Recently ran across Jonathan Fraser Light's Cultural Encyclopedia of Baseball on Amazon. Found some interesting info on the role of the broom in baseball history. The National League was the first to deploy a whisk broom to clear dust and debris from homeplate beginning in the 1890's. Later,the AL introduced brooms although the long handled version. In 1904 Ban Johnson banned the long broom and went to the small version following an incident where a player tripped on a long handle broom running toward homeplate.
The most notorious incident involving a broom might have been in 2002 when Seattle Mariners catcher, Dan Wilson, had to borrow umpire John Shulock whisk broom to dust off home plate after Manager Lou Pinella piled dirt on home plate following a disputed call and tirade by "Sweet Lou".
From a fan perspective, the broom has become the symbol of a series sweep, the winning of all the games in a set of 2, 3 or 4 games. Typically, if a fan's favorite team wins the first two games of a three game series, a writer might lead their story with "get out the brooms, we're hoping for a sweep."
Reporting after the completion of a series sweeps might include a headline like: "Sweep Success", "Sweep Dreams" or "the "Sweep Smell of Success." Mercifully, I won't go.
Fans get involved with brooms by ribbing a rival team by going to an away game and taunting with cries of :"The City that Never Sweeps".
Team mascots may use a broom as a prop as an impending sweep nears.
An illustrious broom waver was The Boss, George Steinbrenner, who waved a broom following the New York Yankees second consecutive World Series Sweep in 1999.
The latest chapter of the brooms in baseball saga is that as a result of growing concerns about violence at games several MLB teams including the St. Louis Cardinals and Los Angeles Dodgers have banned brooms from their stadiums.