(AP) – Kansas City police have recovered considerably more marijuana this year than they did last year.

Police say they found about 850,000 pounds of pot in Kansas City this year, which is a nearly 4,000 percent increase from 2012.

The Kansas City Star reports most of the increase stems from the August discovery of two huge fields of what’s known as “ditch weed,” a type of marijuana that’s very low in THC, the active ingredient in marijuana.

Police also say some of the increase is because of high-grade marijuana coming to Kansas City from the West Coast. Sgt. Chris Ceseña says some of the supply is being generated by people getting into the legal medical marijuana industry in states that have voted to legalize small amounts of medical marijuana.