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The Cropwalker - Volume 4 Issue 29

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Crop Conditions

Weather we continue to have the crops ahead of normal by about a week. Winter wheat harvest is practically complete. We have set an all time yield high. Biggest factor was weather but some other practices helped. (See below) Lots of seeding of cover crops, weed control and tillage in wheat stubble. Corn is at least 1 week ahead of last year. This is the week to check for corn rootworm in second year corn fields especially if you used genetics to control them. Lots of bugs in these fields. Have Japanese beetle and others. Soybeans are tall and lush. Soybean aphid spraying in some fields. You need at least 250 aphids per plant and increasing to warrant spraying. Research shows that spraying fungicides can increase aphid numbers. This has been noted by Ryan Benjamins CCA in the Sarnia area, “One producer only has higher aphid levels where we sprayed fungicide for white mould. Coincidence?”. Some fields have spider mites at levels warranting control. Expect white mould to continue with frequent rains and lack of sunlight hours. Nothing you can do now. Tarnished plant bugs are in some fields. They can sting beans like stink bugs and make IP beans unacceptable.  Forages we went from “maybe not enough to where do I put it all” Probably a good year to terminate older stands. Younger stands produce more per acre, so consider getting rid of any stand seeded in 2019 or earlier. For stands you are keeping and harvested 50 % more than other years, be sure to fertilize for good yields next year. If your normal yield is 4 tonnes per acre you are removing 60 lbs./ac P2O5 and 220 lbs. /ac K2O. At 6 tonnes per acre, you are removing 92 lbs./ac P2O5 and 330 lbs. /ac K2O. If you want good forage yields next year, you have to fertilize this year.


Q I just checked my first-year soybeans and they are pale and no nodules. Is it too late to add nitrogen?

Ans Normally we like to see nitrogen applied to poorly nodulated soybeans in early to mid-July. I still believe you will get some benefit by applying nitrogen now.

How many nodules do I need in soybeans to maximize yield?

If you had assessed at R1 to R2 that you had less than 10 nodules per plant (only 10 are required to reach 90% yield potential, regardless of size), you would apply 50-75 lbs./ac of N. Ideally this would be a dry product applied after the dew is off to minimize burn on the leaf foliage. Liquid products can be used as well but keep leaf burn in mind when decide what product and application timing/method. To get a response, the main factor is to ensure soybeans are into pod fill. If applied too early, essentially no response was noticed, see data below. Alternatively, if you want to do a nitrogen trial on soybeans. 1) Wait until pod fill, 2) do not use low rates of “safe” foliar nitrogen, put 50 or 75 lbs. actual N as top-dress!

Here is an interesting link to assessing soybean nodulation

Assessing Soybean Nodulation – Manitoba Pulse & Soybean Growers

Assessing Soybean Nodulation – Manitoba Pulse & Soybean Growers

Timing Assess soybean root nodules each year, regardless of the field history or inoculant strategy. The ideal time to assess nodulation is at the R1 (beginning bloom) stage. Root nodule assessment…

Two Spotted Spider Mites

The symptoms from this pest are evident before you find them unless you are doing some serious scouting. Typically, they show up first around the outside of a field. Damage is visible in the form of white stippling (dots) on the upper leaf surface from the sucking mouth parts, and plants appear sand blasted or dusty on the underside of the leaves. From the road, a soybean field may look grey if there is an infestation, or brown if the leaves are dropping off and the plants are shutting down and dying. If you check the under surface you may see two spotted spider mites if you have good eyes. Two spotted spider mites are yellow-brown with two dark spots on their abdomen, to help with identification shake the leaf over a white piece of paper. Life cycle They typically move from the edge of a field or from a harvested wheat field to the edge of a soybean field, then be moved further into fields with the wind, using a “balloon” made of spun webbing. A single, un-mated spider mite can be the start of a new colony and under hot conditions infestations can grow quickly. Spider mite females can reproduce without mating. There can be 5-7 generations per year. Rain will also help plants by reducing drought stress but will not reduce numbers if you are already at threshold. The only product registered for control is dimethoate (Lagon/Cygon/Dimethoate 480).

Q Can I broadcast cereal rye and annual rye grass now?

Ans You can. I have seen it done successfully a number of times. I like to work the ground so you have a good seedbed. May have to work at least twice. I like to roll the ground with the last pass. Broadcast the seed and then work in shallowly and pack.

