However, dandelions may be a special case, he says, since they seem perfectly suited to conditions in this area.

“I’ve only been in Wisconsin for two years, but I am amazed at how common dandelions are,” Renz says. “I have never lived in a place where the environmental conditions are just right for dandelions to explode like this in the spring.”

Dandelion seeds can drift on a breeze of just 4 miles per hour, and the plants can live for several years, so they can survive poor years and jump up the next spring.

The ecological role of weeds is to occupy new ground, and dandelions “are really good at invading sites,” Renz says. “Wherever they land, if there is bare ground, when it warms up, they will start germinating.”

In many years, dandelion seeds have already sprouted by February or March, he says.

The bad news is that an acre of pure dandelions can produce about one-quarter billion seeds, Renz says. The good news is that, “in the grand scheme of things, there are a lot worse plants than dandelions.”