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The multidisciplinary ‘Phyto-threats’ project was initiated in 2016 to address the increasing risks to UK forest and woodland ecosystems from trade-disseminated Phytophthora. A major component of this project was to examine the risk of Phytophthora spread through nursery and trade practices. Close to 4000 water and root samples were collected from plant nurseries located across the UK over a three-year period. Approximately half of the samples tested positive for Phytophthora DNA using a metabarcoding approach with 63 Phytophthora species identified across nurseries, including quarantine-regulated pathogens and species not previously reported in the UK. Phytophthora diversity within nurseries was linked to high-risk management practices such as use of open rather than closed water sources. Analyses of global Phytophthora risks identified biological traits and trade pathways that explained global spread and host range, and which may be of value for horizon-scanning. Phytophthoras having a higher oospore wall index and faster growth rates had wider host ranges, whereas cold-tolerant species had broader geographic and latitudinal ranges. Annual workshops revealed how stakeholder and sector ‘appetite’ for nursery accreditation increased over three years, although an exploratory cost-benefit analysis indicated that the predicted benefits of introducing best practice expected by nurseries outweigh their costs only when a wider range of pests and diseases (for example, Xylella) is considered. However, scenario analyses demonstrated the significant potential carbon costs to society from the introduction and spread of a new tree-infecting Phytophthora: Thus, the overall net benefit to society from nurseries adopting best practice could be substantial.

Mike Dunn's grandfather was one of the original Fishing Club founders, as a D.C. Mason. Although the Dunn family bought property across the access road due to having six members and needing more space, the interaction with the club lasted three generations. Mike remembers growing up hanging around with his generation of fishing club kids during the long summers spent with his grandmother at the Shady Side cottage. He also describes his father taking ownership of the cottage, and finally his taking it over with the hope that his children would keep it going.

Shotgun sequencing of microbial communities is a promising means for delving into community function and interactions, population structure and dynamics, and bypassing the cultivation bottleneck in microbiology. However, this approach is mostly blind to low‐abundance species as it effectively samples only the dominant populations in a community. It also faces a number of technical challenges such as the assembly and separation of individual genomes from a mixture of genomic fragments compounded by sampling unevenness and data scalability. Despite these limitations, environmental shotgun sequencing should rapidly advance the fields of microbial ecology and evolution.

We describe pair hidden Markov models, with an emphasis on their relationship to evolutionary models and hidden Markov models. We then explain the statistical interpretation of alignment with pair hidden Markov models, and highlight connections to the Needleman–Wunsch algorithm and other dynamic programming–based alignment algorithms.