Crowd control in OSR
As the AHDB outlines, the relationship between yield loss and volunteer numbers is linear, with “this relationship…exacerbated by a delay in sowing and by thin or less vigorous crops. For a crop sown on 26 August, 100 volunteers/m² can give a 5% yield loss but for crops sown on 9 September this is reduced to only 10 volunteers/m².”
Lutman, 1991. New approaches to weed control in oilseed rape. HGCA, Project Report No. 530
When it comes to controlling unruly volunteers in oilseed rape, there’s only one thing for it… propaquizafop.
Propaquizafop – available as FALCON (100g/l propaquizafop) – is the ideal herbicide for the control of cereal volunteers in oilseed rape. It is also effective against ryegrass, common couch and sterile broom and, as well as being licensed for used in OSR, can also be used to protect a wide selection of legumes and vegetables.
At its full application label rate (1.5l/ha) FALCON effectively checks annual meadow grass up to the weed’s three-leaf stage, with this higher rate giving growers the option to provide an extended period of weed control until a subsequent propyzamide application is made later in the season.
In oilseed rape, FALCON can be applied at any time prior to the crop’s flower buds becoming visible and 90 days before harvest: when used to control cereal volunteers prior to tillering it should be used at 0.5l/ha, with this rate increasing to 0.75-1.0l/ha if tillering has already taken place and the weed has become well established.
FALCON can also contribute to the control of black-grass as part of herbicide resistance management strategy involving mixtures and sequences with herbicides of alternative modes of action.
FALCON® (also marketed as SHOGUN®) is a foliar acting selective herbicide with systemic activity on a wide range of grass weeds and volunteer cereals. It can be used in oilseed rape, potatoes, beet and a wide range of other broad-leaved crops.
Active ingredient: 100 g/l propaquizafop