TULSA, Okla. (AP) -- A federal magistrate gave Oklahoma permission Wednesday to take samples of soil, water, waste and runoff from chicken farms as part of its water pollution lawsuit against Arkansas poultry companies.

The ruling by U.S. Magistrate Sam Joyner was in response to motions filed by the companies to prevent the sampling.

"We will be in the field as soon as we can," Attorney General Drew Edmondson said. "The corporate polluters have successfully delayed the sampling for a few months but they cannot delay forever."

Last month, Oklahoma Attorney General Drew Edmondson issued about two dozen subpoenas requiring landowners to allow investigators to collect the samples. Many of the landowners raise chickens for companies Edmondson has sued.

Edmondson has sued 14 poultry companies, alleging that chicken litter applied as fertilizer by Oklahoma farmers working for Arkansas companies is polluting watersheds.