micorrhiza with conifers as well as birch

[mollisia]

Hallo,

in another Thread Chris wrote the following remark, which interested my very much:

Originally Posted by Chris Yeates

similarly with mycorrhizal fungi, I remember many years ago being told by Roy Watling that birch is an honorary conifer the fungus in question in that instance was Lactarius rufus: I was convinced I was finding it in birch woods where there never had been conifers, but the only books I had at that time said always with conifers

Since some years in Germany we have the "problem" that here and there findings of Suillus collinitus/fluryi/roseobasis were reported which had grown under Betula. In the beginning I was refusing to believe that, because the Suillus species are know to be very restricted mycorrhizal partners of a very limited number of conifers each species. Most of them are confined either to Larix only or to Pinus only. In other countries there are species confined to other hosts, but always very strictly only one genus of host trees is reported.
So it sounded very unusual, that such a strcitly bound mycorrhizal species should make exceptions with Betula. But the reports got more, I think up to appr. 10 such findings are known now, were it was not possible to find a conifer (pine), not even a seedling. Some of these locations lay in private gardens, which are quite easy to check for possible micorrhizal partners.

In Russulaceae also some examples can be given for species, which grow with conifers and birch, such as Lactarius vietus or Russula aeruginea. But the Russulaceae are in most cases not so restricted to a certain genus of hosts as the Suilloideae and thus this is not as spectacular. But nevertheless it supports Roy Watlings remark.

We have other examples of host trees which can substitute one another, e.g. Corylus and Alnus (which are very narrow related) or Fagus and Abies.

But Betula substituting conifers is semething stranger and I would be very interested in learning if there are more examples of conifer mycorrhiza partners that have found exceptionally under Betula as well.

best regards,
Andreas