One very effective herbicide is safe for corn, but soybeans are damaged even by the herbicide's residue, which remains in the soil more than a year after the herbicide is applied.

某种非常有效的除草剂对玉米来说是安全的，但即使是除草剂的残留物也会对大豆造成损害，该残留物在施用除草剂一年多后仍残留在土壤中。

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The herbicide was highly potent, and tests of soil samples confirmed that he had applied a liberal amount.

CNN: Auburn U. cutting down poisoned oaks