We mostly do pollard the willows, but the ones which split have done so to the ground so the only repair possible is coppice. I like the idea of sheep hay, but we give the whole branches to our sheep as they love the bark as well as the more delicate stems. Once the bark is stripped we can use the wood for stakes and firewood - we like our sheep to work for their keep
For the new trees, interestingly I found that
apparently Scottish hazels usually grow as multistems on their own, whereas in England they need to be coppiced in the first place before the multi stems appear. I'm not sure of how true this is. Of the hazels we've planted over the past 18 years, some are multistemmed and some on a single trunk. Not one has borne a nut though
The pollen is probably whisked away on the wind.
The new trees are well fenced from the sheep - ash and hazel, with willow on each side (not within the fence hence the sheep nibbling). It's very windy up here so for tall poles, esp the ash, coppicing seems safer, but some will be pollarded to improve the windbreak effect, which is what they were originally planted for.
We have a tiny piece of new mixed woodland planted up 8 years ago which now needs thinning, so we will be doing a mix of coppice, pollards and leaving the taller trees. We will also plant more wild flowers.
I grew up in Norfolk with my Dad's land backing onto ancient woodland which had been coppiced for 1000 years. Last night I searched to see if it is mentioned online, only to find it's well known and a nature reserve now. When I was a post war kid I had the whole place to myself and liked to practice getting lost and finding my way out again
I love woodland and am so enjoying the little bit we are making here.
https://www.google.co.uk/#q=foxley+wood+norfolk+imageshttp://en.wikipedia.org/wiki/Foxley_Wood