Salmonella is not all that common. There are other reasons or illnesses that could be making her sick. Green droppings can sometimes be from not eating enough food. Diarrhea can often be common in hot weather from drinking a lot of water, but also is common in coccidiosis, enteritis, or worms. Is she laying eggs, and how old is she? Reproductive disorders can cause lethargy and diarrhea as well. Can you pick her up and feel of her keel or breastbone to note any weight loss, and feel of her lower belly for any swelling or fullness. Check her crop a well, to see if it is empty, partially full, firm, or puffy. It should be empty first thing in the morning before she eats. If you can call your local vet and ask if you can bring in a couple of her fresh droppings, they can do a fecal float to look for worms and coccidiosis, and possibly a gram stain for bacteria. That could tell you if there is salmonella or not. Let us know if you need more help.