12 min read

The Cropwalker - Volume 3 Issue 47

Always read and follow label directions.

December 2020 Complimentary Issue

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Imagery Programs for Field Crops

1)    Corteva -Slight Development

Chris Oldbach, an area agronomist with Corteva/Pioneer, gave me some insight into their program. I was interested when I saw some pictures, he took of a corn field at emergence. This software program uses a drone (UAV) to fly a field and take pictures. He said it takes about 40 minutes to set up the UAV to fly the field, then 15-20 minutes of flying to take pictures. Once the drone has landed the pictures are ready to download. Chris said he did a few hundred acres this year for Pioneer dealers in his area. Basically, the drone was doing a stand count. This takes the guess work and all that walking out of the picture. He said it works best when corn is at V2-3. The software is still in the development phase but believes it could help farmers a lot in the spring when there are emergence issues, and you are not quite sure how serious the issue is.

They have used it in soybean fields. But it cannot do a stand count (yet). What it can do is a gap analysis. Know how many and how big the gaps are. The images below show two corn fields. The one on the left has more gaps. Left side was corn on corn. Right side is corn after cereals.

Picture 1 - Corn Population Comparison by Cropping System

2)    FieldView Update

I spoke with Leanne Freitag, who is the Digital Interpretation Specialist with Bayer about their software program Climate FieldView. The program will be free in 2021 (need a Bayer Value account to qualify). The main uses of this software are to track as-applied field activities and use satellite imagery to monitor the crop in season. It allows you to record activities such as planting date, hybrid/variety and seeding rate. There are other activities you can record, like dropping pins in the field to make notes (permanent or just for that season). When setup in a combine, it can then record harvest information (yield). You can do a split screen analysis with the yield map to compare different hybrids or sprayed with fungicides vs not sprayed. The software allows you to take data from different coloured pieces of equipment and combine them. In season, there are 2-3 satellite passes per week to monitor crop growth. Anyone can sign up, and if you are enrolled as a Bayer Value customer, the annual fee is waived. According to Leanne (and from my experience) the software is very easy to use. And you can share the data with your retailer or Crop Consultant or anyone else who is an enrolled as a Bayer Value customer. The image below is a split screen showing yield and fungicide application map. You can get more detailed information at climatefieldview.ca

Picture 2 - Fungicide Trial Analysis in Climate FieldView

The Changing Distribution of World Corn Production in the 21st Century

Figure 1 - Corn Yield Improvement by Country as a Percentage
  • Carl Zulauf - Department of Agricultural, Environmental and Development Economics - Ohio State University

November 18, 2020 - Interesting to see average yield in various countries. Make you feel good about our Ontario yields.

Battling slugs

Some real interesting field work done by Bobby Clark and Doug Horn, extension entomologists with Virginia Cooperative Extension. Virginia State has a high percentage of corn that is no till. Slugs are a perennial problem. A common practice for them is to plant cereal rye in the fall then when it is 12” high burn it off and no till corn. In 2019 and 2018 they took notes on farms looking at slug numbers and damage in corn and soybeans. The winter of 2019/2020 was warm, so they continued one more season. Warm winters are conducive to more overwintering slugs. A common practice in Virginia is to apply an insecticide when they are doing their burn down. The work of these two extension entomologists indicated that if you used an insecticide there was more slug damage. The use of an insecticide killed the predators that ate the slugs. They found generally planting early helped corn plants outgrow slugs. Their information suggested that some type of tillage reduced the amount of slug damage. It is very interesting that they have been planting corn into cereal rye that is 10-12” high and been doing this for years without any apparent adverse effect on corn yields.

Early on farm trials with fungicides in 2020

Spoke with Marijke Vanderlaan who is an Agronomic Services Rep with Syngenta. She gave me some preliminary results from on farm trials. She promised she will have more results when all the trials are in. In winter wheat, there was a 3-4 bu/ac yield increase in fields sprayed with Miravis Ace. Vs. check, even though there was no fusarium.  In corn, Miravis Neo was consistently showing a yield increase. In over 20 comparisons about a 6% yield advantage for sprayed vs. check. The higher yielding fields showed a better response than some of the lower yielding fields. The sands and heavier soils, where drought was an issue, showed minimal response.

What is the best mix for an all grass mixture for hay?

