(CBS News) LOUISVILLE, Ky. - America's national pastime is all about tradition. But one of Major League Baseball's most cherished features is now threatened. That can be blamed on a foreign invasion.
Professional baseball players have preferred bats made of ash wood for over a hundred years, giving the game a sound all its own.
Bobby Hillerich's family has made Louisville Slugger baseball bats for five generations.
"Ash wood has got a wonderful weight-to-strength ratio," said Hillerich. "It might not be the most dense wood, but it gives a wonderful sweet spot and great sound."
But that sound is in jeopardy because of the emerald ash borer. The half-inch long insects kill every tree they infest within two years by tunneling into the bark and starving it to death.
"We have been greatly concerned about it," said Hillerich. "There is absolutely no doubt about it."
Over 50 million ash trees in the U.S. have died since the beetle arrived here in 2002. They came aboard Asian cargo ships and are now found in 20 states, including Pennsylvania, where Louisville Slugger buys the wood for the bats they make.
Asked if he is stockpiling the woods and if people are cutting the trees down in larger numbers before they actually get infested, Hillerich responded: "I won't call it a panic, but we've have seen that situation where landowners are trying to get their value out of the timber because it's still a very expensive tree, and if it's not infested it's worth a lot of money."
The beetle has no natural predator. Hillerich says pesticide treatments are too costly at $300 per tree. His company harvests 100,000 trees a year.
"Not only are we looking at other places to get our ash trees," said Hillerich, "but maple being almost 50 percent of the pro market, we're seeing that start to trickle into retail. I think there will be alternatives. I hope that we never have to get that way."
Baseball has endured big changes before, but never because of something so small.