LINCOLN, Neb. (AP) — The mayor of Nebraska's capital city has complained to Kansas officials about smoke from its agricultural burning that sometimes makes it unhealthy to breathe in some parts of Nebraska.

The Lincoln-Lancaster County Health Department issued health warnings about the smoke three times earlier this month.

Officials have said the smoke originates mostly in the Flint Hills area of Kansas, where farmers and ranchers burn grassland yearly to stave off invasive species, preserve pasture, improve cattle forage and limit fuel for wildfires.

Lincoln Mayor Chris Beutler (BYTE'-lur) su...