Chicken Throws Grass on Its Back

[Beau plus penny]

idk for me it justs means this is mine or sometimes broodies do this

 

[WingItRanch]

I've caught several of my hens in the nest box tossing a piece of straw or shavings on their back. It's probably a similar reasoning on why they like to lay in the nest with the most eggs. Safety in numbers and "camouflage."

Edited to add: I have seen both broody and non-broody hens do this.