Crop Scene Investigation - 57: What happened to Wendel's winter wheat?

Sunday, November 8, 2015

by BERNARD TOBIN

April is a busy month for agronomist Paul Sullivan. That's when he and his crop scouting team start inspecting winter wheat fields as they spring to life and shake off winter's grip.

On one late April afternoon, Sullivan noticed an odd pattern as he scouted one of Wendel's winter wheat fields near Carp, east of Ottawa. In parts of the 115-acre field, every second row had a lower plant population, likely 50 per cent less.

"It was really odd, because the pattern only appeared in specific areas of the clay loam soil field," recalls Sullivan, who decided to gather some additional observations before talking with Wendel about what he had found.

The field was planted around mid-October the previous fall. Wendel had worked the ground following soybean harvest on Sullivan's recommendation. "In this area, we like to do pre-plant tillage on soy stubble going into wheat, because we tend to get better seeding depth consistency," notes Sullivan. This practice, however, can create challenges if the field gets rain before winter wheat planting.

As he walked through the field, Sullivan also noted that, in the problem areas, the soil appeared to be heavier and lumpier. It had been a wet fall and the agronomist was eager to ask Wendel about the condition of the field at planting.

When Sullivan caught up with Wendel the next day, he confirmed that planting conditions were less than ideal, but the farmer remembered being eager to wrap up the season and these last fields needed to get done.

Sullivan then turned his attention to Wendel's model 1890 John Deere air cart seed drill. He quickly noted that it was equipped with two gangs of disc openers and press wheels, and one set was ahead of the other in configuration. As the agronomist eyed the drill, he asked Wendel more questions about the previous October, when the wheat was planted.

Wendel said he noticed that the front disc openers were pulling up a bit of mud, which had been collecting on the back press wheels. This happened often, but the back press wheels always "cleaned off" as they travelled through drier areas of the field, he recalled.

Sullivan then took a closer look at the drill. He quickly determined that the wheat rows with lower populations would have been seeded by the back set of disc openers and closed with the back press wheels. That cinched it for Sullivan. He had figured out the mystery.

Do you know why every second row in Wendel's winter wheat had a lower population?

Send your solution to Better Farming at: rirwin@betterfarming.com or by fax to: 613-678-5993.  

Correct answers will be pooled and one winner will be drawn for a chance to win a Wireless Weather Station. The correct answer, along with the reasoning followed to reach it, will appear in the next issue of Better Farming. BF