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The Cropwalker - Volume 2 Issue 24

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Crop Conditions

Winter wheat – lots of fields sprayed last week for fusarium control. Growers were trying to spray when a significant amount of the field was at right timing. If your field is really uneven you could spray a second time. The concept is that if when you sprayed the first time a significant % of the heads were not at day 1 they would be when you sprayed the second time. You are only allowed to spray Prosaro or Caramba once a season. So, if you sprayed one product you would have to spray the other if you are going to spray twice. If you do spray twice please let us know. Corn - from just being planted to 8 leaf stage. Not many acres will be knee high by the first of July. The next “yardstick” to watch will be tasseling time. We want to have corn tassel around August 1st to reach natural black layer by first frost. Otherwise corn will brown layer which generally means lower bushel weight but still good feed quality. Soybeans – more acres are planted. Probably 90% done by now across Ontario. Earliest at first trifoliate. Soybeans will flower based on heat and hours of sunlight. Soybeans normally start flowering around July 1st. Expect later planted soybeans to flower earlier than normal based on stage of development. Spring grain – Earliest planted is in the boot stage. Majority of the crop is in the late stem elongation. Later planted has tillered and is just entering stem elongation.  If you planted oats for feed consider applying a fungicide for rust control. Highly recommend a two-pass fungicide system in a year like this on Spring cereals. Forages – first cut is done with a good regrowth on most fields. Some fields with poor alfalfa appear to have more alfalfa regrowth than expected. The basal buds on the crown of the plant that did not grow for first cut have started to grow. Some growers no tilled annual rye grass into poor stands. The annual rye grass is off to a good start and should have great yield and decent quality for second and third cuts. If you are in this position apply at least 60 units of actual N with sulphur. Consider using ammonium sulphate as part of the blend.

Picture 1 - Ryegrass seeded into Winterkill Alfalfa

Experience from Flat Fanning UAN on Corn

Deb Campbell of Agronomy Advantage commented that last year a grower had flat fanned 28% UAN and Acuron on his corn at the two-leaf stage. It took about 4 weeks to recover from the application.

Rolling Soybeans

This helps to push down stones and in general give a leveler soil surface to harvest soybeans. Later planting means the lower pods will be lower this year. You should wait for all the beans to emerge before you roll. Nice to have beans at unifoliate to first trifoliate. If you roll in the middle of the day the beans are more “flaccid” (unfirm, slack) and less likely to snap off. There are some reports of rolling beans to “stress” them to get better yield. I don’t think this is the year to add more stress to the beans. Rolling beans is not rocket science. You start rolling when you think you should. After you do a round get off and look.

Table 1- OMAFRA Research on Rolled Soybeans v. Various Stages

Soybean populations – if in 7” rows 90,000 plants give 87% yield. With 14-30” rows you only need about 65,000 plants to give 87% yield. This is assuming the soybean variety is adapted to wider rows.

Nitrogen on Corn

How much has been lost, how much is there, how much hasn’t been released, how much should you add. I do not believe any one knows the answers. OMAFRA is doing a PSNT summary across Ontario. However, this will not indicate how much more nitrogen will be released from the soil this summer. Warm wet conditions more organic matter is broken down and N released. Will the summer be warm and wet or hot and dry or cool? Suggest that you keep total amount of N similar to other years. Base it on yield and soil type and historical rates. Total amount of N is dictated by yield but also corn price. Higher corn prices suggest using a higher N rate.

Post Emergent Herbicides for Glyphosate Resistant Fleabane in IP Soybeans

You really have only one choice. That is FirstRate. Used with a non-ionic surfactant and 28% UAN according to Paul Foran, Corteva, should control fleabane up to 20 leaf fleabane. This is a very large rosette, but prior to bolting. In the southwest and Niagara this may not work because the glyphosate resistant fleabane is also resistant to group 2 herbicides. FirstRate is a group 2 herbicide.

Ragweed Control in IP Soybeans

If ragweed got by your pre emerge product there are some choices. Basagran, Reflex, Classic (if not 2 group resistant), will control smaller ragweed (2-6lf) Blazer will control ragweed up to 8 leaf.

Spraying Reflex, Pinnacle, and Classic on Hot Days

Reflex is safer on white and black beans than on soybeans. If spraying soybeans you cannot reduce the surfactant rate and maintain weed control. On hot days, it is best to wait until 5:00 p.m. before spraying. If you can wait until later in the evening, even better. You want the plant to be able to breakdown the herbicide in the first few hours after application. The same is true with Classic and Pinnacle. These three products can all damage beans. You have to decide if the weeds will hurt yield more than the damage the herbicide will cause.


The gray field slug (gray garden slug) loves crops and is a pest in corn and soybeans. It is not native to North America. Every slug is born with male and female parts and everyone is capable of laying eggs. Mating generally occurs in the fall, but continues in the spring. Adult slugs over winter and lay eggs when conditions are right. Eggs are laid in clusters of a dozen or more. Each slug can lay 500 eggs. They lay these in soil cavities under residue. Eggs take 2-4 weeks to hatch. They begin feeding early spring if moisture is present and it is not hot. They are called gastropods and have their mouth located on the top end of their foot. They are nocturnal feeders. They don’t chew holes but their mouth is like a file with hundreds of teeth that rasp a hole as it is eating. Chemical control is limited to baits. (Slug-Em, Deadline M-PS, Sluggo) Expensive. I have heard of growers trying to spray 28% on emerged crops to burn them off at night. Not sure how successful this is.

Should I correct Mn Deficiency?

