Major League Baseball teams rub Lena Blackburne Baseball Rubbing Mud into their new balls to break them in.
For 70 years, the mud has come from a secret location along the Delaware River in New Jersey. The practice dates back to the "dead-ball" era of the early 1900s, says Jim Bintliff, owner of Lena Blackburne Baseball Rubbing Mud, named for the former baseball player who discovered the mud.
Bintliff says there were many wild pitches in that period, and umpires decided they had to take the factory gloss off the balls.
"They tried tobacco juice and shoe polish and dirt from under the bleachers, and found that while those things took the sheen off, they also damaged the leather and scratched the leather," he tells NPR's Melissa Block. "Lena experimented with this mud that he found in his fishing hole and found a concoction that the umpires liked, and we've been part of baseball ever since."
Although the dirt is an integral part of baseball, Bintliff says he still has to work a full-time job to support his family.
"Well, it's dirt," he says. "How much can you sell dirt for?"
An 8-ounce container costs $20, and 32 ounces will set you back $58. Usually, a Major League team can get through with one 32-ounce container a season, Bintliff says.
"I'm sure they spend more on mustard."