The Cropwalker - Volume 2 Issue 30

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Crop Conditions

Winter wheat - harvest rolls on with harvest starting in central and eastern Ontario. S Ontario Essex Kent Lambton are 90+% done. Yields 40-120, probably average 78-80. Quality is good. DON levels remain low. Do not, however, delay wheat harvest. Sprouting is occurring in soft white varieties. Corn - fungicide applications are starting. You want 75% of the crop to have at least 1” of green silks. With variable fields don’t wait for the later plants. The earlier plants will have highest yield. Protect them once 75% are between 1” green silk and start of brown silk. Western bean cutworm (WBC) remains a conundrum. Spray or not. Check nearest moth traps in your area. Here is the link to the maps.  https://fieldcropnews.com/2019/04/welcome-to-the-great-lakes-and-maritimes-pest-monitoring-network/ Once you are on the map site just hover your cursor over a spot and it will tell you the moth count. As of today, very few areas in Ontario with significant number of moths. Talk with your suppliers in your area and make a decision. The insect by itself is not the big issue. It’s the larvae feeding, which can cause another entry point for fusarium (and related yield losses). It will be good when we get better genetic resistance to both fusarium and WBC. Genetic resistance is available for WBC with the Viptera trait. Check with seed suppliers in your area to find out what is planted in test plots. Soybeans - are in full flower R2 to R4 beginning of seed. Most fields too late for optimum white mould timing of first application. Spraying your first fungicide now will control other diseases and/or get plant health. Forages - second is finished or well underway. Third cut could use rain in most fields. Continue to watch for leaf hoppers. They will continue to affect yield for another month. Really check roots of stands that were seeded prior to 2018. They may look good, but most have damaged roots.

Articles

Days from tasseling to black layer

It takes about 55-65 days from silk to maturity. (there are differences among hybrids) If corn silks appeared on July 25, your crop needs to be frost-free until roughly September 25-October 5 to reach physiological maturity. If a frost hits before then, it will force a black layer (or brown layer). If in that case the corn is close to maturity, the effects on quality and yield will be minimal.

Spraying Corn for Fusarium Control

If you feed corn on farm to hogs or dairy cattle you must seriously consider spraying for fusarium control.

Another Reason Why Dairy Farmers Should Spray Corn Silage for Fusarium Control

Quote from Daryll Smith (member of Bovine Practitioners) in a farm publication “making sure feed is of good quality and free of mycotoxins” when addressing how to keep Somatic Cell Count numbers down, especially during summer months.

Summer Seeding Alfalfa

Lots of options. Main thing is good seed to soil contact and good soil moisture. You want seed in a firm seedbed no deeper than ¼-1/3 of an inch. Hard to get. You need a good seedbed. Cannot have lumps. If you are spreading manure, make sure seed bed is not compromised (lumpy) because you are incorporating manure. I have seen successful stands with no till drills, conventional drills and broadcast seeding. You have to control weeds. If you have a lot of chickweed, you must consider sowing a Harvxtra (Roundup Ready) variety. Wait for weeds and alfalfa to emerge. Spray off the chickweed and volunteer wheat, then plant your grasses. If using non-glyphosate resistant alfalfa, you could wait for volunteer wheat to come up, spray it off, then plant alfalfa.

A Different Cover Crop Approach

I have one customer who did this once and it worked well. Maybe because everything just clicked. He applied liquid manure then planted 55 lbs/ac peas, plus 55 lbs/ac oats and 120 lbs/ac cereal rye. The oats and peas grew to about 30” high when harvested in the fall. It ran 26% protein. More manure on the rye in the spring and then when rye was 3 feet high, he harvested it again. Then planted soybeans. He will try this again this year.

Soybean Staging review

R1 (beginning bloom) – First flower is detected. R1 lasts about 3-5 days. After R1, you need to look at the top nodes of the main stem with fully expanded leaves. R2 (full flower) – An open flower at one of the two uppermost nodes of the main stem. Lasts about 10 days. Near the end of R2, pods have formed at the bottom of the plant. This is ideal fungicide timing.  R3 (beginning pod) – Pod is 3/16-inch-long at one of the four uppermost nodes. Can last up to 2 weeks but on average 9-10 days. R4 (full pod) – Pod is ¾ inch long at one of the four uppermost nodes. This is the most critical time for soybean yield. Stress at this stage results in more yield loss than at any other stage. R4 can last more than 3 weeks but on average 9-10 days. R5 (beginning seed) – Seed is 1/8-inch-long in the pod of one of the four uppermost nodes. Lasts up to 3 weeks but on average 2 weeks. R6 (full seed) – Pod containing a green seed that fills the pod cavity at one of the four uppermost nodes. At the end of R6 full yield potential has been reached. This stage can last up to 30 days but on average 18 days.   R7 (beginning maturity) – One pod anywhere on the main stem has turned brown. Lasts on average 9 days. R8 (full maturity) – 95% of pods have turned brown. 5-10 drying days from this point will bring moisture to 15%.

Two Spotted Spider Mites

The symptoms from this pest is evident before you find them, unless you are doing some serious scouting. Typically, they show up first around the outside of a field first. 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 on 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)

I didn’t scout for leaf hoppers in my new seeding and now my new seeding is really suffering because of them. What do I do?

