As a beekeeper I would ask that you try to use alternatives like Diatomaceous (sp?) Earth instead whenever possible, or at least make sure all of the excess dust is disposed of properly before putting the chickens out. The dust is too often misused/overused and deadly to our pollinators.
Thanks!
The Blue (Bl) gene acts as a diluter of black and is an incomplete dominant. There is also an Andalusian Blue modifier that adds the darker blue lacing. Sorry, I don't know the "code" for that.
Blue (B/Bl) x Blue (B/Bl) = 25% Splash (Bl/Bl), 25% Black (B/B) and 50% Blue (B/Bl)
Black (B/B) x...