Teart land in Somerset: the farmers’ bulletin that blamed molybdenum in the grass
A bulletin from ICI’s Jealott’s Hill Research Station, usually dated 1940, told farmers what caused scouring on Somerset’s teart pastures and how to prevent it. Wiktionary’s entry for the farming word “teart” quotes an abstract of the bulletin as an early example of the word in use.
What the study did and found
The record is “The Teart Pastures of Somerset: The Cause of Teartness and its Prevention”, Bulletin No. 1 of Imperial Chemical Industries’ Jealott’s Hill Research Station, written by Ferguson, Watson and Lewis and usually dated 1940. The team also set out its findings in a 1938 letter to Nature and in 1943 papers in The Journal of Agricultural Science.
The letter cited about 8,100 ha (20,000 acres) of teart land in Somerset, where dairy cows scoured badly. The team traced the scouring of cattle and sheep to molybdenum in the herbage, at roughly 20–100 parts per million of dry matter, and found that daily copper sulphate prevented and cured it in their trials. Companion papers placed teart soils on neutral or alkaline Lower Lias ground and found clovers the strongest molybdenum absorbers.
Why it is cited
The one referring page recorded here is the Wiktionary entry “teart”, which links to the record from its first quotation for the adjective, a 1940 abstract by Green in Veterinary Bulletin.
That use broadly fits the work, since the quotation describes scouring land and molybdenum in the grass. The definition’s neutral-to-alkaline soil pH, however, rests on a second quotation, from Lewis’s separate 1943 soil paper.
The findings rest on 1930s and 1940s field and feeding work. The copper safety check followed just six cows, and even the 1938 letter was hedged, saying the evidence seemed to rule out bacteria, parasites, water or a particular herb.
Later research placed teartness inside a wider copper–molybdenum–sulphur problem: in the rumen, molybdenum and sulphur form thiomolybdates that bind copper.
The topic today
The national soil atlas of England and Wales still marks the Somerset teart area, with topsoil molybdenum of up to 37.5 mg/kg, and the 2018 EU copper regulation required a molybdenum warning on low-copper cattle feed.
For the current picture, see our explainer Teart Pastures in Somerset: Molybdenum and Cattle Scouring.