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The Cropwalker - Volume 3 Issue 30

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Crop Conditions

Crop conditions Weather seems like most of Western Ontario got some rain last week anywhere from 1 to 5 inches. Probably some farms and areas are still dry. Central Ontario received some as did eastern Ontario. Quebec and Maritimes dry. There is/will be a forage shortage in these dry areas. Corn where there is rain the crop looks amazing. Continue to scout for diseases. Question How do I know if nitrogen is limiting my yield. Answer It is normal for some of the lower leaves turn colour in parts of fields such as high areas. If the ear leaf is green and hopefully the leaf below the ear is green, nitrogen is not limiting. It is normal for the plant to move nitrogen from lower leaves if there is not enough “available” nitrogen in the soil. One of the main reasons for nitrogen not being available is lack of soil moisture. Soybeans are generally R4-R5 (R4 pod ¾” long at one of the 4 uppermost nodes on the main stem, R5 is  seed 1/8” in size in a pod at one of the 4 uppermost nodes of the main stem) Insects spider mites continue (see below) Bean Leaf Beetle and Japanese beetle are evident by the leaf feeding. Normally if leaf feeding does not exceed 25% defoliation yield should not be affected.   Western Bean Cutworm peak flight has passed for most areas. In some areas where there were high numbers (moth count of 300 or more/trap) growers are deciding not to spray corn. They have already sprayed their fungicide. IF you have edible beans and have not sprayed for WBC Dr Christina DiFonzo from Michigan State University is suggesting growers spray for WBC if nearby traps have 300 moths or more. Forages depending on if you received rain yields are great to nothing. If you have alfalfa short and blooming clip it to remove the apical dominance of the plant. Otherwise the plant will keep building root reserves and try to set seed. If you want another cut or clip now.


Things to do this week

1.     Check cover crop. If for any reason it is not all emerging, reseed. Check for weeds.

2.    Plan next years crop rotations. Decide where you will plant wheat next year (2021) to decide on a soybean variety for that field.

3.    Do a corn yield estimate.

4.    Go over combine and get it ready for bean harvest. Once that is done, check the drill and get it ready if putting in winter wheat. If the opening blades were barely cutting corn stalks in the spring when drilling beans, it will not be cutting soybean residue.

5.    Review this year’s herbicide program to make changes for next year.

Western Bean Cutworm in Edible Beans

There is no easy way of managing this pest when we do not have effective tools to determine when to spray. Whatever decision you make will be wrong, so it is about picking the lesser of two evils that is less wrong, rather than the one that is right. If you have high trap counts in your area, strongly recommend using an edible bean product that provides both ovicidal and residual control. Essentially you are looking at products that contain Chlorantraniliprole (Coragen or Voliam Xpress). Delegate is a good option as well; suggested timing is to be used at or after egg hatch. My preference is to use something that can be used prior to egg hatch, has residual activity and controls the larvae. If you decide not to spray, you run the risk of having both yield loss and higher pick. Some growing edibles can stomach the thought of this and roll the dice, others will not be able to sleep at night knowing the bugs maybe eating their crop. Pick the management strategy that fits with the risk you can live with.

Spider Mites

They overwinter as eggs. In the summer they hatch and move to crops from permanent vegetation (generally field borders). They pass through 3 stages, egg larva and adult. It takes 5-19 days to complete a life cycle. Hotter temperatures tend to speed up the life cycle. Females can produce 100 eggs each. The eggs hatch on the underside of leaves. They produce a fine webbing that earns the name “spider” mite. They disperse by spinning a silk thread that is caught by the wind. There is no well-established time to quit spraying. However, rain encourages new growth to offset the feeding effects of spider mites. Wet weather encourages the buildup of diseases that control spider mites. Most fields are at R5 now (flowering complete, plant reached maximum height, small beans [0.3 cm] in top pods). Stress occurring during R4 to R6 can cause a yield loss. So, this week will probably be the last time that spraying would benefit soybeans.

Grow your own Oats

This is the 3rd year in a row that oats for cover crop is selling at $4-500.00 per tonne. You can expect to grow 1.5- 2 tonne per acre. Next spring consider planting a few acres of oats and using/selling for cover crop seeding.

Corn – Spraying for Western Bean Cutworm

There is a risk you will still have to spray for western bean cutworm. There is no rule book saying you will not have damage if they have not shown up prior to brown silk. Last year we saw moths lay eggs much later than expected (peak flight was later than expected). Keep checking.