Getting a number of calls on funky coloured spring cereals. No real hard and fast numbers on if it is worthwhile correcting. Some of the fields I have seen certainly would benefit from a top-up. Data suggests that you could see up to a 30-40% yield loss by not correcting Manganese deficiency in spring cereals. I would expect this to be a worst-case scenario, and not every part of the field will be exhibiting these symptoms.

Can I do a tank mix of herbicide/foliar fertilizer/fungicide?

There are two questions to be answered when a call like this comes in.

1)    Will it tank-mix? Best thing to do is a jar test. Process is quite simple, mix the proportion you would normally use on 1 acre in a 1 L mason jar, see if any reaction/precipitation occurs after 1 hr, and then 24 hrs. If you would normally apply it at 10 gallons/ac, divide all the materials by 40 to get the same concentration for 1 L.

2)    Will there be a crop response? Just because it mixes together does not mean the plant won’t have a crop response or impact by the surfactant load. I like to use the rule of 2 of 3. You can mix most products together if you only pick 2 of the many you want to put in the tank.

N Rate on Winter Wheat that was slated for Roundup

Have winter wheat that was supposed to get the axe and didn’t, and is now in head? After a brief survey of a few agronomists, the suggested minimum rate would be 50-60 N and 10 S. There are no guarantees this will improve yield significantly. Recommend using a high-clearance spinner to make the application. If the wheat is already at the milk/soft dough stage, take the lesson and move on, additional nitrogen is too late to make any impact on yield.

POST Anthesis UAN/N at Heading on Hard Red Winter Wheat

If you decide to do this on your Hard Red wheat to improve protein content, the optimal timing is; Wait until flowering is nearly 100% complete. You might see a few stray anthers here and there, but the majority of wheat berries will squeeze out clear liquid. If the berries are milky, it’s too late for protein enhancement. Absolutely do not apply during flowering. (Source: Dr. Dave Franzen NDSU.

What can I spray in Oats for annual grasses?

Unfortunately, Oats are one crop that there are no products available in-crop to control annual grasses.

Can I tank-mix Distinct with Roundup in Corn?

While I have seen farmers tank-mix this combination, it is not a supported practice due to crop response.

Adjuvant Volume/Volume Chart

Whenever I don’t have this chart at my side during post-emerge spray season, I’m not long looking for it. Here’s a copy for you as well.

Table 2 - Surfactant/Adjuvant Chart

How much can Perennial Sow-Thistle reduce yields?

In corn, 4% at 1 plant per meter squared, 15% at 5 plants per meter squared. Soybeans 5% at 1 plant per meter squared, 20% at 5 plants per meter squared. This is under the assumption plants are not controlled in season.

Best Herbicides for Perennial Sow-Thistle in Conventional Corn and Soybeans

For conventional corn, the following are the top-rated options;

Marksman – 90% @ 1.5 L/ac, Distinct – 80 % @ 115 gr/ac; low rate dicamba – 80%; Peak 80%.

For conventional soybeans, the top-rated options are;

Clean Sweep, Basagran Forte, Blazer or Classic all provide similar level of top growth control at 70%. Best option is glyphosate pre-harvest, to reduce populations long-term.

Alternatively, if you have a roundup-ready crop planted; glyphosate @ 1 REL/acre is the best value for the control – 75%. The 2x rate provides 85% control.

Forage Production in the Maritimes

Last week I worked in the Maritimes, meeting with serious forage producers. Some were feeding livestock, mainly dairy. Some were using forages to build soil in their potato rotation. Most were direct seeding. Most have gone away from brillion seeders. The ground now is uneven due to compaction and less tillage. Brillion seeders work well on level ground but not so well where ground is uneven. The successful growers were all using drills. The drills were better able to follow the ground contour. They were all using grass in their mix. Few using timothy. Most were using a rye grass, tall fescue and a lot were using festolium. It was obvious that no matter what % grass you seeded, you never ended up with that % in the feed. Many had seeded annual rye grass this spring into killed out areas. They will have a great second and third cut. They had a lot of winter kill. In general fields seeded in 2018 over wintered much better than older stands.

Section Control on Planters -> 7% min $200/acre

As planting season is wrapping/wrapped up, take a quick look at your planted acres vs. those of the field boundary if you are not currently using section control. Aaron Breimer, General Manager of Veritas, mentioned that the average overlap in a corn field in Ontario is 7%, and that the minimum economic loss between excess seed and lost yield on those areas is $200/acre. Will it be zero with the use of row shut offs or electric drives? Not likely, but 1 or 2% seems quite achievable. Aaron also had data on soybeans, which came out to $100 per acre, between seed and lost yield. Doing some rough math, $200/acre seems reasonable on winter wheat if using an air drill with certified seed and dry fertilizer.

Table 3 - Expected improved margin using row by row section control in Corn
Table 4 - Expected improved margin using row by row section control in Soys
Table 5 - Expected improved margin using section control in Wheat
How To Use Precision Agriculture Data On Your Farm

How To Use Precision Agriculture Data On Your Farm

Aaron Breimer of Veritas takes a look at local agronomic case studies and precision ag. He talks about soil sampling, selective fungicide, automatic row shut...


"You don’t need to adopt Precision Ag, you only need to compete with those that do." * - Aaron Breimer

*When Aaron made this comment, he was of the opinion that if you are competing against those using precision ag, they know what they are doing, and are making headway using it. If those that are using precision ag are not making any progress or having any success, i.e. just spinning their wheels, then you are further ahead not adopting the practice.