An energy dispersive X-ray fluorescence method for trace element analysis in plants (leaves and roots) is presented. The method is characterized by the use of a secondary target excitation, thin specimen, and microwave acid digestion. The accuracy is about 10% and the sensitivity is in the range 10-50 ng/cm2. The analysis time (from dry sample to concentration data) is about 4 x 10(3) s. The effects of Cr in sewage sludge on barley seedling growth is presented.