Best Q&A from Agronomy Update 2026 - Part Two
Once again, a big thank you to the 654 participants who joined us for the Online Agronomy Update 2026 on January 13-14! It was great to see so many familiar faces and strong participation throughout. We hope the information provided serves as a valuable resource for your on-farm decision-making this season.
Speaker slides are available on the Agronomy Update website. Feel free to refer to them as resources.
The Q&A sessions sparked some great conversations. This is Part 2 of the best Q&A from Agronomy Update 2026. Please see Part 1 for the discussions on soil fertility, soil pH and drought management.
Crop diseases
From Session: Summary of 2025 Crop Diseases – Dr. Mike Harding
Q: How widespread geographically was Stripe Rust found in 2025?
A: I would have loved to show a map of this. The distribution was pretty closely linked to the cool and wet weather along the southwest and west-central areas of Alberta. Later in the summer it spread east and north, but the earliest sightings were close to the foothills and in the black soils of south and west central Alberta.
Q: Any thoughts as to why we are seeing more continuous instances of BLS? Are there any management strategies?
A: Awesome question. It’s something I've thought about a lot. I suspect two things: 1) more BLS pathogen travelling on seed due to the emergence in USA, and 2) increased conditions conducive conditions. The final reason might be hanging on in farm-saved seed. When diseases like this emerge it's rarely just one factor that is responsible, but the general increase across the North American plains in USA and Canada is my guess at the biggest factor.
Q: For those planning on cereal on cereal acres that had ergot infections last year, any advice/cautions? Shorter season cereal vs longer season cereal?
A: Yes my advice/caution is "don't do that". Those ergot sclerotia from 2025 can’t produce a long enough mushroom stalk to grow more than about 2", so if the sclerotia are buried deep enough, they can’t be a problem. However, short rotation and excessive tillage are not a great recommendation. Best case is to grow non-host for a year or two. Definitely not highly susceptible crops (rye) or cultivars.
Ensure adequate copper fertility!!!!!!
Weed Management
From Session: The Resistance Report: Tracking Alberta’s Hardiest Herbicide Hinderances – Dr. Charles Geddes
Q: If you have resistant wild oats (group 1+2), would a multiple MOA herbicide that contained group 1 and 2 chemicals help control both types of weeds in the field to help combat this?
A: Great question. When we are talking about resistance, it depends on what scale you are actually diagnosing resistance; whether at the population scale or plant-level scale. You can see how within your population, you have group 1 resistance in a certain proportion of the population, and group 2 resistance in a certain proportion of the population. Less proportion would overlap and have both group 1 and 2 resistance. In that way, using something that does have both modes of action together may be a viable option to help you gain some control with herbicide resistant wild oat.
In addition, all of the modelling that has been done, not necessarily targeting wild oats but other weed species, suggest that mixtures of multiple modes of action should help delay selection for resistance. The question is: how does it work out once those types of resistance are already occurring in the fields. I’ll add on top of that resistance in wild oat is immensely complex where we are dealing with multiple target site mutations; as well as stacked on top of that metabolism-based resistance, which tends to be broader spectrum. So it creates a lot of unknowns. But at least what I’ve seen to date suggests that it should be a viable option to help regain some control.
Q: What about the rapid tests for wild oats being done out of Ontario - are they applicable to the wild oats here in Alberta?
A: Current genetic tests will only identify target-site resistance in wild oat. They will not identify metabolism-based resistance. In addition, they will identify presence of a target-site mutation, but not if it is present on 1, 2, or 3 of the ancestral genomes in this hexaploid species. Further, there is little evidence to suggest which are expressed dominantly. Our past research on metabolism-based resistance in wild oat suggests that it occurs frequently. Therefore, while current genetic tests will identify a target-site mutation, there is little evidence to link them to a phenotype observed in the field, and ignore enhanced metabolism. This is why whole-plant bioassays remain the standard for wild oat resistance testing (Group 1 and 2).
Q: Given current farming techniques - what is your best estimate till we see Glyphosate resistant Wild Oats (given they already occur elsewhere in the world)?
