9/10 Birds Prefer a Close Shave
It’s true, I have the photo to prove it.
Chickens prefer grass to be short and mowing it so in the area the birds are ranging provides access to the fresh new growth, better access to insects and grubs and also means the birds are less likely to ingest long coarse grass lengths which could lead to digestive problems such as impacted crop.
Other plus sides which your chickens might not be aware of is that short grass leaves few hiding places for the smaller almost microscopic pests such as parasitic worm eggs which don’t survive well when exposed to UV light rays. It also means the area is a little more exposed and less welcoming to larger predators so keeping some of the grass and scrub in check will helps number of counts.