[CameronS]

As the name suggests, i am looking for some plants that are hen/duck proof. The area is clay soil, on a slope and is partially shaded, i had thought of pampas grasses and mini conifers, but have never got around to testing the theory.

      

[Sharondp]

I have a pampas grass on  a slope in clay soil - so that will work! In fact - you can have mine - I need it moved to make room for the ducks! 

[plumseverywhere]

we had pampas grass at our old house and the chooks loved it for sunbathing, now they have a willow tree that they use for shade.

[valr]

I have heavy clay soil too. My chickens free range a  lot in the garden. They have not touched the clumps of geraniums - "proper" geraniums which are perennial, not pelargoniums which we usually refer to as geraniums (you know - the ones that stink IMHO!)
Weigela viburnum euonymous  lavatera and rhododendrons have also been ignored. Mimulas and verbascum have been demolished.