CROSSROADS, N.M. (AP) — Carl Johnson and son Justin are third- and fourth-generation ranchers who for decades have battled oilfield companies that left a patchwork of barren earth where the men graze cattle in the high plains of New Mexico. Blunt and profane, they stroll across a 1 1/2-acre patch of sandy soil — lifeless, save for a scattering of stunted weeds.Five years ago, a broken pipe soaked the land with as much as 420,000 gallons of oilfield wastewater — a salty and potentially toxic drilling byproduct that can quickly turn fertile land into a dead zone.