The first world war turned bracken into a serious menace. The exodus of agricultural workers from the land and with that, gone was the regular cutting back of this plant. Pteridium aquilinum
. Long out of print, 'Weeds and Aliens' by Sir Edward Salisbury, tells it straight: "one of the more noxious weeds of better drained grassland'.
Bracken invades with a vast network of starch-rich rhizomes. The stunning fact is that one acre of the plant will yield 40 tonnes in rhizome weight. Getting rid of it is not easy . Try cutting two or three times a year over several years. Better still plough the ground up and let pigs loose to eat the roots. Bracken cut before June is rich in potash and good for the compost heap.