Availability of “bound” ¹⁴C-guazatine soil residues to the soybean plant (Glycine Max var. Shiratori) and the rice plant (Oryza sativa var. Nihonbare) was investigated under laboratory conditions, using three different soils (Kumagaya clay loam and Chiba loam under upland conditions, and Nagaoka clay loam under flooded conditions) which were pretreated with 5ppm (on dry weight basis) of ¹⁴C-guazatine-triacetate (TA) for 26 weeks to produce bound ¹⁴C-guazatine soil residues. Soybean plants grown in Kumagaya and Chiba upland soils containing bound ¹⁴C-guazatine residues were divided into various plant parts to determine their ¹⁴C-content. Four weeks after planting, ¹⁴C-concentrations expressed on a dry tissue weight basis in each plant parts were less than one-fifth of the ¹⁴C-concentration in the surrounding soil. Total ¹⁴C-recovery from the aerial tissues and from the whole plant tissues were only 0.08 and 0.12% of the applied radiocarbon to the soils, respectively. Quantity of the radiocarbon translocated into soybean seeds 9 weeks after planting was extremely small, and a large portion of this radiocarbon did not seem to be of the intact fungicide. These data demonstrated that the bound soil residues were unavailable to the soybean plant. Bound ¹⁴C-guazatine residues in Nagaoka flooded soil were also unavailable to the rice plant, which absorbed only 0.13% of the total radiocarbon applied to the soil during a period of 4 weeks. When the root of a rice seedling was treated with a nutrient solution containing 5ppm of ¹⁴C-guazatine-TA, an extremely high concentration of radiocarbon was detected from the root (2700ppm, 7 days) presumably due to adsorption of ¹⁴C-guazatine on the root. On the other hand, radiocarbon was poorly translocated into shoots (7ppm, 7days), suggesting guazatine to be an inherently low-systemic fungicide. On the basis of the data obtained, it seemed that plants grown in the soil containing bound guazatine residues are not significantly contaminated by root uptake and subsequent translocation.