Our resident agronomist Peter “Wheat Pete” Johnson and OMAFRA cereals specialist Joanna Follings hatched a nifty plan a little while back to test out precision planting wheat using four different drills at Follings’ farm at Ayr, Ont.
(If you missed out on the seeding episode, you can find it here.)
“We’re already seeing some really cool stuff here today, and we’re seeing a lot of differences between treatments,” says Follings.
In this episode of the Wheat School, Johnson and Follings provide the first update on the trials including some preliminary results on the impact of down pressure and how that affects seeding depth between treatments; how residue management is impacting emergence and growth staging; and, the differences in row widths.
See the video below for all the details of Johnson and Follings’ on-farm trials as the crop emerges:
In a nutshell, down pressure was variable between some seeding units which affected emergence and plant staging. Some plants had one tiller, and in the same row other plants were still emerging.
What it really comes down to is planting depth, says Johnson, and variation in seeding depths requires different growing degree days. “The deeper the crop, the longer it takes to emerge,” says Follings. “It’s 50 growing degree days for every inch of seeding depth,” she adds. Furthermore, if you don’t hit moisture, you’ll run into trouble.
Residue management and spread pattern proved particularly important at the field trial, because it was seeded into corn residue. “What we’re finding here between the different technologies is that we don’t have enough down pressure to cut through that residue, we’re actually starting to see some of the seeds just start to germinate on the surface,” says Follings. That lack of seed to soil contact, and the variable seeding depth as a result of mismanaged residue will affect emergence and staging too.
The last factor the pair looked at, which is still a bit of a question mark, is row spacing, including 5 inch, 7.5 inch, and 10 inch rows. Whether there’s an advantage to switching to 5 inch row spacing, versus 7.5 inch or 10 inch, only time will tell.