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The Cropwalker - Volume 4 Issue 9

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Crop Conditions

This week last year corn harvest was resuming. There was some frost seeding going on. This year, we are colder than the same week last year. Winter wheat has not started to green up anywhere. This week last year we had green up. We often lose winter wheat to heaving when we have the freeze thaw cycles in March. But last two years we had significant thaw freeze cycles and little heaving. This was because of planting winter wheat earlier and deeper. Ryan Benjamins in Lambton County says about 50% of the red clover is spread in his area.  Susan Gowan CCA ON in the Niagara area says they are almost done spreading red clover. Markets spoke to a grain trader Monday morning who said you can book this year’s wheat for $7.50, corn for $5.78 and soybeans for $15.50. The trader mentioned that most large acre producers have booked crop but many growers with a small acreage have not.


Farmer Fertilizer Newsletter

If you are wanting to stay on top of current fertilizer trends and pricing, I recommend signing up for a free trial of Josh Linville’s fertilizer market summary. He is also a great person to follow on Twitter, posting many relevant posts and charts on the fertilizer market and logistics.

Justification for late applications of nitrogen on corn

Some where we have lost the idea behind late applications of nitrogen for corn. The concept is to get the same yield with less nitrogen, than if all the nitrogen is supplied up front. The marketers are suggesting you can get more yield by applying more nitrogen late, using a nitrogen stabilizer/enhancer. Hmmmm?

Question; Should I apply sulphur (S) with my first nitrogen application on wheat?

Answer Absolutely yes. I listened to a presentation from North Carolina University where they routinely get a response to S. One of the comments is that early in the season plants need S. S can come from organic matter but it takes time for that S to be released. Agronomically it makes more sense to put S on early.

Question (from a farmer in mid Perth county) I have a 40-acre field of alfalfa that is good but will terminate this year. A neighbour wants to take the first cut and then I will no till soybeans. What do you think?

Answer: If you take the first cut you will give up 15-18 bushels of soybeans, risk a later harvest and possibly a later wheat planting. With current price of soybeans, I would forego the first cut of hay. This is all presuming he harvests forage when you want and it does not turn dry after forage harvest.

Reply Good, the guy I am getting to plant my soybeans basically said the same thing.

Question: I have some cereal rye planted mid-September (Middlesex county) after corn silage. I want to take the rye for forage and then plant alfalfa. Do I need to spray off the rye?

Answer: Absolutely you must spray it off. And get ready to spray before the heads are in the boot because doing that you might actually get to the field while the heads are still in the boot. Rye advances very quickly. I have seen too many fields where the rye was not sprayed off and it choked out the alfalfa.

Supplementary question: Should I direct seed or plant some oats with the forage seed. I plan to no till the forage seed?

Answer; Make that call at planting. If seeding by May 10th I would direct seed. If May 20th I would put in 30 lbs/ac oats. In between those dates it will depend on weather. Good weather to get the crop up early -no need for oats. Dry soil conditions consider oats.

Sulphur on Alfalfa, Corn, Red Clover, and Wheat

We publish this table every year because it is easy to forget. Table gives the rate of various products. There is a ratio of N:S that some use. It boils down to higher yielding crops that use more nitrogen should have higher rates of S. For wheat you need a minimum of 10 lbs actual S per acre. Some growers are applying 15-20 lbs/ac. There are on farm trials showing the addition of sulphur to wheat helped the establishment of red clover. The soils most apt to need S are lighter soils. For corn, consider using 10 lbs /acre. For alfalfa use 15-20 lbs actual. We believe you should apply S with your first N application on wheat and corn. For alfalfa I like to get it on as early as possible. Between OM and manure applications, they can meet the rest of the alfalfa S needs.

Figure 1- Sulphur Fertilizer Products

Possible Crop Plot #3

Envita is advertised as soil inoculant for corn that makes corn roots fix nitrogen. There is limited product available for 2021 but lots to do plots. Spoke with one dealer who said they have 4 cases and each case treats 160 acres. Possible plot layout

1.     Split planter with inoculated seed in half.

2.    One acre or so receives no nitrogen except for starter N.

3.    A few acres with 50-75% of your normal rate

4.    Compare yields from these strips with your normal N rate.

Keep in mind that too often there will be little yield difference between your full N rate and 75% of your full N rate in plots. Some of this depends on location within the field landscape.

Corteva Research. Each year Corteva/Pioneer release a research summary of in field plots. Most of this research is from the US. Interesting projects

1.     Nitrogen on soybeans and yield of older vs. newer soybean varieties

This research was a 2-year study looking at varieties released between 1980 and 2013. It showed an annual genetic yield increase of 0.57 bu/acre per year. (editors note: this means that of the yield increases you are getting 0.57 bu/ac can be attributed to genetics)

They looked at “O” N and 500 lbs/ac actual N applied in 3 applications. The 500 lbs/ac actual N gave an increase of 7.9 bu/ac. (This does not mean you should be applying 500 lbs/ac of actual N to soybeans.)

