August 1 rings in the new crop year and with it comes tightened grading tolerances of fusarium-infested grain. Nearly all western Canadian wheat classes are affected; the only exceptions are Western Red Winter wheat and General Purpose wheat, which are not subject to the restrictions until August 1, 2011. No change in fusarium levels will be made to the Canada Western Extra Strong wheat class.
The tougher restrictions are because of an increase in the virulence of fusarium and the resulting levels of deoxynivalenol (DON) that could be present. Over the years, due to a variety of factors, the relationship between fusarium-damaged kernels — the measurement used for grading “on the driveway” — and DON has changed, according to the Canadian Grain Commission.
As an example, as of August 1 the tolerances will be reduced as follows:
1) No. 2 CWRS 1.0 to 0.8 per cent 2) No. 3 CWRS 2.0 to 1.5 per cent 3) No. 4 CWRS 2.0 to 1.5 per cent There is no change for No. 1 CWRS at
0.25 per cent.