The present results showed that the application of manure compost and sewage sludge could reduce available Cu and Zn concentrations in the Cu tailings. However, both the Cu and Zn contents in the shoots of vetiver and common reed tended to increase (Table 8). This may be due to the high contents of Cu that were initially present in both the manure compost and sewage sludge that was added to the Cu tailings, which also contained a high Cu content. Other researchers produced similar results. Cummingham et al. (1975) found that the shoots of corn and rye exhibited increases in Cu content with sewage application.