Biology, Detection, and Management of Lecanosticta acicola : Emerging Challenges for the Management of Brown Spot Needle Blight in Pine Forests

ABSTRACT Brown spot needle blight (BSNB), caused by the fungus Lecanosticta acicola , is a widely distributed foliar disease of pines that causes needle necrosis, premature defoliation, and growth loss in both natural forests and commercial plantations. Although L. acicola has been reported from more than 50 pine species worldwide, recent large‐scale outbreaks on native loblolly ( Pinus taeda ) and eastern white pine ( P. strobus ) in North America highlight emerging management challenges within the pathogen's presumed native range. Here, we synthesise current knowledge of L. acicola taxonomy, biology, pathogenicity, and global distribution, with particular emphasis on how recent North American epidemics fit into the broader invasion history and what they reveal about host–pathogen–environment interactions. We review how taxonomic instability and cryptic diversity complicate species delimitation and surveillance, and evaluate diagnostic and monitoring approaches spanning field sampling, microscopy, culture‐based isolation, spore trapping, species‐specific PCR and LAMP assays, and the emerging roles of environmental DNA and remote sensing. We then assess control and management options, including fungicides where permitted, silvicultural and hygiene practices, and resistance breeding in pine improvement programs, and place these in the context of projected climate‐driven range expansion and ecosystem impacts. Finally, we highlight key research and policy priorities, including coordinated long‐term monitoring, genomics‐informed resistance screening, and international collaboration and data standards, that are needed to support integrated management strategies and mitigate the growing threat of BSNB to pine‐dominated forests in North America and globally.