungus invests less energy in vegetative growth and persistence and more in fruiting, or alternatively, because the species is particularly efficient at acquiring carbon from its hosts and so needs to colonize only a few rootlets to obtain enough to allow abundant fruiting. A 1998 study by Pierluigi Bonello and colleagues used single-strand conformation polymorphism analysis to detect minute genetic differences among S. pungens genets, and showed that most of the fruiting occurred from a single large genet. This result indicates that the fungus persists because of extensive vegetative growth, rather than frequent establishment of new genets from spores, and that it uses carbon resources efficiently. The study also described an S. pungens genet with an area of approximately 300 m² (3,200 sq ft) and a span greater than 40 m (130 ft) across, which was at the time the largest EM fungal genet reported. The large S. pungens genet was not detected after wildfire, demonstrating that it did not survive in the absence of a host, and suggesting that spores are the primary means by which the fungus recolonizes after a fire.
caption: S. pungens is often found growing near Chroogomphus vinicolor (pictured).
exif: {}