The agency's July farm survey says farmers can expect production to return to more normal levels for wheat, canola and corn for grain after records last year.
Total wheat production nationally is expected to drop 26.2 per cent from 2013 to 27.7 million tonnes, while the canola crop is expected to be down 22.6 per cent to 13.9 million tonnes.
Barley production is anticipated to drop 30 per cent to 7.2 million tonnes and oat production is expected to fall 32.1 per cent to 2.6 million tonnes.
Statistics Canada says that, at the time of the survey, farmers on the Prairies reported that excessive rain in late June was likely to affect what could be harvested.
One exception is soybean production which is anticipated to reach 5.9 million tonnes — surpassing the record 5.2 million tonnes of last year.