Researchers studied how different fruit trees absorb cadmium from soil. They planted apple, peach, plum, and pear trees in orchards with varying soil pH levels and cadmium levels. After 6-7 years, they found that apple trees absorbed very little cadmium, while pear trees accumulated high levels in all parts, including fruit. Peach and plum trees had moderate cadmium levels. Overall, pear trees showed the highest cadmium concentrations in roots, leaves, bark, wood, and fruit.