<blockquote><<Start collecting tree protectors now if you get the chance. My sheep would demolish a new willow stand in a heart beat. I reckon they could make a serious dent in an established one in a couple of days
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I'll be investing in a load soon... Any recommended types?>>
Sheep are amazingly tall when they stand on their back legs, so if you are protecting trees individually you really need to build a little pen around each one and make it maybe 5' tall. Probably best and simplest to fence off the whole willow area and have sheep grazing the rest.
Some sheep, I think Shropshires, don't eat trees, but most do