Q How much leaf damage can a soybean field sustain without losing yield?

It doesn’t matter if defoliation is caused by insects or hail or diseases.

Figure 1 - OMAFRA Defoliation in Soybean Thresholds

Cover Crops Seeding and Management

We have received a lot of questions so will try to answer them all in an organized matter.

In all cases you must decide on how you will control weeds. Preferred choice is a burn down before planting. Second option is tillage. This is especially appropriate if applying manure or fertilizer. Liquid manure is a great source of moisture and nutrients 5,000 imperial gallons per acre liquid manure equates to ¼ inch of water.

Cover crop review

Reasons include,

1) feed, this fall or next spring,

2) build organic matter,

3) keep soil protected from erosion.

4) weed suppression

5) improve soil aggregation/infiltration.

6) Reduce off site movement of water-soluble nutrients.

The species you use will depend on which of the above is your MAIN reason, a second consideration is when and how you plan on planting next.

Double Crop Forage after Wheat

The standard is oats. You seed at the traditional 2 bus/ac which is 68 pounds per acre. I can’t find any research to suggest a higher seeding rate. A lower seeding rate will give more tillering. Planted right after wheat you will get a good yield if you apply 40-50 lbs. N and spray a fungicide. Almost all oats grown in Ontario develop crown or leaf rust (will be some differences between varieties on susceptibility). Any of the common fungicides will control rust on oats. Spray at flag leaf or earlier if you see it developing. You could get some regrowth this fall. It dies over winter, typically no problem with green growth next spring. There have been fields where a lot of top growth interfered with spring seed bed. In that case light tillage or row cleaners helps. Addition of peas an option. Peas are normally sown at about 120-130 lbs. per acre. Sowing 10-20 pounds per acre should increase protein a bit in the feed when planted after wheat. Many common mixes are a 50/50 mix, or a 25/25/50 pea mix. These are usually seeded at 100 lbs./ac. Research has shown a 50/50 mix can increase protein by 2-3% depending on when harvested.

Cereal rye Does well after wheat. Will out yield oats and you do not need to spray for rust. There is winter rye and spring rye. For cover and a crop this fall plant spring rye. For cover this year, and a crop next spring plant winter rye. I have not heard of anyone planting a 50:50 blend to get feed this fall and next spring. But it should work. Cereal rye weighs 56 lbs./bu and is seeded at 1.0 to 2.5 bu/ac. Higher rates if broadcasting with fertilizer and working in. Higher rates when seeding late or planning to harvest for feed. There are producers putting down a mix of Oats and Winter Rye as well. You will need to cut this blend above the growing point of the winter rye to ensure it over winters.

Triticale can be seeded instead of rye. Triticale is a cross between rye and wheat so expect yields similar or better than cereal rye. There is also spring and winter triticale. Spring triticale should be planted if you want a cut this fall. Winter triticale requires more management.

Annual Rye grass (Forage type) Is a favourite with dairy farmers. If you source the right seed, expect a good cut this fall and also next spring in time to plant soybeans. A nice rotation is wheat, annual rye grass, soybeans then corn. To get best yields you need either manure or fertilizer nitrogen at planting and next spring. You need a minimum of 40-50 N and ideally 10 units of S next spring. Seeding rate about 20 to 40 pounds per acre depending on species. Caution some growers have gone away from annual ryegrass because of difficulty in controlling it in subsequent crops. There is a probability some annual rye grass seeded in Ontario is glyphosate resistant.

Building Organic Matter (OM)

All of the above forage suggestions will build OM. Leaving top growth increases the amount of OM. However, the underground organic matter is more crucial to building soil OM levels long term. If you want to build organic matter, even if not harvesting your cover crop, the best way is to apply nitrogen (25-40 lbs./ac) to get more growth. Some of the other annual cover crop species will add organic matter but probably not statistically more than oats, cereal rye or rye grass. The addition of other species can help build the diversity of soil microorganisms, but I cannot find any research to show a yield benefit to multiple species.

Protecting against erosion

The traditional crop has been cereal rye. It will control weeds, especially the current strains of Canada Fleabane. We have seen how Canada fleabane can adapt but have not seen it adapt to surviving suppression from cereal rye.

