Regarding the first meaning; when the crop had been cut the reapers gathered and tied it, stem downwards, into large bundles, sheaves, or stooks, and left the bundles standing in rows of golden yellow pyramids across the field.

They're called stooks, and a field was done this way this summer outside a Northamptonshire village called Isham (which has a very nice pub called The Monk and Minstrel, of which I am an habitue). It was done because the straw was going to be used for - goddammit - thatching. I had a drink with the gang who did the deed, and they done told me so. They are sheavers, and one of them is also a thatcher. So, sheaving comes full circle ...