Hi I want to start with about 5 to 10 sheep,I've planted about 170 square meters of lucerne/alfalfa that I plan to dry for hay,I also plan on buying some tree lucerne trees for fodder,and I plan on letting the sheep graze in my yard 2 days a week, I just want to know if that is all that they need to eat,they will then only have the lucerne/alfalfa hay and tree lucerne in the winter? Thanks!