Quote:
I'm kinda new to chicken genetics, but I don't think you will be getting olive eggs from that combination. Even with EEs laying a good blue or green color, the Barred Rocks are just plain brown eggs. So, you will probably get basic green eggs (you could also get just brown because an EE is a mix and does not carry 2 blue egg genes--it may pass the brown egg gene, giving 2 brown egg genes to the offspring).
Sorry to say, I'm doubtful that this combination will produce the dark "olive" green because you will need to cross them with a dark brown egg layer--like a Marans, Welsummer or Penedesenca. A chicken with a blue egg gene and a dark brown egg gene will produce the dark green olive color.
However, I could always be wrong--anybody else want to chime in here?