The true dry rot fungus (Serpula lacrymans) as a wound parasite of living Norway spruce (Picea abies) in the Czech Republic
J Bech-Andersen, S A Elborne, J Andreasson, J Ch Sterler
Some late 19th century Central European mycologist reported finds of the true dry rot fungus (Serpula lacrymans) from nature. They even suggested that it could be a parasite of living trees. However examination of herbarium material has shown that the species they found was thin-fleshed dry rot (Serpula himantioides) rather than Serpula lacrymans. In 1992 the Czech mycologist Kotlaba reported finds of Serpula lacrymans from twelve localities in the Czech Republic. In most finds fruitbodies were growing at the base of living Norway spruce (Picea abies), and he therefore suspected it to be parasitic. In September 1998 some of these localities were visited by Hussvamp Laboratoriet but in vain. In October 2000 four of the localities were revisited by the authors from Hussvamp Laboratoriet. In the first locality a forest west of Plzen the search was succesfull. About a dozen well-developed fruitbodies were found on the exposed roots of a spruce stump. The living tree had evidently been infected by dry rot through its roots, and later tipped over during a storm, and finally the trunk had been cut off leaving the stump. Such a log is a potential source of infection into houses. An other still standing and live spruce a few metres away was apparently infected in a wound near the ground. Soil, wood and mycelium samples taken from the find are currently being analysed for their content of calcium, iron and other minerals. The meteorological data, especially temperature and snowcover are also being analysed. These data will be compared with the previous finds of Serpula lacrymans from nature in the Himalayas and Northern California. Cultures from the find are being analysed for molecular data and Trichoderma species are isolated from the soil samples as potential agents of biological control of dry rot attack in houses.