A former agricultural adviser, director of a west Norfolk experimental husbandry farm and enthusiastic orienteer, John Ward, has died peacefully at home aged 71.

In his eight years at the former ministry of agriculture's Terringtom EHF, near King's Lynn, practical research to improve the welfare of pigs, especially sows, was speedily implemented on farms and enabled loose housing of sows and finishing pigs to replace traditional systems.

John Thornton Ward, who was born in Essex, won a scholarship to Brentwood School. He studied at Writtle Agricultural College in his native county before embarking on a career in potato marketing in Lincolnshire. He gained a further qualification in farm management at Writtle and joined the ministry of agriculture's NAAS (national agricultural advisory service).

Sent to north Norfolk as a district officer, he impressed with his knowledge of root and cereal crops and was a regular at Holt and District Farmers' Club. For eight years from his home at Horsford, near Norwich, he covered an area towards the coast.

Promoted as senior adviser by the successor, Adas, he ran the ministry's regional office at Derby until it closed. In 1984, he wrote Oilseed Rape, a definitive text on the crop.

He returned to Norfolk becoming EHF director, where other research projects included stockless organic farming. Another included planting nine hectares (30 acres) of fast-growing poplars, which could absorb pig slurry to produce energy and boost lowland timber production.

When the EHF network was rationalised, Mr Ward, then 52, took early retirement in March 1994. He started an independent trials business at Sacrewell, near Peter-borough. A former chairman of Stoke Ferry Agricultural Society, he was also a committee member. He was a chairman of the East Anglian branch of the British Orienteering Association. He was chairman of the governors of Watlington School until his recent retirement. Married for 46 years, he is survived by Sally, and two sons, Joe and Peter, and two grandchildren.

A funeral service was held at Watlington Church on May 22 at 10.30am followed by cremation at Mintlyn Crematorium.

Michael Pollitt