Chrysomyxa abietis is a macrocyclic rust fungus in the family Coleosporiaceae (Basidiomycota) that causes spruce needle rust disease on Norway spruce (Picea abies) and related conifers across Europe. The fungus completes its life cycle entirely on conifers, infecting current-year needles in spring through airborne urediniospores and aeciospores, causing yellowing, deformation, and premature needle drop. Infected spruce stands show characteristic orange-yellow stripe discoloration on young needles, affecting photosynthesis and tree vigor. The rust is widespread in central and northern Europe, including Belgium, Denmark, Hungary, Norway, Slovenia, and the broader boreal forest zone, wherever susceptible Picea hosts occur. Unlike many rust fungi, C. abietis does not require an alternate host (heteroecious cycle); it is autoecious, cycling between different spore stages on the same host genus. Heavy infections can weaken trees and increase their susceptibility to other stressors including bark beetles and drought. The fungus is not evaluated for conservation status by the IUCN, as it is classified as Not Evaluated. While typically a natural component of coniferous forest ecosystems, outbreaks may intensify under warmer, wetter springs that favor spore dispersal and infection.