Investigators are finding more and more pot on public land and they say you can be a huge help in catching the criminals growing it.

According to the Wisconsin Department of Justice, in 2007 agents seized just 859 marijuana plants on public land. In 2008, that number jumped to 9,823 plants. In 2009, agents confiscated 18,432 pot plants from public land.

David Spakowicz is the director of field operations for the Wisconsin Department of Justice Division of Criminal Investigation. He says the reason for the huge jump could be drug dealers turning to a new method of distribution. Spakowicz says traditionally most pot comes from Mexico and the Southwest, but he says growing it around the country cuts down on transportation and cuts out chances of getting caught on the highway.

Last fall, investigators cleaned up after a massive pot growing operation deep in the Tiffany Bottoms swamp in Buffalo County. This spring, the sheriff says they're going to do everything they can to make sure no more pot is planted on public land.

"Unfortunately they target small, rural counties," says Buffalo County Sheriff Mike Schmidtknecht.

Sheriff Schmidtknecht says his investigators are still working with the state crime lab on last year's case. This year, he says they'll watch 13,000 acre state wildlife area with a sharper eye. But, with a small department, he says it's important for all people using that land to do the same.

"The people who use the public hunting land for fishing or recreation purposes, they'll know if something is out of the ordinary or if something seems suspicious at all," Schmidtknecht says.

The sheriff says around Mother's Day weekend is prime planting time. But, he says if you come across something suspicious on state land, get out immediately and call law enforcement.

"If (they) have an organized unit growing, they have nothing to lose by protecting that much of a grow area,” Schmidtknecht says.

The DOJ says growing pot on public land isn't necessarily a new trend, but what has changed is the size of the crops they're planting. Spakowicz says it's gone from maybe a couple hundred plants at the most to the 10,000 plants they found in a single field near Shawano last year. He says 10,000 pot plants can be worth $10 million to $20 million.