The ivy at Wrigley Field turns green about mid-May. Until then, the ivy is brown.
Wrigley Field wall
Ivy
1939 by Bill Veeck
Wrigley Field
It might be so that the batters don't lose their vision of the ball after it is thrown by the pitcher.
Not the poison kind.
Fish gelatin
No I'm sure soem kinds of ivy will be bad for it to eat like a poison ivy it wont eat that.
Airwaves is a chewing gum made by Wrigley Company
The stick used in many ivy plants to just to stable the ivy plants. You can use whatever kind of stick you have on hand.
Wrigley Field shares its name with the Wrigley Company, as the park was named for its then-owner, William Wrigley Jr., the CEO of the Wrigley Company.