Andrew, a farmer from Southey, Sask., didn’t like the look of his canola crop late last August. “My crop looks off,” he told me over the phone. He asked me to visit his 2,600 acre operation to assess the situation.
“Why is my crop so far behind my neighbour’s?” he asked me when I arrived at his farm. “Could it be the variety? And why is my crop so short?”
Compared to the development of his neighbour’s crop, Andrew’s field was maturing slowly, the plants looked stunted and their leaves had a bluish tinge. The number and size of the plants’ pods were also reduced when compared with neighbouring crops.
I dug up a few of the plants to examine their roots. The roots were smaller than I would have expected of healthy, developmentally normal plants. This canola field was not ready to be cut; meanwhile, other crops in the area were being swathed. “The crop seemed to be slow for the entire growing season,” Andrew told me.
One by one we eliminated a number of potential sources of the damage to Andrew’s crop. The hybrid variety Andrew had seeded in the spring had a proven track record for its strong vigour, high yields and quality — I didn’t think the variety was the source of the problem. He’d also seeded at the same time as other farmers in the area, and at an ideal depth of three-quarters of an inch. Records indicated that no chemicals with the potential to cause herbicide injury had been applied to the field in the past three years. Since there was no evidence of feeding, we also ruled out insect damage.
Barley, peas and wheat had been grown in this field in the past, and the crops yielded 75 bushels per acre, 30 bu./ac., and 35 bu./ac. on average, respectively. Last spring, Andrew had side-banded 80-0-0-20 with three gallons per acre of seed-placed orthophosphate. However, I had a hunch that past soil test results for this field would reveal the true source of trouble.
What is causing Andrew’s canola plants to be stunted and their leaves to turn blue? Send your diagnosis to Grainews, Box 9800, Winnipeg, MB, R3C 3K7; email [email protected] or fax 204-944-5416 c/o Crop Advisor’s Casebook. Best suggestions will be pooled and one winner will be drawn for a chance to win a Grainews cap and a one-year subscription to the magazine. The answer, along with the reasoning which solved the mystery, will appear in the next Crop Advisor’s Solution File. †