14 November 2001
Dow launches thistle control star system

By Andrew Blake

A STAR rating system from Dow Agrosciences aims to help growers combat creeping thistle and prevent the weed developing resistance to key herbicides.

The main problem in deciding how to react to infestations is their patchiness, making overall spray treatment of light infestations uneconomic, says the firms Rene Pollak.

Creeping thistle has also developed resistance to some older herbicides like MCPA elsewhere in the world.

With only three modes of action available among UK thistle weed-killers, the full range of control strategies needs considering, he advises.

The star system, taking into account crop type, thistle frequency and location, cultural and chemical control, anti-resistance strategy and spray timing allows users to assess the threat and adopt appropriate tactics.