I love BYC … yet another interesting and educational thread I am happy to have come across.
With the Caecals, those are also the ones that have a smell which can curl hair and toes and linger for the whole of the day?
If that is the case, then I think they can deposit them overnight .. I have had rude awakenings and been knocked back a few feet when opening the coop for a clean of the overnight deposits
I have not heard of oxalis so did some research .. interesting. It appears to be toxic to chickens but like many things, in large doses.
I think they can poop cecal at night, but it seems like mine do them more first thing in the morning after leaving the roost and at dusk before they roost. And yes, they are smelly!