A hay knife is an agricultural hand tool: a long-bladed knife which may have large rounded serrations on the edge, or a smooth edge used for sawing off sections at the end of a stack or compact pile of hay or silage.
In the south of England hay knives may have smooth edges.
[citation needed] Hay knives are needed as loose hay or silage becomes compacted within a stack: to remove it a hay knife is used to make a vertical cut so that sections can be removed easily as the intertwined stalks are cut.
The offset handle allows the user to work down a face.
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