Forage Oats Improves Butter Fat (BF)

Just received a call from a reader commenting on feeding oat forages to his cows. He said he and his son have noticed an increase in BF when they add forage oats to the ration. Their nutritionist has agreed that the lignin in oats grown as forage as digestible lignin. By adding this ingredient to their ration, they believe they have a 0.3 increase in BF.

Critical Weed Free Period - Fundamental

In almost all field crops (both annual and perennial), the most critical stage when it comes to the critical weed free period is the 1 to 3 mature leaf stage. In corn this is 1 to 3 leaf over. In soybeans this is 1 to 3 trifoliate. In cereals, it is tied to growing degree days, but is more or less in that 1 to 3 leaf stage. Don’t let weeds rob you during this critical plant stage. Put a plan in place NOW, to avoid losses during that time period. The next most critical time is during the early reproductive stages. If plants are water stressed during this time due to weed interference, you will suffer yield losses.

Question – I want to do variable rate, when, where and how should I be doing it and what should I be investing in to do it?

Answer – First off, I don’t think you need to do variable rate on every pass, there is only a need to do it on some passes, not all passes. First, let’s take a look at the crop rotation and input applications, and see where there are opportunities to sort out the mismatches between the current application rate and the response. This is the “art” piece when it comes to precision ag and agronomy, knowing what tradeoffs are acceptable, and which need adjusted to get the full value of what is available. Variable rate lime is certainly a large pay-off, will take that off the table, and consider the other inputs at this time.

Figure 2 - What soil applied rates should be adjusted to account for field variability?

In this case, it provides the business case that you should likely invest in the capability to do variable rate seed first, as you are unlikely to hire this piece out. The next thing to invest in would be the ability to do variable rate nitrogen, and then finally the ability to do variable rate P/K/Mg (if the capability did not come with the variable rate nitrogen), as you can adjust that as needed on less frequent basis.

Then I worked through a couple of scenarios, knowing some actual examples of what a handful of growers have had to work with.

Figure 3 - Examples of what needs to be varied when

By using what is outlined in scenario two, which is likely the case for many producers, or possible could only do variable rate corn and soybeans, I estimate you get 75-80% of the benefits of investing in maps to do variable rate, without having to own all the components to apply rate adjustments on each pass.

Budget – It’s a dirty word…

Pssst. Did you hear. Yes, the budget. We have to cut costs. Too much money being spent. When I bring up the topic of budget, I usually get a bunch of eyes rolling back, why bother. Well, that is all fine and dandy if you believe on farming under the premise that you get to be a millionaire as a farmer by starting with $ 2million dollars and spending $1 million to keep $1 million. We CAN and SHOULD do better than that.

Here is a post on budgets where your eyes might pop… $100/ac crop inputs budget to raise 100-bushel soybeans… thinking like this gets the creative juices following on what you need to do to scrap out excess dead weight and put in practices that move the needle towards your goal (whatever that is). And if you think the goal is not realistic, Brittany Bolte knows of a farm that just did that. $100/ac for 100 bu soybeans.

Put limits on yourself. Both on the financial and on the yield side and see what you can do.

Question – Why do you not recommend Classic pre-emerge?

Answer – I think Classic (chlorimuron-ethyl) is a great product in soybeans. In my experience in working with IP soybeans I want to save Classic for in-crop use, as the number of tools I can do rescue treatments is quite limited, if the pre-emerge has failed. The other reason is there are cropping restrictions with a product like Classic.  I work in an area with some Canola grown. If Classic has been used, the recropping restriction for Canola means waiting for a field bioassay. Third; if you are using Classic in the spring to improve the control of dandelions in wheat stubble going to beans, you should be doing a fall burndown instead!

Scott Nelson – Proper Nitrogen Management in No till Corn

Last week the Fluid Fertilizer Institute had a great presentation titled, “Overcoming the Yield Gap in Corn Following Cover Crops with Fluid Fertilizer”. The focus of the presentation was on how to improve nitrogen use effiency and corn yields in a no-till setting. There are many reasons to do a “plant green” or include cover crops that stay alive into spring from a soil and water quality standpoint. The challenge is that in many cases we are using nitrogen practices that were designed for full width tillage.

A few highlights;

1)    There are strong reasons to no-till corn into fields with cover crops; environmentally these fields have shown to reduce total nitrogen loading off the field by 50%, improve water infiltration by up to 50% along with other cropping system benefits.