I have asked a number of folks what they like. From my own experience I know that no matter what percentage of grass species you plant, you NEVER end up with that mix at harvest. Always one species does better, and one or more starts to thin out. Here is what I do, I like at least 1 pound of ladino white clover. I know it isn’t all grass but I like this. Then I use 1-2 pounds of timothy. It helps fill in spots in first cut. Then I like to have a mix of other grasses. The exact species depends on the farmer and the situation. I start with a ryegrass to get a quick stand start. Only need a couple of pounds. I use a fescue (generally tall fescue). Then orchard grass of a late maturing variety such as Echelon. Orchard grass must have good rust tolerance. If the grower does not like orchard grass, I will use brome. Then I use a festolium. There are different festoliums, depending on the cross to make them. The two main festoliums are crosses between fescues and rye grasses. Crosses of Italian rye grass and meadow fescue give a high yield but is not persistent. They tend to do better in a short rotation. Festoliums that are a cross between a perennial rye grass and tall fescue last longer. You get winter hardiness from tall fescue and higher feed quality from per rye grass. In total I want 20-25 pounds per acre of grass. The exact rate depends on seeding equipment soil type and seed bed preparation.

Red clover results from 2020

In general, when speaking with growers, red clover did well in 2020. One grower had a really good stand. Burn it off late October. Tried two different pieces of conservation tillage tools. Neither one worked. Ended up mould board ploughing it. Another person tried to make strips in late October to plant corn next year. Ended up using a strip tiller with shanks. I think this will lead to erosion. One of our readers a number of years ago made his strips in August. (see picture below) That worked well. The red clover grew good enough on either side of the strips that I felt it was a great way to do it. I spoke with one Conservation Area and they are granting farmers $10.00 per acre for up to 100 acres for any cover crop including red clover. I wish more CAs would allow red clover in their grant programs. Check with your local CA to see if there are any grant programs available or consider applying for the CAP Cover crop grant if you have a current Environmental Farm Plan. https://ontarioprogramguides.net/pc-en-esim-pd-b/

Picture 3 - Stripped tilled into red clover early works well

If you want to build Nitrogen response zones within fields, you HAVE to model water movement within the field.

Yes, that’s right, if your site specific or precision ag program cannot model water, you will likely NEVER be able to do an accurate job of variable rate nitrogen. Yes, long term yield maps can help figure out the sink side, but there is more to the nitrogen management equation than yield. What about source? Without water modelling, there is absolutely no ability to segregate areas of the field that are prone to leaching and those prone to denitrification. You will likely be unable to sort nitrogen mineralization capacity either.

But I can’t just sort those out using an elevation layer? No. Water does not move within the landscape in a straight line based on elevation, see examples of maps below.

Figure 2 - Elevation models are not suitable for nitrate sampling
Figure 3 - Zones with water flow paths, dark green is prone to denitrification.

If you want to variable mobile nutrient products such as Nitrogen, Sulphur or Boron, you MUST include the ability to model water and water movement into the source side of the equation.

YEN Notes

Last week with the YEN (Yield Enhancement Network) trials we had made a few comments on requirements for top winter wheat yields. I wanted to expand a bit on the crop physiology component on modelling yield potential, and the practical implications of this.

When calculating “Grain Harvest Index” to determine theoretical yield, the YEN research staff use the lesser of two biomass amounts; 1) 60% of light energy capture (1.4 MT biomass per TJ/ha), or 2) plant available water held in the soil to 1.5 m plus rainfall from April to July. Conversion of 18 mm per tonne biomass per hectare.

This means if you had a full soil profile going into spring, and receive rainfall from April to July, you should be able to forecast what the maximum wheat yields your field is capable of. And I suspect many growers are likely falling short of that target, simply because we don’t know what is possible.

The exciting part in my opinion is that there are weather/soil devices mated with software packages that are now on the market to forecast this in real time, one of them developed for dryland wheat/canola growing areas is Saskatchewan based Crop Intelligence. Imagine knowing what the potential yield of your wheat crop is, knowing where it is pulling moisture from, and fertilizing accordingly. This is particular importance to hard red winter wheat growers in Ontario, where protein dilution under high yields is a major issue. Or wanting to know an approximately yield potential in corn when dry weather conditions have shown up, and an expected yield potential is listed to determine if you should spray a fungicide on corn at tassel. Or perhaps we can start to forecast when leaching or denitrification of nitrogen is likely to occur in those respective areas of the field (hint – the technology is here, and the ability to forecast this not that far away!)

