Twenty-five parcels of land with oil-polluted soil were cultivated with different crop plants according to a statistical design (including landfarming). Over three growing seasons, the degradation of petroleum hydrocarbons (including polycyclic aromatic hydrocarbons) in the soil was analyzed. The rate of degradation became significant with the second growing season. Degradation in fields cultivated with corn, sorghum, and triticale was distinctly better than in fields with clover and alfalfa. Uptake of hydrocarbons by the plants was negligible compared to the amount degraded: hydrocarbon degradation is primarily the work of soil bacteria, but the plants decisively influence their growth and working conditions. At similar rates of hydrocarbon degradation, phytoremediation has a number of advantages over landfarming.
