SAVE our ash tips – orchids love them. One of the most unsightly industrial waste products, pulverised fuel ash from coal-burning power stations, is turning into an important habitat for rare British orchids. But the decline in coal-burning power stations and misguided efforts to “reclaim” the tips for farmland threaten this habitat, says Peter Shaw of the Roehampton Institute in London. Shaw has established an experimental ash tip in his college’s grounds.
Ash tips are initially extremely alkaline and sterile. But as the alkaline salts break down, the tip ceases to be toxic. Within two years, moss appears on the surface. Then grasses grow, and between eight and twenty years after the tip is abandoned, orchids appear in dense spectacular stands. Shaw’s favourite tips are the infilled Cheshunt gravel pits in the Lee Valley. “In places you can’t walk for orchids,” he says. Other much-loved sites are close to power stations in Wakefield, Carmarthen Bay, Wigan and Elland, near Halifax. Shaw estimates that there are around 400 hectares of undisturbed ash tips in Britain. “These tips are a declining conservation resource that should be protected,” he says.
