we've been usng an orange plastic bag of sheep nuts (they don't like sugar beet shreds) - shaked, carried high and OH always shouts out 'yum yums' (who am I to argue?)
They do come down the hill for the treat but no closer than 20yds and wait 'til we've gone.
Treat time is 4.30 and they're waiting.
On a good day we have managed to tempt them (lay a trail) into the smaller field adjoining which is where I can catch them.
Oh, and there's a stand of willow in their field anyway.