Residues in herbage and silage and feeding experiments following the use of diquat as a desiccant

Diquat has been used as a desiccant in silage production. Results of analyses show that diquat disappears rapidly from sprayed herbage so that residues in the silage are at an acceptably low level. No toxic symptoms were observed in long‐term experiments feeding the silage to sheep and cattle and no residues of diquat could be detected in the animal tissues or milk. Of the diquat ingested by sheep 40‐45% is excreted and less than 10% of this is excreted in the urine. The large proportion of diquat unaccounted for may be degraded in the digestive system of the animal.