Soil physicochemical analysis
We analysed the following soil physicochemical conditions from each sampling site before and from pots after the growth trial at CSBP Laboratories (Bibra Lake, Australia): phosphorus and potassium (Colwell 1965), sulphur (KCl 40) (Blair et al. 1991), organic carbon (Walkley & Armstrong 1934), nitrate, ammonium, electrical conductivity and pH (CaCl2).