On Thursday 22 July Prof. Mike Wingfield, founding Director of FABI was joined by Dr Seonju Marincowitz, Dr Tuan Duong, Prof. Brenda Wingfield and MSc student Preston Shaw to undertake a suite of inoculations aimed at understanding the role of tree pathogens of importance to various FABI projects. These tests included fungi isolated from pines, euphorbias and aloes.  It was particularly interesting to conduct inoculations on tree aloes (Aloe dichotoma), which are dying of an unknown cause in various parts of South Africa.  Inoculations such as those conducted represent a fundamental step in providing a causal relationship between putative pathogens and the organisms (in this case plants) that they infect, so-called Koch’s rules of proof.  And in South Africa, with a huge diversity of native woody plants, one of the complexities in working with diseases is the challenge of obtaining and raising plants needed for inoculation.  Happily, in this case and with the help of the talented horticulturalist Jason Sampson of the University of Pretoria, the required plants were sourced.  Some weeks will now pass before the results of these tests begin to emerge. And hopefully they will provide some insights into various tree disease problems.