Occurrence and range of dicumarol concentrations in sweet clover

The dicumarol concentration in 272 cured sweet clover samples from 4 counties in North Dakota was determined. Dicumarol concentrations ranged from 0 to 164.7 mg/kg of sweet clover, with 64.6% of the 272 samples containing less than 10 mg/kg. Round bales were significantly (P less than 0.05) higher in dicumarol concentration (mean of 22.9 +/- 3.10 mg/kg) than were stacks or silage (means of 1.8 +/- -6.3 mg/kg and 0.6 +/- 2.1 mg/kg, respectively). The outer section of core samples taken from round bales contained significantly (P less than 0.0021) higher concentrations of dicumarol than did the inner section of the core, with means of 30.8 mg/kg and 16.6 mg/kg, respectively. A significant (P less than 0.0001) correlation existed between crude protein and dicumarol values (r = 0.44).