You sprinkle a handful of crushed leaves and lichen into the air as you whisper a message of twenty-five words or less.  A wisp of wind picks up the dust and carries your message to a creature within range with which you are familiar.  If you speak the message in Druidic, the range increases to 1 mile.  If the target is more than 120 feet away, the message takes 1 minute to arrive.  In any case, the target must be outside to receive this message; otherwise, the spell fails.