Do janitors have the power to stop a student from going somewhere? (i.e. on a field? )?

Today, me and my friends were throwing around a football (not jocks :P) and our school janitor confronted us and demanded that we leave the field, the reasoning behind this was that the field was "wet". It was a nice sunny day, birds were chirping, not a lot of dew was on the field, highly unnoticeable, so now im wondering (sry for the wait ): ) does he have the right to do so? he placed these pylons and then almost aulted us to get off of the field... correct me if i'm wrong but last time i heard, Janitors weren't teachers or supervisors...