Question – Which Corn Trait Control Western Bean Cutworm?

The only trait on the market that has activity is “Viptera” (event MIR 162). If you have hybrids with Viptera or Trecepta or Optimum Leptra, you will not have to spray for Western Bean Cutworm. At this time, the Herculex trait (SmartStax/Optimum AcreMax) is essentially considered in-effective on WBC.

Manage what you can for winter wheat yields.

I went through the historical Ontario Cereal Committee winter wheat trials (Area II) to check on the variation in thousand kernel weight and yield. As far as I can tell looking at the data, thousand kernel weight has less impact on final yield from year to year than heads per square foot or square meter. Outside of applying a fungicide application at heading, and maintaining strong fertility into grain fill, it is more critical to manage for optimal seeding date and population than it is for later season plant health. Figure out the right seeding rate, fertility, and proper drill setup to have the optimal plant stand, and then manage for grain fill the following year. As you are aware, we only get one shot to get the right plant stand.

Figure 1 - Winter Wheat TKW by Variety by Year for Area II OCCC Trials

Bulls and Bears of forecasting yield for 2020 for corn and soybeans

Figure 2 - Ontario Corn and Soybean Yield Thoughts

Boron – Alfalfa Response

Still amazed at the number of fields without boron as part of the alfalfa fertility program. If you are seeing the upper leaves of the plant look like the photo below, you may have boron deficiency. OMAFRA data suggests that you could have crop responses of up to 1100 lbs/ac additional forage on deficient fields. Applying boron can improve forage quality, mainly by preventing leaf loss, as the leaves dry much faster than the stem when deficiency is present. These plants will also have a reduction in winterhardiness. I have visually seen hill tops/upper slopes of hay fields with essentially no alfalfa, and a relatively lush stand on the remainder of the field, even with manure applied. Boron is a critical part of an alfalfa fertility program. It is likely too late to apply for this year but if you are seeing these symptoms, I encourage you to apply boron next year. I have read in a few publications that boron can help with winter survival but have not come across anything specific to boron and winter survival in the scientific literature. But common sense suggests a healthy plant will build more root reserves to get through winter. Lack of boron means smaller tops and roots.

Picture 1 - Boron Deficiency in Alfalfa

Estimating corn yield

Is rather simple. You calculate the number of kernels per acre and then estimate the weight per acre based on kernel number and you have yield. The standard number of kernels per bushel is 80,000. (80,000 kernels in a standard corn seed unit which at one time was a 56 lb. bushel) Usually when I do yield estimates, I figure it will take 90,000 kernels to make 56 pounds. It can be 75,000 to 100,000 kernels to make a 56-pound bushel. September weather dictates.

Test weight has nothing to do with final yield in Corn (or any crop for that matter)

Yes, I said it. Test weight does not matter when it comes to final yield, it is purely a grading factor. What does matter is “thousand kernel weight, or TKW). In corn this is accounted for when you must adjust on the number of kernels it takes to make 56 lbs of legally traded grain. (Technically 2204.6 lbs. in Canada since grain is legally sold by the Metric Tonne.)

Estimating the number of kernels per acre

This is where the biggest errors occur. The best method is to go to an area of the field where the yield is average. You can find this area by looking at previous yield maps or knowing your field. Measure 1/1000 of an acre. For 30” rows this is 17’ 5”. Then husk all the cobs in that 17’ 5”. Then either pull them all off or find 3 average size cobs. (This step is where most people go wrong. They figure if they have 29,000 plants, they have 29 cobs. Seldom occurs.) Then count the number of average size cobs. If there is a big variation in cob size this is complicated. It may take 3 smaller sized cobs to equate to 2 average size cobs. Once you have your average size cobs, count the number of rows (will always be an even number) and count the number of kernels per row. I normally stop about 1 inch from the tip. Now you have number of kernels per cob. Calculation is, kernels per cob X average sized cobs divided by 75 to 100. (This time of year start with 90. As the fall progresses, you may have to recalculate with a different number, or use a range to do the estimate, worse case 100, best case 80, most likely 90. Once you have the number of kernels, it is easy to do.) Say you have, 18 rows per cob and 32 kernels long, 27 average size cobs. It is 18 X 32 X 27 = 15,552. Divide this by 90 =172.8 bu/ac. If you divide by 100 because of smaller kernels it is 155 bu/ac. If crop is advanced relative to other years and has great plant health, divided by 80 = 194.4 bu/ac. Now you have a range for the field depending on fall weather conditions.