2)    No-till fields have anywhere from 3x to 5x as much Urease enzyme present, making them much more susceptible to volatilization when urea-based fertilizers are used.

3)    In Scott’s literature summary and one year experience, they found that many of the bad experiences with no-till corn are due to the wrong nitrogen source being used. As a result, Nitrogen source, placement and timing need to be different.

4)    Scientific literature and the 2020 research trial success found that in no-till corn, the use of a NBPT nitrogen inhibitor (i.e., Agrotain Advanced) is critical to managing nitrogen losses due to the use of urea-based fertilizers.

a.     When Urea is just applied to the surface in a no-till environment, yield hits of 20-35 bu/ac, or more, are common without the use of a NBPT inhibitor.

5)    Based on Scott’s 2020 research planting corn following a cereal rye cover crop, he found that;

a.     30-50% of total nitrogen should be in nitrate form at or soon after planting.

b.     Starter N should be 30-50 N/ac from UAN using 2x0 or 2x2 placement (10-15 gallons 32% UAN or 12 to 18 gallons of 28% UAN).

c.     Follow up in crop with the remainder of the N using 28% or 32% UAN at early side-dress V4-V6.

d.     Scott did see a 10 bu/ac advantage to including cover crops in no-till corn vs no cover crops with this study once you addressed the issues with nitrogen management earlier in the season.

Soybean Herbicide Pre-Emerge Programs

Last week we reviewed the Roundup-Ready traited soybean pre-programs, here’s the rest. Next week I will cover burndown options and differences between products.

Xtend Soybean – Pre-Emerge Programs

To minimize the risk of dicamba moving off the field, our recommendation is to use dicamba as part of the pre-emerge or burndown program. Preferably at the high rate. Keep in mind what you are really paying for is the genetics, and you could treat the soybean crop as a regular Roundup-Ready field.

For those that are seed growers and must apply dicamba in-crop to ensure seed purity, I would still recommend making the application as early as possible in the growing season (as per seed contract requirements). Contact us directly for program ideas if you are in that situation.

For areas with heavy fleabane, I would stick with the Sencor based programs; Boundary+dicamba, Tavium +Sencor or Prowl + Sencor + dicamba. Please note that BASF did make note in their winter meeting that they were finding dicamba did have some antagonism with the metribuzin when it came to the control of Canada fleabane.

Figure 4 - Dicamba Tolerant Soybean Pre-Emerge Programs

Liberty Link/Enlist Soybean – Pre-Emerge Programs

If there is one weed group that Liberty is weak on, it is grasses, it can also be weak on perennials. For this reason, I would recommend using a graminicide as part of the pre-emerge program. If you have perennial grasses such as quack grass, the best you can do is add a grass product in-crop to the Liberty. I wouldn’t characterize Liberty as the solution to glyphosate resistant Canada fleabane, ensure you start clean and stay clean if you choose to go this route. Liberty is quite strong on annual broadleaves. Most Liberty Link beans have been replaced with the Enlist trait (LL/RR/2-4D-Choline) for this reason, see below.

Enlist Soybean – Pre-Emerge Programs

2,4-D Choline is strong on annual broadleaves, the challenge with this product is that it has very limited residual activity. Same can be said about glyphosate, or Liberty, which can also be applied in-crop to the soybeans. Corteva does not recommend tank mixing glyphosate with Liberty, as they require very different application rates, water volume and droplet sizes for maximum efficacy. Where would I recommend you spend your pre-emerge dollars? Controlling bluegrass, keeping fleabane in-check and controlling waterhemp would be my picks. Use the in-crop application of 2-4D-choline (Enlist-1) as a rescue treatment, rather than a must have.

Figure 5 - Enlist Tolerant Soybean Pre-Emerge Programs

Conventional Soybean – Pre-Emerge Programs

In my opinion, if you are growing conventional or IP/NON-GMO soybeans, you will likely have a grass/broadleaf herbicide from group 15 (Boundary or Frontier, pyroxasulfone) as the base, and a broadleaf herbicide from group 14 (Authority or Valtera). There maybe producers or consultants swapping out a group 15 for a group 3, like Prowl, but keeping the group 14. Regardless, to control the THREE main weeds of concern in these groups, nightshade, lamb’s quarters, and pigweed, having an herbicide from group 14 is a must, preferably from both a group 14 and 15. The FOURTH weed of concern is common ragweed, only group 14 products containing flumioxazin (Bifecta/Fierce/Triactor/Valtera) is labelled to control both group 2 and 5 resistant and non-resistant biotypes, with a rating of 7.

Figure - 6 - Conventional Soybean Pre-Emerge Programs

“If we had no winter, the spring would not be so pleasant: if we did not sometimes taste of adversity, prosperity would not be so welcome."

—Anne Bradstreet