There was plenty of environmental stress on the 2010 crop, so I was not surprised when I was contacted in mid- June about an unhealthy field of canola. Mike is the owner of a 7,000-acre grain farm in southeastern Saskatchewan, and an excellent producer. He grows wheat, canola, barley, peas and flax.
Mike was concerned about one particular field he had planted with an herbicide-tolerant variety of canola — the field was sparsely populated and the plants themselves looked sick. He told me his other fields of canola seemed to be doing well, even taking into consideration the stress the recent rains were causing his plants. “This variety of canola has no vigour,” Mike said, clearly unhappy with its development so far.
When I arrived at the field, what struck me immediately was the appearance of lines, in some places the full length of the field, dividing the area into strips. The canola plants — just prior to cabbaging — showed various stages of maturity, and they looked very unhealthy and almost dead in some of the strips.
There were many factors to rule out in order to solve the problem of Mike’s sickly canola plants, from seed lot and variety issues to fertilizer application rate, machinery malfunction, as well as stress from the environment.
We began our investigation by checking if other farmers had reported poor germination or uneven maturity with this seed lot and variety. Since no other concerns had been registered, we ruled out these factors as causing the damage to Mike’s field. Environmental stress caused by heavy precipitation could also cause damage to the canola plants but would not present the regular and precise pattern we observed.
There would be a risk of seed burn with the over-application of fertilizer, perhaps due to the openers on the seeding tool. Mike’s fertilizer application rates were consistent with his other canola fields, his machinery was in good working order and the settings were correct during seeding. The damage to his plants could not be due to fertilizer rates or machinery malfunction. I thought the pattern in Mike’s field must be the key to the mystery.
To me, the lines in his field looked like a spray pattern, but we had eliminated fertilizer application as a possible source of the problem. When Mike mentioned he had used the recommended Group 10 herbicide on this field, I knew what was causing the strips of unhealthy, dying canola plants — I’d seen this issue a few times before.
Why does Mike have strips of sick, dying canola plants in his field? Send your diagnosis toGrainews, Box 9800, Winnipeg, Man., 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 aGrainewscap and a one-year subscription to the magazine. The best answer, along with the reasoning which solved the mystery, will appear in the next Crop Advisor’s Solution File.