Disputes over royalty payments for oil and natural gas drilling have involved several farmers in rural parts of the state. The Pennsylvania Farm Bureau is now calling on lawmakers to take action.

Farm Bureau President Carl Shaffer said some members have explained how they're losing money they say is legally theirs.

Jim Gore, a farmer in Bradford County, said he has documentation revealing about a 15% reduction in his overall royalty check in 2013 for so-called "post production costs."

"That hurts. It really does. I don't know how to go about trying to fight this and I've even looked through my lease and the addendums at the end of my lease say they can't do this."

Gore said Chesapeake Energy, the state's biggest driller, has taken out the most -- about 20%.

Armed with stories like Gore's, the Farm Bureau is pushing for an amendment to state law that would guarantee a minimum of 12.5% of the money companies made selling gas, no matter the post production costs.

"12.5 percent should be right at the well head. Right where it comes out of the ground. I have no more control over it after that. That's my whole point."

Chesapeake Energy declined to comment on the issue.

Republican Representative Garth Everett of Lycoming County has proposed legislation to guarantee lease holders 12.5% of royalties.

The measure is awaiting action in the House.