Wet Straw will Lead to Issues in 2021 planting if not managed properly

A client commented that depending on how wet straw is managed, it may lead to issues in 2021 planting if no-till or strip-till is the tillage system of choice. His suggestion is that if you do need to combine ahead of a rain event, spread the straw 20-30’ wide without using the chopper (depending on header width), and then rake it back up when ready to bale. It will dry faster and maintain better condition than trying to dry out a windrow that is 3-5’ wide and soaking wet.

Picture 2 - Wet Straw

Soil Sampling after Cereals?

One issue I wanted to point out is to soil sample both in and out of the straw row. How many cores you pull in the straw row will depend on header with of the combine. You could pull all cores out of the straw row if you wanted a worse case soil sample result for the field. This maybe be better in situations where minimal tillage is being done. Pulling all cores on from where straw has been laid, especially if it has been rained on, will artificially inflate field soil test values of K and possibly P.

Forage questions. We received more than normal number this year.

Question Can I under seed alfalfa next spring to my winter wheat.

Answer No wheat is too aggressive.

Question Will I get a crop to harvest this fall if I plant winter wheat or winter rye cereal now. Answer No Neither of these crops will go into the elongation stage. They will get 8-10” high. If you can harvest something that short you can do it and get another crop next spring.

Question Can I or should I do a mix of Winter Cereal Rye and Oats, and take a cut in the fall?

Answer If you want to plant a mix of Oats and Rye or Oats and Winter Triticale, ensure you cut high enough that the winter rye will survive. Most growth this fall will be from the oats.

Question I always seed with a brillion seeder. This year I did not get a catch. Why?

Answer Brillion seeders work if seeded and you get rain. This year when it turned dry the seed did not germinate or some did germinate and then when it turned dry, they died. I prefer a drill knowing some seed will be shallow and some down ½”.

Question How do I control volunteer cereal in my summer seeded alfalfa?

Answer A few herbicides you can use. I generally recommend Assure. Knowing it will kill grasses, so you must seed grasses after spraying with Assure. Wait 24 hours between spraying and seeding. I would not recommend using Venture L, as it does have some residual activity.

Question How late can I summer seed forages.

Answer The earlier you seed alfalfa after wheat harvest the better. If using Harvxtra or spraying Assure you can plant grasses later than alfalfa and expect to get a stand.

Question What can I spray alfalfa with to kill dandelions.?

Answer Do not waste your time doing this. You could kill the dandelions but still have a poor alfalfa stand. When you have a lot of dandelions it is time to terminate the alfalfa.

Is pelletized sludge a good soil amendment?

There are several sludge products on the market with a fertilizer license (no NASM plan required). Some products are either mixed with cement kiln dust (N-Viro), and/or are heat treated (Nutri-Pel, or LaSalle Agri Bio-Pellets), then dried and pelletized. The main difference between N-Viro and Nutri-Pel/Bio-Pellets, is that N-Viro contains some calcium and potash, whereas Nutri-Pel/Bio-Pellets have minimal calcium and potash, but higher amounts of nitrogen. All can be spread with a lime or manure spreader, then should be worked in to reduce smell and risk of off-site movement of phosphorus. To answer the title question, is pelletized sludge a good soil amendment? If you require phosphorus to either build up soil P levels or for crop response, it can be a very economical source of broadcast P. Continue to use a starter P depending on soil test levels, as environmental conditions can limit phosphorus availability in the spring. Please note, there are application rate limits on these products, especially those made from cement kiln dust.

Figure 3 - Pelletized Sludge Products in Ontario (as of 2019)

Field Demonstrations at Canada’s Digital Farm Show (last year Canada’s Outdoor Farm Show)

Planting soybeans into Corn stalks. We have planted an early corn hybrid and then desiccated it with Reglone. The field was then worked with conservation tillage. This is to try and simulate spring conditions. The equipment companies will be demonstrating equipment that will plant soybeans 1 ½” deep into these corn stalks.

Big balers we are demonstrating 4 brands of big balers: AGCO, Claas, Kubota, and John Deere. The features of each were different. John Deere had an Accumulator which carries 3 bales that you can unload at specific areas in the field, Kubota has their Fast Bale which allows you to wrap round bales on the go. Claas had a BIG baler that bales a lot of material in a short time, AGCO features automatic chain oilers and greasers, and a cam less pickup.

"I like watching my corn popping up in rows."

- Tim McGraw