A: I won't put a timeline on it because the biology of wild oat is immensely complex. Any estimate would be wildly inaccurate. One clarification though... the case of glyphosate-resistant wild oat was redacted after further consideration. I looked at their evidence and agree that it was not resistant. That said, I do think that it is only a matter of time given the large selection pressure in our region.
Q: Hypothetically, I have a field with 50% pinoxaden resistant wild oats and 50% susceptible. My option is to spray pinoxaden or nothing. Is it wise to spray?
A1: The answer is a matter of perspective. Spraying pinoxaden again will only further select for resistance, but you will have some control (especially on the susceptible plants but also likely some stunting of the resistant ones). So you will likely protect some yield this year, but also make the problem worse for subsequent years. Alternatively, you could not apply and take the yield hit this year to help preserve long-term control in subsequent years. It is important to note that incomplete control can select further for resistance. When metabolism is involved, this could mean selection for resistance to other herbicides (or modes of action) that have not been used on the field (or even discovered yet).
A2: There are some resources from the resistant wild oat action committee that might be useful in thinking through this type of situation:
Interpreting herbicide resistance test results part 1: Putting the results in context
Interpreting herbicide resistance test results part 2: What do the numbers mean?
Q: Can confirmed Group 1 resistant Wild Oats transform over a 10-year period to become susceptible again?
A: Some resistance mechanisms also confer a fitness penalty, meaning reduced ability to successfully contribute to further generations (competitiveness, seed production, etc.). That said, I dont know if this occurs with mechanisms conferring group 1 resistance in wild oat. More research is needed to understand this. Undoubtedly, it will also depend on whether resistance is conferred by which target-site mutations and/or enhanced metabolism.
Q: With resistance costs rising, what is the "low-hanging fruit" for farmers to implement integrated weed management (IWM) today?
A1: SILAGE!!!
A2: Higher seeding rates - increase your crop competition.
Q: What about the rapid tests for wild oats being done out of Ontario - are they applicable to the wild oats here in Alberta?
A: Current genetic tests will only identify target-site resistance in wild oat. They will not identify metabolism-based resistance. In addition, they will identify presence of a target-site mutation, but not if it is present on 1, 2, or 3 of the ancestral genomes in this hexaploid species. Further, there is little evidence to suggest which are expressed dominantly. Our past research on metabolism-based resistance in wild oat suggests that it occurs frequently. Therefore, while current genetic tests will identify a target-site mutation, there is little evidence to link them to a phenotype observed in the field, and ignore enhanced metabolism. This is why whole-plant bioassays remain the standard for wild oat resistance testing (Group 1 and 2).
Q: Given current farming techniques - what is your best estimate till we see Glyphosate resistant Wild Oats (given they already occur elsewhere in the world)?
A: I won't put a timeline on it because the biology of wild oat is immensely complex. Any estimate would be wildly inaccurate. One clarification though... the case of glyphosate-resistant wild oat was redacted after further consideration. I looked at their evidence and agree that it was not resistant. That said, I do think that it is only a matter of time given the large selection pressure in our region.
Q: Hypothetically, I have a field with 50% pinoxaden resistant wild oats and 50% susceptible. My option is to spray pinoxaden or nothing. Is it wise to spray?
A1: The answer is a matter of perspective. Spraying pinoxaden again will only further select for resistance, but you will have some control (especially on the susceptible plants but also likely some stunting of the resistant ones). So you will likely protect some yield this year, but also make the problem worse for subsequent years. Alternatively, you could not apply and take the yield hit this year to help preserve long-term control in subsequent years. It is important to note that incomplete control can select further for resistance. When metabolism is involved, this could mean selection for resistance to other herbicides (or modes of action) that have not been used on the field (or even discovered yet).
A2: There are some resources from the resistant wild oat action committee that might be useful in thinking through this type of situation:
Interpreting herbicide resistance test results part 1: Putting the results in context
Interpreting herbicide resistance test results part 2: What do the numbers mean?
Q: Can confirmed Group 1 resistant Wild Oats transform over a 10-year period to become susceptible again?
