missed base
 

High school rules (red safety base).
B/R on way to first base after hitting ground ball to infielder, b/r steps on white portion of base, called safe. Can defense make a live ball appeal by stepping on first base with ball? Or must the defensive player tag her before she returns to first base?
Thanks

This would be a live ball appeal in either case. If the runner returned to the base before the appeal, you couldn't have a dead ball appeal.

A verbal appeal to the umpire is sufficient. Stepping on the base (which F3 was likely already doing) or tagging the runner helps to visualize the action for those not close to the play.

There has to be a play made, a defense attempt to get the BR out at first; for which half of the base to matter.
A live ball appeal for any missed base is by a fielder with the ball touching the base in an appeal manner or tagging the runner.
It can be a dead ball appeal if the runner continues and does not return before action has ended and time called. That would be vocal.