Figure 4 - Rough Theoretical Yield Estimate using Rainfall

With just using rainfall as the limiting factor, 188 bu/ac is the theoretical yield potential for the Harriston area in 2020. This does not consider other factors, such as available soil moisture, or solar radiation. Regardless, with many growers in that area in the 90-100 bu/ac range, they are only achieving about 50% of yield potential based on a very crude estimate. I did not calculate solar radiation, as I have not found an easy source for this type of information.

Crop Weather Modeling and Forecasting Crop Protection Applications

In order to do an accurate job of forecasting disease development, the forecasting model should account for both crop staging and appropriate environmental conditions for disease management. With just a disease management forecast, the model will likely have reduced accuracy in being able to predict “optimal” application windows and require more trips to the field to ensure products are applied at the appropriate time. By forecasting both crop staging and diseases development, you will be able to have both a suggested timing window and know the risk factor. This is not to replace boots in the field. Boots in the field are still required to valid the model and diagnosis other issues that may be able to be addressed at the same time, i.e. insects or micronutrient deficiency, or other diseases not being modelled. What the model will do for you is make it more efficient manage additional acres, as you will know that the timing is right to check the field for that management decision, rather than being a week too early or too late.

The last piece to making this as accurate as possible is using field placed weather stations, as there can be numerous microclimates/weather patterns within the local landscape. For example, my residence is on the boarder of two of these different weather patterns and soil types. Even though I have growers that I work with 10 KM north and south of my base, they can have two very different outcomes because of this. The platforms I have used that have not tied in local weather stations have been directionally correct, but from my experience are more prone to error, and less likely to be able to forecast down to the day on when applications should be made. Which might be fine depending on the crop, the disease being managed and your risk tolerance.

Figure 5 - Lots of soil types/micro climates in Minto Township. (Source: Ontario Soil Survey)

CCA - Soil Water Quality Workshop

In the last two issues we have had a few comments from the Certified Crop Advisor Soil Water Quality workshop, a few more notes in this week’s issue.

First up is the presentation by Kevin McKauge – OMAFRA - Water Quality Engineer. Under the Agrisuite products is a new soil survey tool to estimate the impact soil erosion due to sheet and rill erosion can have on your cropping practices. A future update should allow you to identify areas prone to gully erosion. Along with predicting tillage erosion on the drawing board/roadmap.

Erosion Mapping Tool Demo

Erosion Mapping Tool Demo

This video demonstrates how to estimate a field's risk to experiencing soil erosion due to water.  The Water Erosion Potential Risk Mapping tool demonstrated...

Clare Nelligan, a PhD post-doc at Ryerson University presented at the event on non-point source nutrient exports from Southern Ontario Agricultural Watersheds.

The goal of the work Clare is working on is to build on research completed from 1972 to 1979, that at time found 80% of variation in nitrogen and phosphate loading could be predicted from soil type (% clay) and crop type (% row crop – corn, soy, wheat).

The new study is trying to investigate the relationships between land use/management and nutrient export, assess the influence of extreme weather events and identify any differences in seasonal patterns.

A few outcomes from the research thus far (and aligns with other comments throughout the day), is that they are seeing more of phosphorus loading occurring in the fall and winter compared to past studies. Part of this maybe due to a change in winter weather and how water moves within the watersheds.

An anonymous producer’s take on Soil Management in Ontario.

Biggest issues to date are Apathy and Indifference. Very little mention of physical soil management and the importance of (the) Soil Biology that helps soil functionality. It is not a singular “Chemical” issue that has created or will provide a solution. The recognition that a harmonized approach that largely rests in the hands of the land/soil manager is of paramount importance.

Planting Soybeans Green into “Volunteer” Winter Wheat Follow-up

In the June 17th issue of The Cropwalker, we had presented where a client had “drilled” soybeans green into standing volunteer winter wheat, which was subsequently burnt off 2-3 days post planting with glyphosate and a pre-emerge herbicide program (soybeans were about ready to pop out!). After some number crunching the producer came back with the news that this trial was a better success than expected. Partially due to cropping history, but there was NO in-crop herbicide required, and it was also one of their better yielding fields out of all the soybean fields they farm. I consider that a success.

Picture 4 - Pre-Emerge Sprayer miss on plant green field (End of May 2020)
Picture 5 - Variety split in plant green field on July 25th, 2020

“Learn how to learn from those you disagree with, or even offend you. See if you can find the truth in what they believe.

– Kevin Kelly