Tsuga-conservation
Guides
Sasajiscymnus tsugae
hemlock woolly adelgid lady beetle
Sasajiscymnus tsugae is a small black lady beetle native to Japan that was introduced to eastern North America as a biological control agent against the invasive hemlock woolly adelgid (Adelges tsugae). First described in 1997 and released in the United States beginning in 1995, this predator has established populations in forest and urban environments. The species exhibits high host specificity, feeding primarily on three adelgid species. Field studies demonstrated 47–88% reduction in adelgid densities within five months of beetle introduction.