Dealing with Soil Compaction

There is research in Kentucky on fragipan soils (cement like soil structure) showing that annual ryegrass is the best cover crop in breaking up and dealing with soil compaction on clay soils. The caveat is trying to terminate it and ensuring the seed source you bring on farm does not have glyphosate resistant species. If it, does you can control it with a number of herbicides in both corn and soybeans.

Other Notable Cover Crops

Red clover is still a favorite of mine, but the acres go down every year. You must control fleabane in the fall and there are lots of opinions. If you have red clover and it is patchy you can no till oats into the field. Where the clover is good oats will not grow. Red clover will add more soil organic matter than the annual cover crops. Too late to establish at this point in the season. If you want a fall seeded clover, most common is crimson clover.

Sunflowers are very showy in a cover crop. You do not need very many. A full stand of sunflower is about 20-22,00 plants per acre. There are about 5,000 seeds per pound of sunflowers. I made the mistake of planting 2 ½ pounds of sunflower for the cover crop demonstration one year at Canada’s Outdoor Farm Show. Result was they overtook the other species so we had to cut them off. So, quarter to half a pound of sunflower seed is lots.

Ear Leaf in Corn

The video below highlights the importance of the ear leaf in corn production. Winfield ran a trial where they removed all the leaves from the plant tasseling, the all the leaves above the ear leaf, and all the leaves at the ear leaf and above. Yield results in table below. (Yes, there is an advertisement at the end of Winfield adjuvant, but the importance of ear leaves is great.)

Plant Physiology Demonstration

Q What species should I seed for pasture?

Ans It really depends on what type of pasture/pasturing you want. There is no research on the best mixes. Each species behaves differently. Once you blend them, they will respond differently than in a pure mix. For instance, timothy grows well over different soil types but if grazed heavily you will kill it out. The fescues and bluegrasses tend to last longer but are lower yielding than some other species. Best bet is to pick a mix you believe should work and then manage it the way each species dictates. Then be willing to reseed in 4-5 years. The beauty of pasture is that it builds soil. Ideally you rotate pastures. Permanent pasture mixes for rough land are a different story. Page 71 of OMAFRA Publication 811 has a description of the various species, characteristics, and uses.

Assessing Soybeans for White Mould Yield Losses

It’s a bit early to do that at this stage, best time for calculating yield loss is closer to when you would time for pre-harvest timing in soybeans. As a rule of thumb, for every plant you find, it’s 1 bushel of yield loss per 50 plants. You can have quite a few plants, and still not experience yield loss, simply because you had strong yield potential in those fields.

Hands-Free Hectare

Was started in the UK in 2017 to prove that 1 hectare (about 2.5 acres) could be farmed without human touch (100% automously) with existing technology. It was done crudely, and the yield results were not what you would expect on more commercial fields, but the two or three agricultural engineers on the project did soil sample, plant, spray, and harvest a crop without setting foot in the field. Since then, the engineers have expanded the project to 35 hectares.

You can follow the 35-acre project at https://www.handsfree.farm/ and the 1 hectare “test” project results at https://www.handsfreehectare.com/

Hands Free Farm - Headland drilling Middle Moor

Hands Free Farm - Headland drilling Middle Moor

Drone footage of our first autonomous drilling on the HFF Following poor winter weather and then UK lockdown due to the coronavirus pandemic the HFF team have...

Why is there an even number of kernels on a corn cob?

Each of these ridges will differentiate into two rows of spikelets running down the length of the ear. Because spikelets always develop in pairs, the potential number of rows will always be even, barring any abnormal environmental conditions, pollination failure, or special development cases. – Rachel Veenstra - KSU

Odds or evens? Ear row edition. (wixsite.com)

Setting yourself up for success with winter wheat – Low hanging fruit

I’m going to stand on my soap box on wheat planting for the next couple of months, because the results are very fresh for those doing it right.

1)    Plant by seed count, not weight. Adjust for soil type/planting date.

2)    Plant deep enough, and ensure the row closes

3)    Use starter phosphorus. Especially on low to medium testing soils. Ideally at least 50 lbs actual P2O5.

4)    Fall weed control. The emerging crop should see no weeds in the canopy.

5)    Use the most current genetics. For those running old wheat genetics, your liking giving up 0-10 bu/acre.

"Take my assets - but leave me my organization and in five years I'll have it all back."

— Alfred P. Sloan