A: Some resistance mechanisms also confer a fitness penalty, meaning reduced ability to successfully contribute to further generations (competitiveness, seed production, etc.). That said, I dont know if this occurs with mechanisms conferring group 1 resistance in wild oat. More research is needed to understand this. Undoubtedly, it will also depend on whether resistance is conferred by which target-site mutations and/or enhanced metabolism.
Q: With resistance costs rising, what is the "low-hanging fruit" for farmers to implement integrated weed management (IWM) today?
A1: SILAGE!!!
A2: Higher seeding rates - increase your crop competition.
From Session: Wild Oats: Managing a Decades Old Problem with a Shrinking List of Solutions – Maury Micklich
Q: Comment on heavy harrowing inducing wild oat dormancy
A: If you have a thick layer of straw that is forming a mat, wild oat seeds can enter dormancy underneath that mat of straw. If you can spread the straw out and let the wild oat seed sit on the surface, I don’t think you would induce dormancy there.
Q: What target plant population would you suggest for black soil zone to compete against wild oats in wheat and barley?
A: Based on speaker’s answer live: 32 plants/ft2 is a good balance. Upwards to 35 plants/ft2. Higher plant density poses higher lodging risks in the black soil zone. It’s a balance of compete with wild oats without lodge the crop flat.
Q: In Southern Alberta's drier regions, we worry about inter-plant competition if we increase seeding rates too much. How do you find the 'sweet spot' for seeding density that smothers wild oats without starving the crop of moisture?
A: Based on speaker’s answer live: You tend to lose more bushels to wild oat competition than the intercrop competition within the crop. Intercrop competition you might get a smaller seed size, but it’s a smaller loss than wild oat. In the long run, if you can’t control the wild oats, you are not competing it enough, it will rob you way more than the intercrop competition. I would be less worried about intercrop competition that the competition of wild oat.
Q: Where do you see the combination of swathing weedy fields as soon as crops are ready for swathing to capture more Wild Oats seed and then following with a Combine fitted with Harvest Weed Seed Mills?
A1: Will likely still have seed drop, as I showed at time of desiccation, which is close to swathing timing, lots of seeds were dropping already. Need to implement crops that mature earlier vs trying to speed up harvest of our current system. Seed destructors I really like, just not for wild oats due to said seed drop. Only way it works effectively is to be in early enough before seed drop.
A2: Combining early maturing crops with swathing with impact mills has shown benefit - particularly going to something like a fall crop where you get the improved competition (assuming it doesn't winter kill) plus early maturity so less seed drop. Producers with mills are saying they are seeing more benefits than expected on wild oat. It's anecdotal but seems like the kind of surprise we'd like to have in terms of better than expected rather than worse!
From Session: Movement of Kochia North in Alberta – Dr. Breanne Tidemann
Q: Since most kochia seed remains viable in the soil for only 1–2 years, will fall-applied herbicides or kochia seed control in the fall significantly reduce the kochia population in the spring?
A: Managing kochia seedbank is absolutely going to help manage kochia as a weed. How you do that is going to depend on your situation, and what areas we are talking about. Preventing kochia seeds from entering the soil is going to be a beneficial practice. That can be easier said than done, because if you missed a couple of weeds on an edge, or even when you mow them, you are going to see them just grow prostrate, where those bottom branches you can’t get with a mower will still set seeds. So getting those seeds are another conversation.
Fall-applied herbicide, if you got precipitation, if you are using a residual herbicide that is effective on kochia, that can be a beneficial strategy. But that’s going to affect your seedlings in the spring more so than seed production in the fall.
Q: What is the kill rate of the various Combine harvest weed seed mills on Kochia?
A: Based on speaker’s answer live: the kill rate for the kochia seeds that DO enter the seed mills is high, about 98-99%. However, it’s what doesn’t enter the seed mill that’s the problem. The bottom 6 inch of kochia can still have around 2000 seeds that are going to return to the seedbank. Another issue with the seed mill is: kochia can be still green at the time of spring cereal harvest. The green material with higher moisture may cause trouble to the combine and the mill
Have more questions about the topics above? Feel free to reach out to Agronomy Update 2026 planning committee, at rxia@albertagrains.com. We will help direct your questions to the experts. Also, feel free to reach out directly to the speakers. Their info can be found on Agronomy Update 2026 Agenda.