A (US:) colter / (British:) coulter (Latin 'culter' = 'knife') is a vertically mounted component of many ploughs that cuts an edge about 7 inches (18 cm) deep ahead of a plowshare.[1] Its most effective depth is determined by soil conditions.[2]
History edit
Its earliest design consisted of a knife-like blade.[3][1] In 2011 an early medieval coulter was excavated from a site in Kent, England.[4][5] Coulters using a flat rotating disc began being used c. 1900.[6][1] Its advantage was a smoothly cut bank, and it sliced plant debris to the width of the furrow.[2]
Results edit
In his 1854 book, Henry Stephens used dynamometer measurements to conclude that a plough without a coulter took about the same amount of force to pull but using a coulter resulted in a much cleaner result.[1] It softens the soil, allowing the plough to undercut the furrow made by the coulter.[1]
Jointer edit
A rolling coulter has an optional accessory called a jointer.[2] The jointer flips over a small part of the surface on top of the slice before the plowshare flips the main slice.[2] It ensures that all of the plant debris gets covered by the flipped slice.[2]
References edit
- ^ a b c d e Stephens, Henry (1854). The Book of the Farm Vol 1. W. Blackwood. pp. 271–272.
- ^ a b c d e Bacon, Charles Allen (1920). The Oliver plow book: a treatise on plows and plowing. Oliver Farm Equipment Company. pp. 160–162.
- ^ Our Steel Beam Rod Breakers from $6.50 to $7.70. 1896 Sears Roebuck & Co. catalog.
- ^ Thomas, Gabor; McDonnell, Gerry; Merkel, John; Marshall, Peter (2016). "Technology, ritual and Anglo-Saxon agriculture: the biography of a plough coulter from Lyminge, Kent". Antiquity. 90 (351): 742–758. doi:10.15184/aqy.2016.73. ISSN 0003-598X. S2CID 55156730.
- ^ "Anglo-Saxon 7th Century plough coulter found in Kent". BBC News. 2011-04-07. Retrieved 2023-01-13.
- ^ Our $9.75 Walking Plow. 1896 Sears Roebuck & Co. Catalog.