to beat or flog, especially for extracting the fibres from flax stalks; to scutch
1858, John Harland (editor), The House and Farm Accounts of the Shuttleworths of Gawthorpe Hall, in the County of Lancaster,The first operation in dressing flax is to swingle or beat it, in order to detach it from the harle or skimps.
To beat off the tops of (weeds) without pulling up the roots.