It wasn't the first time that a tree was planted during a major championship:
"In the 1921 PGA Championship at Inwood Country Club, Walter Hagen played the seventeenth hole by driving down the parallel eighteenth fairway to give himself an advantage for his second shot. In his autobiography he explained why: "The green on the seventeenth was trapped on the short and left side, and almost at right angles to the line of play from the seventeenth fairway. If I played over onto the parallel eighteenth, I could open up the hole and come in from the right-hand side with my second shot." On the evening of the first day of the championship, while the golfers were gathered in the men's grill, several officials argued that a tree should be planted there to thwart such a strategy. Upon hearing this, Jack Mackie, the golf professional, and Morton Wild, a landscaper, uprooted a 15-foot weeping willow that they found in the woods next to the sixteenth fairway. They planted it to divide the two fairways. When he arrived on the tee the next day, Hagen quipped: "I never saw such fast-growing trees in my life."