In a twist to the technique used to extract toxic metals from contaminated land, plants have indeed been made to harvest gold from the soil. Researchers at Massey University in New Zealand have provided what they believe is "the first evidence of significant gold uptake by any plant", according to a letter in the journal Nature. After treating the soil with ammonium thiocyanate, a chemical that makes gold soluble, they induced plants to accumulate gold from ore in the soil into their tissues.