A study looked at how adding farmyard manure and lime to soil affects the availability of chromium to maize plants. They grew maize in soil with different levels of chromium and these amendments. The results showed that as the level of chromium increased, so did the amount found in the maize plants. Adding farmyard manure decreased the amount of chromium in the plants, while lime also had a similar effect. The amendments reduced the more easily available forms of chromium in the soil, but increased the less available forms. This suggests that these amendments can help decrease the amount of harmful chromium taken up by plants.