28 November 1997

Weed threshold wisdom

BIG cuts in herbicide use are possible by basing spraying decisions on weed numbers. But no one is using the information, says Jim Orson of ADAS.

"There is a wealth of information out there. But I dont know of one farmer who uses weed thresholds as a basis for herbicide treatment." The technique would reduce the environmental impact of arable farming, yet maintain profits, he says.

Poor communication between researchers and farmers is one factor stifling uptake. And more site-specific work is needed.

Pesticide need must also be easy to assess a key difficulty is mapping weeds and treating them accordingly, though new precision farming technology will help.