Docks could pose bigger problems than usual for grassland farmers this spring, as the mild winter has encouraged early perennial weed growth, according to David Roberts, grassland agronomist for Dow AgroSciences.
“On many farms in the south, grass is growing which means the weeds are too – even in areas where the ground has been under water. Docks, with their extensive root systems are able to seek out aerated soil – so excessive wet conditions don’t really hold them back. They are in their “starting blocks” and ready to grow.”
Docks replace grass in a field – so a 10% infestation means 10% less silage in the clamp. So treating them with a translocated herbicide before first cut could help maximise grass yields, says Mr Roberts.
“The most effective time to try and control docks is early in the season before they gain a foothold,” advises Mr Roberts. “I would urge farmers to go and walk the fields now to see where seedling docks are emerging, and to note the size and numbers of established docks that have come through the mild winter. Farmers should then estimate the date of first cut, which could be up to three or four weeks earlier than last year.
“Then count back four weeks to find the ideal time to spray the docks. They should be at the right growth stage by then – presenting a rosette of leaves 150-200mm across or high and actively growing. This time period will allow the active ingredients to circulate within the plants and down in to the roots for thorough and effective control before the silage crop is harvested.”
Mr Roberts also suggests farmers try to minimise poaching of wet ground by turning stock out too early, to prevent more weed problems later on.
“Dock and chickweed seeds buried in soil will germinate and establish very quickly in bare areas in gateways, around troughs and in any wet areas of a field. The best way to keep perennial weeds out is to maintain a dense cover of productive grass.”