Bruising – the best way to deal with a pest like bracken

One of the things we're asked quite often is how we stop the spread of bracken on the Common. The first thing to say is that it's not a quick or easy job. Pteridium aquilinum, to give it its botanical name, is a common sight all over the island. It regrows each spring from underground stems and, if left unmanaged, can form dense colonies and destroy the bio-diverse turf of the Common, which has developed after years of being grazed.

In spring, new stems emerge from the rhizomes and these are often referred to as croziers or fiddleheads, because they are curled at the tip. Stems produce many triangular fronds (divided leaves) that are individually typical of a fern. With favourable growing conditions, stems can exceed 1.5m (5ft) in height by the end of summer. In autumn they turn reddish-brown before dying back to ground level.

How do we cope with that? Rather than use polluting herbicides, our favoured method is by bruising or damaging fronds by crushing them with a special "bracken bruiser" roller while shoots are still young and tender. This has to be repeated a few times during the summer as stems grow back to weaken the plant. Eradication using this method may take several years, and is labour-intensive, but it can be used to clear large areas of bracken on the Common without the use of chemicals.