Couldn't find it in AP Stylebook ...

[bigpern23]

Spring Training or spring training?

 

[Johnny Dangerously]

SPRING TRAINING if used as a dateline, but spring training for all other references.

 

[Cousin Jeffrey]

who uses spring training as a dateline? it's not a space station or the silk road through asia.

 

[write then drink]

SPRING TRAINING, Fla. -

very small place, so it has to take a state abbreviation

 

[MileHigh]

It's lower case.

 

[Johnny Dangerously]

who uses spring training as a dateline?

Only someone with a good sarcasm font should dare attempt it.