The importance of sound advice and research to tackle grass-weed issues

UK - July 12, 2010



Casting an eye around crops at harvest time this year can only reinforce the difficulties that growers have had containing and controlling grass-weeds such as black-grass and wild-oats.  It will also reinforce the ever-increasing need for the best advice from agronomists, the need to get the most from the remaining herbicide tools and an ever increasing focus on the use of propyzamide in oilseed rape to tackle these major weed challenges.

"Despite our current oilseed rape crop experiencing some very difficult growing conditions; a dry autumn, followed by a very cold and prolonged winter and then a cold, dry spring, and few spraying opportunities, propyzamide was used over a record area as many growers recognized the need to use the oilseed rape crop to lead the relentless battle against black grass." says Robin Bentley, Product Manager for Dow AgroSciences.

"With less than expected levels of black-grass control, even from the best of herbicides in wheat, plus escalating levels of weed resistance, we need more effective ways of achieving robust control of this difficult weed across the farm's rotation.  The use of Kerb Flo in winter oilseed rape and winter beans in a programme can be exceptionally effective in reducing the spread of this weed and, with top-class advice, this herbicide can offer exceptional levels of weed control.  The performance of propyzamide in autumn 2009 has been excellent and it is seen as an effective and valued tool to control grass-weeds," he says.
"What is certain this year is that the role of the agronomist, with his or her level of knowledge and practical expertise, will be heightened by the weed challenge that faces many farmers this season.  As a manufacturer we too have played our part and have spent considerable resources this year and over the years to investigate best practise and how to mimimise the risk of water pollution," says Robin.

Robin explains that Dow AgroSciences has conducted wide-ranging research work on the pathways by which propyzamide can move from treated land into water courses and how different cultivation regimes and the use of buffer strips affect this movement.  "We are making some conclusions of the work now and hope to be able to service advisers with new advice arising from these detailed investigations at Cocklepark over the coming month.  Three different establishment techniques: min-till, partial inversion and full inversion plus three different width buffer strips, have been profiled and replicated on the experiment.  Early indicators suggest that establishment technique can have a substantive effect on reducing the movement into water with min-till showing the best effect. Coupled with the earlier work conducted at the Allerton Project which looked at the relative difference of drain flow and surface run off as contamination pathways and the impact of buffer strips in effecting the latter, we hope we can derive some field level management guidance for advisers to particularly address high risk situations and limit the movement of propyzamide in water."

"It is vital that everyone plays their part in keeping this valuable herbicide out of water, so that its future is secure and that it can continued to be used as an essential tool in the armoury against black-grass and other grass-weeds."

"Kerb Flo is a highly effective residual grass and broad-leaved weed herbicide, but requires good advice from advisors in order to get the best out of it.  For example maximum weed control requires low soil temperatures.  This gives longer persistence and better weed control throughout the weed germination period.  Good levels of soil moisture are also needed to help distribute the herbicide evenly in the top few cms of the soil, from where the weeds usually germinate.  If application conditions are right farmers can expect black-grass control in the high 90's, a level that very few herbicides can attain now-a-days even under optimum conditions of use," says Robin Bentley.

"Regular reports on soil temperatures and moisture deficits as well as on product compatibilities will be available.  There will be timely technical updates, advice on Specific-Off-Label Approvals as well as online topical support via the DAS web site, www.dowagro.com/uk."

"By using Kerb Flo, advisors and growers will be supporting, and benefiting, from an extensive and on-going Stewardship Programme.  Unlike the generic companies, we are actively involved in Environmental Stewardship, investing substantial sums on trials on how best to keep Kerb Flo out of water."

Robin also points out that Kerb Flo is a high quality formulation with a unique brown colour -distinct from the white generic material.  "Our product is of very high specification, easily tank-mixable and has a wide range of SOLAs, certainly not the case for many other generic propyzamides.  Some generic propyzamide materials have had severe mixing problems, not what you want in a busy spraying season.  We are also working on a new formulation which has less propensity to leach and are developing a new active to partner with propyzamide to extend the weed offer in autumn 2011."