This rapid PRA shows that Sirococcus tsugae, the causal agent of Sirococcus shoot blight on cedars and hemlocks, is a damaging fungal pathogen on Cedrus spp., with light to moderate damage seen on Tsuga spp. Native to the Pacific Northwest of North America, it has been introduced to Great Britain and is spreading, and has the potential to cause considerable damage to Cedrus spp. planted in parks, public spaces and individual’s gardens.