Conservationists and farmers are fighting to retain Asulox, a bracken control herbicide, that the EU is banning. It is one of the few effective chemicals for controlling bracken and the only one licensed for aerial spraying. Asulox kills bracken while leaving most other plants (including heather and food crops like spinach) unharmed. The ban has been brought in to protect food crops and loss of use against bracken in wilder areas seems to be a side effect. Although a temporary reprieve is in place, the ban will come into force at the end of 2012.
Bracken has very invasive rhizomes, is extremely difficult to control and is a habitat par excellence for the ticks that transmit Lyme disease to humans. It can be controlled by repeat cutting, but not on steep or rocky ground. Control is a real headache to farmers and countryside agencies. Intensive grazing by cattle can sometimes keep bracken down as they trample the young fronds but in the Scottish Highlands and in many national parks stock is not grazed at high density and sheep have a lesser footprint.
In the past bracken was harvested for animal and human bedding, for burning and for packing goods such as earthenware. These uses have died out and the harmful effects of bracken now predominate. It is thought to contribute to stomach cancers by contaminating water supplies and as a weed it is overpowering grass and heather in many places. Bracken grows beside and through many footpaths across the UK and many areas where walkers roam freely being unaware of the dangers posed.