Hi Freddycat21
20ac - Think of how you might beat a grain crop
27ac - Definition is last four words - wordplay a partial anagram (but Mark leaves) plus ?R
60ac - my last one, and I too am stuck. Several words fit S?S?E? but none seem to tie in with whatever the definition is - Ends? Ends of branches? the way? block the way?
Any clues from others welcome