Agency officials say the only fireworks allowed in the parks and forests are sparklers and snakes.
But they say rangers don't want to see them, either, because they're fire hazards.
They also say that fireworks can produce high concentrations of chemical particles that can lower local air quality for hours.
Citations can run as much as $200.
Anyone who starts a wildfire in Wisconsin is liable for fire-fighting costs as well as damages.
Parents of children who start fires by playing with fireworks also are liable for costs.