Timing is key when it comes to tackling weeds in newly reseeded pastures. Dock-infestations can seriously impact on both yield and quality of silage and grazing ground.
The post-emergence management of newly reseeded leys is key. It is recommended that around six weeks after the seed is sown, when the grass is at the two to the three-leaf stage, that weeds should be tackled.
Docks and chickweed
The two main target weeds are both docks and chickweed if present.
Tony Brennan - ruminant business manager Glanbia Ireland - said this is the most successful stage to control docks as after they establish a strong taproot, they are harder to eliminate.
“It is vitally important to control weeds when they are small as this guarantees total elimination of the weeds especially with regard to thistles and docks,” said Mr Brennan.
“If a dock establishes roots, say after 12 months, then it is much harder to kill this plant. That is why we need to target the spray six to eight weeks after reseeding.”
“Chickweed is another weed which can totally smother out grasses in newly sown leys which will, in turn, create bare patches which will allow other perennial weeds such as docks and thistles to grow in their place,” he added.
Mr Brennan said Esteem is a powerful three-way mix of herbicides, as it includes 80 g/L of Clopyralid, 100 g/L of Fluroxypyr and 2.5 g/L of Florasulam.
It is most effective in the control of broadleaved dock, curled dock, creeping thistle, spear thistle, chickweed, creeping and meadow buttercups.
He pointed out that severe infestations of docks and reduce dry matter yield. Mr Brennan said they can also damage the protective wrap in baled silage.
Strong levels of chickweed have been noted in silage ground this year following last year’s dry weather.
He said best controls are gained when applied on newly sown leys or reseeds with an application rate of 1.0 L/Ha around six to eight weeks after sowing.
However, he pointed out it can also be used on established grassland with an application rate of 2.0L/Ha.
Stock must be left off of the targeted area for a minimum of seven days and any off-takes of silage must be left ideally for 28 days but a minimum of 21 days, he explained.
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Video produced and edited by TF Media