Quote from ppkitty »Silent clearing doesn't need to replace a colorless source though. It can replace a plains or a concealed courtyard. I would test it both ways but start with 4 and work my way down to find the right number.
You can certainly replace concealed courtyard by Silent Clearing but i woud hesitate to take out a basic land since we dont have any "real" fetch lands and Blood Moon hit us very badly. However, you are right to start from 4 and take some out to find the right number. I woud be interest to know how it ewnt down!