I am retired since January 2016. Several data batches await still to be written and published. They deal among others with recent observations of Diplodia sapinea in Finland and the distribution of Heterobasidion butt rot in northern Finland.
Some years ago, together with several colleagues, I described a new needle pathogen Mycosphaerella pini in Finland (Müller et al. 2009). It causes red band needle blight on pines; in Finland on the Scots pine. We also determined the origin of this fungus by comparing its genetic diversity in Finland with that in Estonia and Central Europe (Drenkhan et al. 2013). Results showed, that this fungus must have existed in Finland for a long time. In fact Scots pine may be its primary host.
Climate warming, if continuing, can have profound effects on forest health. Thus several of my studies focused on the significance of temperature to the activity of pathogenic fungi. How do the pathogens adapt to a temperature rise and changes in precipitation? Are the pathogens more adaptive than their hosts? How important is temperature to fungal growth and proliferation? I have published two papers on this subject (Müller et al. 2014; Müller et al. 2015) and several other data batches await to be analysed and written down for publication on this topic.
For decades forest pathologists have been concerned about the spread of alien invasive forest pathogens. They can be extremely lethal to new hosts with which they do not share a common evolution history. Now new alien pathogens seem to appear at an exponentially increasing frequency in Europe. There are numerous sad stories from the past describing the decline of beautiful tree species - some to near extinction. One of the most famous examples here in Europe is that of the elm disease. The story about Dutch elm disease and similar other stories have been collected and published as supporting material of the so called Montesclaros declaration (Montesclaros declaration, see also separate page).