Forms ectomycorrhiza with Pinus sylvestris and grows mainly on dry and nutrient poor sedimentary soils in open pine forests, possibly favored by fire. Occurs mainly in older, not clear-cut forest, both virgin and thinned forests. A well-known indicator species for old-growth forests of conservation value.Usually only a few mature individuals occur at each location. Individuals are considered to be very old and reestablishment of the species appears to be rare after clear cutting. It is rarely found in pine plantations. Has been and is being negatively impacted by clear cutting and reducing areas of Scots pine old growth outside protected areas.Probably favored by green tree retention forestry and veteran trees. Is estimated to have declined and to continuously decline at the global scale due to decreasing areal of old growth pine forests and an apparent poor ability to spread and re-establish in managed forest after clearcutting. Red listed in five European countries.
Preliminary global Red List assessment; NT (A2c+3c+4c).
To large and widespread population to qualify for evaluation under criteria B-D.
European Red List assessment; NT (A2c+3c+4c)
Cause: 15-30% decline in habitat quality (old growth Scots pine forest)due to logging. Evaluation period 50 years (= 3 generations according to the recommendation of Dahlberg & Mueller, 2011). Large scale modern forest management/clearcutting operating in Fennoscandia, Russia and also in N. America have significantly reduced and will continuously significantly reduce the potential amount of habitat. In Fennoscandia, the past, ongoing and future population decline inferred from habitat change, i.e. clear cutting, been estimated from forest statistics of potential habitat decline to be at least 15-30%. Red listed in all Fennoscandian countries. Rare/extinct in central Europe. Red-listed in 3 provinces in Russia.
Need more information: status and distribution in North America.
Suggested red-listing in Europe NT as above, global NT?
but consider perplexa, looks like leucomelana but grows with pine. Present in Turkey? is present in NAM
The boreal parts of Asia, North America and Europe
The species exclusively occurs in boreal old-growth forests of Scots pine (Pinus sylvestris) with the majority of the European localities known from Sweden and Finland and a possibly high number in Russia. Forest where it occurs are primarily threatened by clearcutting and possibly it is also negatively affected by nitrogen fertilization of forests.
The species seems to have poor ability to spread and establish in forest after clearcutting. This is probably due to increasingly low proportion of old-growth-pine-forest where it occurs and hence lower likeliness of the species to re-establish from spores. It may also depend on that the species is considered to form long-lived individual mycelia, probably several decades and possibly several centuries old and that it evolutionary has been selected to have a slow population dynamics. Historicaly, boreal forest fires commonly has been low-intense with a high degree of tree survival, and hence with a high likelyness for mycelia of ectomycorrhizal fungi to be very old. In Fennoscandia, old-growth pine forest is estimated to have declined with > 30% (Norway and Sweden) and >15% (Finland) since 1960 (during the last 50 years). Clear-cutting management was introduced in large scale in these countries around 1950 and on average 1% of the productiver forest land is clear cut annualy. Boletopsis grisea is yet only rarely observed in forest resulting from clearcutting, hence close to seed trees or retention trees.
Population Trend: Deteriorating
Forms ectomycorrhiza with Scots pine (Pinus sylvestris). Occurs predominately in open oligotrophic (nutrient poor) boreal pine forests with lichens ericaceous (Calluna and Vaccinium) undergrowth vegetation on dry acidic sandy soils. It is common in old growth pine forests on sediment/sandy soils. It is also still frequent in old pine forests which has been subjected to selective cutting since early 1800 or longer, where it typically associate with old pines. These forest have historically naturallly been subjected to low-intense forest fires with a high degree of tree survival.
The mycelia of the fungus is considered to potentially be as old as the pines, or older. Probably, the mycelia of the fungus survive forest fires if the Scots pine tree they are associated with does. In Poland the fungus also occurs on inland sand dunes with pine, in France it is reported in pine forests mixed with Cedrus.
It is primarily threatened by clearcutting of old-growth pine forests and possibly also negatively affected by nitrogen fertilization of forests. It is rarely observed in forest regenerated after clearcutting.Hence conversion of old growth forests to managed forest, i.e. reduced amount of habitat, is the main cause of the decline.
Setting aside Scots pine forest reserves where the species have good populations. At these forests, natural or prescribed burning should be considered to maintain desired forest dynamics. As B. grisea is a mycorrhizal fungus and the mycelia probably potentially is long-lived to very long-lived, it is an appropriate consrvation action to maintain living trees where it occurs. It is possible that a sufficient number of retetion trees, if the forest is cut, may enable B. grisea to survive the cutting. In this case it is important to ensure that as many retetion trees as possible are located where the mycelia of the fungus is growing, e.g. where the sporocarps have been observed.
A better understandibng of the specie’s population dynamic would facilitate a better management, e.g.at what conditions it may establish, the demographic structure within populations and the pattern (and causes) of individual mycelia. Also to what degree seed trees and retention trees in managed forest may maintain the species at locations.
Dahlberg A & Croneborg H. 2003. 33 threatened fungi in Europe. Complementary and revised information on candidates for listing in Appendix I of the Bern Convention T-PVS (2001) 34 rev 2.
Dahlberg A & Mueller G. 2011. Applying IUCN red-listing criteria for assessing and reporting on the conservation status of fungal species. Fungal Ecology 4: 1-16
Gärdenfors, U (ed), 2010. Red-listed Species in Sweden 2010. ArtDatabanken, SLU, Uppsala.
Kålås J A, Viken V, Henriksen S and. Skjelseth S (eds). 2010. Norwegian Biodiversity Information Centre, Norway.
Nitare J, 2005. Indicator Species for Assessing the Nature Conservation Value of Woodland Sites – a flora of selected cryptogams [In
Swedish]. Skogsstyrelsens Förlag, Jönköping.
Otto P, 2011. Ecology and chorology of 51 selected fungal species. Draft, Leipzig (unpublished)
Rassi, P., Hyvärinen, E., Juslén, A. & Mannerkoski, I. (eds.) 2010: The 2010 Red List of Finnish Species. Ympäristöministeriö & Suomen ympäristökeskus, Helsinki. 685 p.