We currently have about 50 chickens, which is the most we've ever had. The oldest ones were born in 2011, and the youngest are still with their broody mom. With so many chickens at varying ages, it has become difficult to keep up with how old each hen is. We raise them for eggs, not as pets, so culling the older ones in order to maintain good egg production is necessary. We're trying to work out a system for managing this. So far it consists of a colored leg band assigned to each year, so we can tell that the green bands were born in 2011, red bands were born in 2012 and blue bands in 2013. We also started segregating each hen for a day or two to determine whether she is laying. Once she lays an egg, she gets her colored band (based on year of birth), and if she doesn't lay for a couple of days, she'll get a white band to show that she may not be laying. We have quite a bit of molting going on right now, so I won't give up on the non-layers for at least another month. What's your method for keeping up with who has gotten too old or has stopped laying?