500,000ha rough grazing at risk from soft rush infestation

Livestock farmers in marginal upland areas could vastly improve grassland productivity by treating land infested with soft rushes, delivering returns of 10.5:1.

Soft rush is a pernicious perennial plant spread by creeping rhizomes in the soil.

It is estimated that half-a-million hectares of the UK’s 5.18m hectares of rough grazing is in-bye pasture that is at risk from soft rush, with every 10% of cover reducing grass growth in equal amounts.

This in-bye pasture has a potential grass yield of 7-10t DM/ha (2.8-4t DM/acre) and offers farmers the opportunity to increase production sustainably in these areas by applying herbicide to kill the plant, independent grassland consultant George Fisher explains.

See also: Guide to controlling soft rush

Studies at Greenmount College in Northern Ireland proved weed wiping with glyphosate is highly effective at reducing soft rush from 81% to 21%.

Dr Fisher said those farmers set to benefit most are those in lesser favoured areas (LFAs) with in-bye grazing that can be more easily treated than hill ground.

According to Dr Fisher, every single application that reduces rush cover from 40% to 10% – a 75% control rate – will produce an extra 2t DM of grass/ha (0.85t DM/acre), delivering a return of between 4.0:1 and 10.5:1, depending on the situation (see table).

George Fisher was speaking at a NuFarm press briefing on soft rush control in Whitchurch on Friday (31 May).