Green poop- Because of eating leafy greens or nutrition problem?

I see a lot of green poop from my chickens. Not bright/fluorescent green, but sometimes drab "Army green" and sometimes a brighter grass-green.

As a group, they do seem to have fairly regular diarrhea (that's what set me on this poop research quest in the first place) and sometimes even the solid poop has an almost "grassy" consistency (like you'd see from a horse). About 3 weeks ago, two went in to the vet to see if he could help explain the diarrhea problem- he did a fecal to test for everything we could think of, but they were clear of worms, cocci, e coli, etc.

I have perused the link that shows the range of normal poop, and am not sure I see exactly what is typical color from my girls. I've freaked myself out by reading internet explanations (including on this site) that suggest poop this color is because chickens can't digest their food and are essentially starving to death and passing bile. I am hopeful that's not what's happening!

My girls get a lot of leafy greens (kale, lettuce, arugula) almost every day. They also free range, and seem to eat a lot of grass and are still grazing on what's left in my garden (and eating my still-growing brussels sprouts plants!!). I don't know if this is the case, but would eating this kind of diet lead to the greenish tint?

In terms of their diet, they eat an organic layer pellet at will, have a free choice supply of oyster shell mixed with poultry grit, and plenty of fresh water. Some days they also have a bowl of kitchen vegetable scraps (particularly days I know they will not get a lot of free range time). As a "bribe" for coming in from free ranging, they get ~1/2 cup of scratch- right now, it is primarily black oil sunflower seeds, cracked corn, and wheat, with a little bit of split green peas and pumpkin seeds mixed in.

Their health seems good, in the sense that they are all a healthy looking weight, eat with gusto, are very energetic and active. Two are older hens, the other 6 are pullets that have just hit point of lay.

Any thoughts?

 

Thanks ChickensAreSweet. This is not caecal poo- those happen on what seems like a normal scale to me. When I'm saying diarrhea, I do mean tail-up, watery puddle. I see 2-3 of these puddles every day, not always from the same chicken though. This is why I took them to the vet, because that just doesn't ever seem like a good thing in any animal. But all the fecal tests came back normal.