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Dr Doug Edmeades

MSc (Hons), PhD, Dip Mgt, ONZM

Managing Director | Nationwide

Dr Doug Edmeades

Dr Edmeades commenced his science career in 1977 at MAF Ruakura, initially his research interests were on soil acidity and liming.

In 1985 he was awarded an ANZAC Fellowship and spent a year at the University of Queensland studying the effects of aluminium toxicity on pasture plants.

In 1988 he was appointed group leader (Soils and Fertilisers) at Ruakura and in 1991 became the National Science Program Leader (Soils and Fertiliser) in the newly formed AgResearch.

After 20 years in his role as a soil scientist at Ruakura Doug left institutional science in 1997 and established his own science consulting business, which has evolved into agKnowledge.

Doug’s vision for agKnowledge is clear; it’s purpose is to bring to the New Zealand farmer independent, objective, science-based solutions in the areas of fertilisers, soil fertility and pasture nutrition. He believes that the voice of science must be asserted against the pseudo-science that pervades society.

Doug contributes regularly to farming and science conferences and to the popular nationwide radio show “The Farming Show”. He is passionate about the role of science in society and believes that scientists have a responsibility to help laypeople understand the importance of science.

Dr. Edmeades has published 90 scientific papers, several books, booklets and pamphlets and countless popular articles.

Dr Robert McBride

MSc, PhD

Field representative | South Island

Dr Robert McBride comes from a working background on family beef, sheep, grape, and olive farms in California. After studying Forestry and Soil Science, he received a Ph D in soil science from North Carolina State University. Robert then worked in the fertiliser advisory sector specialising in organic farming, horticulture and cropping.

He first visited New Zealand as a tourist visiting farms across the North and South Island.  Robert fell in love with the rural character and agricultural-based economy of the South Island and immigrated to NZ in 2009.

A chance encounter with Dr Doug Edmeades at the Woodlands Research Farm, Southland, led to a job offer, and Robert now represents agKnowledge in the South Island.

Mr Vance Fulton


Field Representative | Bay of Plenty

Trained at the University of Waikato, Vance’s background is in soil conservation and environmental management. In this capacity he has worked for both Northland and Bay of Plenty Regional Councils and also had a stint as a Senior Soil Conservation Officer in Australia. He brings to the agKnowledge team complimentary skills which are important to ensure that we can offer our clients practical on-farm solutions to the environmental problems they need to deal with.

Mr Maurice Gray

Field Representative | East Coast

Based in Hastings, Maurice knows the North Island East Coast like the back of his hand. Most of the soil fertility and fertiliser trials conducted on the Coast, from Poverty Bay in the north to Wairarapa in the south, over the last 30 years, have been conducted by Maurice in his capacity of Senior Field Technician MAF and then AgResearch. He has accumulated a wealth of scientific, technical and practical knowledge and he knows what soil nutrient deficiencies look like in the field.

Mr Bob Longhurst

Dip Ag, Grad Dip. Appl.Sci.

Field Representative | Central North Island

Bob has followed the same career path as Doug and Maurice, having come up through MAF, MAFTech, then AgResearch. With a 40 year background in agricultural research that has covered soil fertility, farmer surveys, effluent management, wintering systems, nutrient budgeting and farm management plans he brings a wealth of experience to the agKnowledge team.

Mr Brian Devantier

NZCS, NZ Dip Sci, Grad Dip Rural Studies

Field Representative | Lower North Island

Based in Palmerston North, Brian has been involved in applied agricultural research for 40 years, predominantly in the lower North Island, initially with the DSIR, then AgResearch. With this depth of experience he has acquired a wealth of knowledge in farming systems, farm economics, soil fertility, nutrient budgeting and farm management plans. Brian has a particular interest in using this knowledge and experience to assist in the optimisation of farm enterprises.