The above is a true question from a reader. (He didn’t think we were serious about spraying for leaf hoppers) The issues are, you must control the leaf hoppers, and, remove the apical dominance of the alfalfa plants by clipping. You can either spray and cut 1-2 days later, or, clip and spray right after clipping. You want to leave at least 3” of top growth. My preference is to spray first and then clip. Product of choice is dimethoate (Cygon/Lagon) because it lasts longer and is not prone to breakdown. Matador will also control leaf hoppers, but it breaks down faster in hot weather.

How many nodules do my soybeans need?

Based upon data by John Heard, Soil Fertility Specialist with Manitoba Ag, you should have a minimum of 10 healthy nodules per plant for good yields. Research has show that soybeans with less than 5 healthy nodules per plant may benefit from an in-crop nitrogen application.

But I got no nodules!

When I worked in Ag Retail, there is usually one or two fields every year that either had an inoculation failure or were planted into virgin soybean ground. Invariably the question becomes, should I do an in-season rescue, and what rate should I use? Based upon data from John Heard of Manitoba Ag, he suggests the following. At a minimum you should apply 50 lbs of actual N/ac at podfill (R3-R4), but they did see economic response up to 100 lbs actual N in a relatively low yield environment (trial ran 31 to 41 bu/ac). Response is dependent on rainfall and soil moisture following application. John recommends minimizing leaf burn, as it will negate any benefit to doing the practice (use Urea or apply UAN without burn). My recommendation is to do a minimum of 75 lbs actual N/ac, as we are in a higher yield environment than Manitoba. Link to trial below; http://www.umanitoba.ca/faculties/afs/agronomists_conf/media/Heard_Rescue_N_applications_poster.pdf

I’m not a combine expert, but I know somebody who is.

Last week a reader commented that they use a chaff spreader and still have issues with volunteer wheat behind the combine. I asked combine expert, Marcel Kringe of Bushel Plus, for a few suggestions. He mentioned the following; 1) If losses are primarily from the rotor, it could be from one of two issues. A) the rotor isn’t spinning fast enough to force the grain out through the concaves, or, B) there isn’t enough room in the concaves for the volume of the material, and you may need to consider a different concave (with less wires). 2) You need to adjust combine settings based upon ground speed and crop conditions. What may work at 2 mph, will not work at 3 or 4 mph. More material may require more air, etc. 3) Not all combine chaff spreaders are created equal. There is a difference between brands as far as design and performance. If you have had your dealership’s combine expert out, and are still unsatisfied with its performance, it may be time to do a demo of another brand.

Measure combine performance in bushels per hour

Marcel Kringe of Bushel Plus commented, that in Australia, growers measure harvest performance in bushels per hour. In Marcel’s opinion these machines have such a high depreciation rate (per hour), that growers should be trying to cram as many bushels/hour through the machine as possible. If you are running your combine at less than full capacity, it costs both in lost time, and, a higher depreciation rate per bushel of grain harvested.

Pod and Stem Blight/Phomopsis Seed Decay in Soybeans

A brief overview of what I feel is underrated issue in Ontario soybeans. Pod and stem blight and Phomposis seed decay is caused by fungi in the Diaporthe genus. Disease infection is impacted by planting susceptible varieties, and greater than normal rainfall during the pod-filling stages (for Ontario, think summer/fall 2018).

Pod and stem blight present’s as raised specks in linear rows on mature soybean stems, resulting in premature death. The black spots may also appear on pods but may not follow the linear pattern found on the stem. The specks are most prevent from R6 (full seed) to R8 (full maturity). Yield losses result from in-complete seed fill caused by early plant death.

Phomopsis seed decay presents as cracked, shrived seed with white chalk-coloured mould on the seed surface. Diminished seed quality and reduced seed vigor, germination and emergence are all issues of Phomopsis seed decay. Seedings developing from infected seed having small reddish-brown lesions or streaks on the cotyledons or lower stems.

So what should I do? Plant non-susceptible cultivars and avoid infected seed, consider a fungicide labelled for control at the R3 to R5 stage, control velvetleaf and pigweed (hosts), and harvest timely. Pod and stem infections occur during the R5 to R6 growth stages, a fungicide applied at that time may reduce disease and improve seed quality, however, yield may not be affected. Seed production fields should be managed for this disease.

Registered products for this fungus include StrategoPro and Trivapro. US data supports Priaxor as a possible option, but in Canada it is not labelled at this time.

(Notes from Crop Protection Network Factsheet CPN-1007 and BASF)

Pod and Stem Blight/Phomopsis Seed Decay

CPN -1007 Factsheet

I’m at threshold for Western Bean Cutworm, which product should I use?

In my mind there are only two actives you would consider. Chlorantraniliprole, which is in Coragen, or Voliam Xpress (pre-mix of Coragen and Matador). And spinetoram, which is in Delegate. Which product you decide to use will depend on availability, ease of use, and past experience. Need more information on scouting or managing this pest? Contact us.

I have soybean aphids, what product should I spray?

I have yet to hear of soybean aphids at threshold, but eventually there is a chance a field will need to be sprayed. There are several options. The table below has a few of the highlights.

“We assume that persuasion is about talking, when actually the most persuasive strategy is listening.”

- Sheila Heen