Rotation isn't only about alternating crops and fields

Wednesday, July 05, 2017

After challenging conditions for last year’s harvest and this spring’s seeding, most growers are focusing on this year’s crop rather than looking ahead to next spring. But what they’re seeing in the field this year can provide valuable information for planning next year’s crop.

“Once they have planted and sprayed and confirmed the weed problems in their field, their current crop mix and herbicide-tolerance system, then they have the information they need to start thinking about options for next year,” says Scott Anderson, manager of agronomic services for Nutrien Ag Solutions (Canada) in northwest Saskatchewan.

Keith Gabert, a Canola Council of Canada agronomy specialist in central Alberta, says careful scouting and recordkeeping can really help variety selection for next year.

“A grower should be able to say things like ‘The last time this field was in canola I didn’t see any blackleg and had cut 10 stems in three locations in that field.’ Or ‘A couple drowned-out sick-looking spots turned out not to be clubroot — but I found a lot of plants with sclerotinia there.'”

Gabert’s advice is that one size does not fit all. “All of the value-added traits are important, but knowing the disease challenges present on your farm will help you select varieties that have traits that will reduce risk, and increase yield in your fields by focusing on traits that bring value to your operation.”


Field trials help companies showcase their varieties and demonstrate how they will perform in the local area or across the Prairies.

“The best way to decide (on variety) is by participating in a few summer plot tours, knowing what your neighbours are also evaluating for varieties and trying more than one variety on your farm each year,” says Gabert. He adds that looking at data from trials in the local area will help evaluate the varieties that succeed year after year in the region.

Anderson agrees. “I would like to see more people taking advantage of plot tours in their local area — the best way to learn about a variety is to see it and stand with it in the field. The nice thing is that they are available across the Prairies and give an accurate look at how a certain variety will do in that area. People should be pulling over and walking out in the field.”

He adds that these trials are important for both growers and staff to see what is available and how it is performing.

“Collecting all the data possible, including information at field trials, are the best tools growers can have to make strong decisions for the coming year,” says Anderson.

Tours of field trials are offered by many seed and input companies across the Prairies. One of the largest will be Ag In Motion (AIM) in Saskatoon in July.

“These are producer-managed trials. The information comes straight from our farmers, in their fields,” says Jade Delaurier, manager of agronomic services for Nutrien Ag Solutions (Canada) in east Saskatchewan. “Nutrien Ag Solutions (Canada) also includes experimental varieties in field scale trials so they are being tested in real-life application.”


Knowing the issues growers face in their own fields will shorten their list and allow them to pinpoint the genetics they are looking for. Traits to identify in field trials include height, standability, maturity, disease resistance, yield and harvest management.

Storyboards will be available at many trials and will include information such as disease or pest problems in the field, and how and when they have been treated.

“The trials are taken very seriously,” says Delaurier, adding that there are protocols in place such as supplying booties to prevent cross-contamination between fields, and information should also be available online.

Timing of the plot visits can also be important. “I want growers to look at the overall agronomics of the variety beyond yield,” says Anderson. “It is great to get out and look at the trials in the fall so it is possible to see any issues with lodging, podding depth, disease resistance, or maturity ratings.”

Gabert says that growers should also look for a comparison of two varieties where a single field is split and they can see side-by-side differences in growth pattern and yield on their farm.


Gabert says important new traits will be available for next year, including voluntary blackleg gene identification on the seed bag, multi-gene blackleg varieties, improved clubroot resistance and sclerotinia tolerance incorporated into varieties suitable to a wider geography.

“Scouting in the previous season to determine the need for those traits on your farm is even more important than what the market offers you each fall for variety selection,” he says.

While it can be time-consuming to evaluate all the data on each variety, looking at local trial results can provide a good indication of variety performance.

Anderson says Nutrien Ag Solutions (Canada) is working on new genetics around disease resistance, in particular for clubroot. “For clubroot prevention in the field it comes down to the genetics and having a resistant variety. There really are no control measures once the crop is in the ground.”

He says growers will also start to see improvement in blackleg resistance. “As blackleg races shift in the field we need to continually refresh our genetics and bring in new resistant varieties.”


This year’s wet spring in many areas and continued tight rotations will have consequences in 2018.

“Every year is different — we had a reminder of this with a wet harvest season in 2016,” says Gabert. “This combined with late seeding means early-maturing varieties are now in demand. Weather from the previous season dictates some of the pest concerns, especially on a regional basis.” He says that in selecting varieties, it’s crucial to know which pests were present in the field when the last canola crop was grown.

Delaurier says a three-year rotation is recommended and not just rotating varieties.

“If there are weed resistance issues, insect pressure etc. in the field now, growers should be looking at rotating selections of fields, varieties and treatments.”

Gabert agrees. “Choosing more than one herbicide system in your canola has many positive attributes; the potential to manage difficult weed problems differently with your choice of system. Each system will have advantages and disadvantages inherent to the combination of herbicide and variety.”

Anderson also suggests selecting more than one variety. “I would like to see growers have a couple of hybrids at least. It is not a bad strategy to have two or three varieties on the farm to be able to evaluate how they are doing.”

There can be management issues when using more than one canola variety and herbicide in the same year, so good record-keeping will be important.

“I’ve worked with growers that have successfully incorporated three herbicide-tolerant systems into their farming operation each year, but it’s more common to change herbicide-tolerance systems by year and have a single system each season to match the canola seeded — and lower the stress level of your sprayer operator,” says Gabert.

Nutrien Ag Solutions (Canada) and Proven® Seed are hosting several trials this year including Ag in Motion plot tours (July 18-20) and will showcase not only canola but also cereals, soybeans and others.


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