Abstract: Drifting willow catkins in air are a common phenomenon in late springs and often act as sentimental scenes in classical Chinese literature. By enjoying the popular line of the great poet Su Shi in the Northern Song dynasty, “the willow catkins on branches, blown fewer and fewer,” this article briefly analyzes the air viscous effects around the fluffs, the separated vortex ring structure above it, and the regulatory mechanism of fluff porosity. Based on these three skills, the flying mechanisms enable the lightweight porous fluff—such as the wind-pollinated seeds in nature—to remain aloft in air for a long distance. Then we extend the discussion to applications of such structures in miniature aerial vehicles.