>> For some years I have tested a system of requeening with ripe cells.
 
 
>       I wish I could trust this system. Others have told me about it
>but it didn't work well for us. Two years ago I marked 20 queens in three
>yards and gave each a ripe cell. Several days later I checked each hive
 
Vince,
What time of year did you try? I'm doing it at the time for swarming, or just
after. That's when the bees are prepared for a new queen in the hive. The
time for superseedure normally comes a few weeks later and some hives
have both queens side by side until they throw out the old queen.
 
I would not try spring or autumn without removing the old queen first. Also
with bad weather the success rate will go down.
 
regards  P-O