Field Observations
FALL 2025
October 9, 2025
October is here, a favourite month for many, as temperatures drop and fall colours abound. Soybean harvest continues, as does winter wheat planting, with corn harvest just around the corner for some.
Corn
Corn harvest will be approaching quickly for some, and has just slightly begun for other areas, as warm, dry weather has helped move along grain fill and dry down. Most of the corn will have reached black layer (physiological maturity) by this point in the season, with kernels now drying down to a harvestable moisture. Moisture content at black layer averages around 32 per cent. Grain dry down can be influenced by the tightness of the husk, the thickness of the outer portion of the grain (pericarp thickness), along with temperature and weather conditions.
Areas of northern Ontario have reported corn damaged by frost, in some cases prior to black layer, which can impact the quality and moisture of that corn.
As harvest approaches and begins, when out checking corn fields for moisture levels, make sure to look at stalk quality. A great way to do this is to push the corn stalk to a 45-degree angle. If it comes back up, great; if the stalk collapses and stays bent, target that field for early harvest. Another option is to kick the lower portion of the stalk, but do this carefully and only when wearing steel-toed boots. If it breaks, target for early harvest as well, but usually, as you walk through the field, you will get the clues if stalks are breaking when you cross over the rows. Stalk rots are a common culprit for poor stalk strength as well as plant cannibalization from leaf diseases, drought or nutrient deficiencies. Empty stalks leave no cellular structure to hold the plant up, and stalk collapse is inevitable once the winds come in. More on stalk integrity here.
Although these might not be as prevalent this year due to low moisture conditions, it is still important to be aware of stalk rots. Anthracnose is a dominant stalk rot disease that attacks the roots and stalks of plants that may have already shown some leaf disease. Spores from this fungus can remain alive for many years. When rain splashes the spores onto the lower stalk area, it makes shiny black spots, and then the stalks become black inside, rot, and fall over. Gibberella and Fusarium stalk rots are also caused by fungi that can live in the soil for many years. If the stalk is cut open with a knife (use caution when using knives), the inside of the stalk may have a pinkish colour, indicating that Fusarium and Gibberella may be present in the stalk. Many fields may be one strong windstorm from lodging.
The Ontario Grain Corn Ear Mould and Deoxynivalenol (DON) Mycotoxin Survey was conducted over the past couple of weeks. Grain corn samples are currently being analyzed for DON levels at the lab. A report from the surveyed fields will be available in the upcoming weeks.
Refresh your grain bin safety knowledge by listening to Grain Farmers of Ontario’s GrainTALK: Grain Bin Safety webinar. It is 30 minutes long and could save your life.
Soybeans
The past week has again seen incredible harvest conditions. Field Progress reports that 77 per cent of the soybean harvest has been completed, as of October 8, 2025.
Yields in some fields are below average, where moisture was limited, with others around average. With sunny, dry days, soybean harvest moisture has also been on the lower end of what some may prefer, with some fields coming off at eight per cent moisture.
There has been some discussion on whether it is a good idea to pause soybean harvest and wait for harvest moistures to increase after a rain. The general consensus is to continue with harvest, as the good weather window could change at any point, and getting winter wheat planted timely and into good conditions is also a key consideration.
Pay particular attention to weed escapes that are being found in soybean fields at harvest, to better prepare for next year’s herbicide decisions. If there are weeds of concern that are challenging to identify, consider getting them identified by a local agronomist or connect with Mike Cowbrough, weed specialist, OMAFA. Some fall management tips were also shared in the past, from OMAFA, and can again be found here.
Cereals
Field Progress reports winter wheat planting at 78 per cent complete, as of October 8, 2025. Now that the calendar has flipped to October, the winter wheat planting window has closed or is closing very quickly across the province. If planting past the optimum planting date, increase the rate by 100,000 seeds per acre per week. Optimum planting dates for winter wheat can be found here.
Agricorp planting deadlines for fall-seeded grains can be found here.
The deadline to submit yields for spring grains and spring wheat is October 31, 2025.
October 2, 2025
Another beautiful week, weather-wise, allowed many to start or continue soybean harvest. Winter wheat planting is also continuing.
Corn
Corn in some regions has reached black layer, while in other areas, it is in a later stage of grain fill.
For fields that still had green leaves in the past few weeks, the plants were able to fill the kernel completely, adding test weight. Plants that have turned brown may have succumbed to an early death due to drought and heat stress. These fields will need to be monitored and evaluated for harvestability and early stalk lodging.
Complete a stalk strength test by pinching, bending, pushing, or kicking the stalk; all forms of stalk testing are good. If stalks break easily with the push test, schedule these for an earlier harvest, as winds in the fall will make these fields prone to lodging, and field grain losses will be greater—more on stalk integrity in this Grain Farmers of Ontario factsheet.
As many approach corn harvest, if you have concerns about potential DON testing, check with your local elevator to learn how they conduct their DON sampling procedures. DON levels in many areas are likely to be at low levels this year; however, it can still be present in some hotspots where weather conditions were ideal for Fusarium development. Ideal sampling at elevators involves taking a two-kilogram corn sample to grind and then pulling a homogenized subsample of the ground corn to run the Eliza test (dip test). To learn more about the ideal testing procedure, watch here.
Soybeans
Late last week, soybean harvest was occurring across much of the province. Field Progress reports that 39 per cent of harvest is complete as of October 1, 2025.
Moisture ranges have been anywhere from nine to 16 per cent, recent rains helped bring moistures up, which was appreciated. Yields range from below 20 to above 70 bushels per acre on excellent ground that received timely rains. Some farmers have been surprised at how low seed moistures are this fall as the soybean plant had just matured with lower leaves still attached. Higher temperatures and dry weather have led to quicker seed maturity and drydown, resulting in earlier full plant death this month.
When soybeans are under 13 per cent, elevators don’t adjust the weight up for dry soybeans, so shipping too dry soybeans is like giving a percentage of your beans away for free. Even paying a little for drying charges and taking a bit of shrink for wet soybeans just to get them off the field and into the bin is always worth it compared to the weight lost from dry soybeans and a delayed harvest. Additionally, future weather predictions are sometimes incorrect for clear days to harvest, so waiting for perfect moisture at 13 per cent will not be feasible on many fields. By getting the soybeans off the field in a timely manner, it also allows wheat to be planted in close to ideal conditions without ending up mucking in the seed later in cooler conditions when seasonal weather occurs.
As harvest continues, residue management is key for optimum seedbed prep for winter wheat. More from OMAFA here on soybean residue management.
Another thing to consider is safety, along with mental health, throughout the harvest season. Giving a little extra room for harvest and planting allows for less stress to be put on farmers and employees, with more flexibility and the potential for more sleep. Working while overly tired is as dangerous as impaired driving.
Cereals
Field Progress reports that winter wheat planting is at 34 per cent complete as of Wednesday, October 1, 2025
The winter wheat that has been planted has gone into near-ideal conditions, with warm soil temperatures and good soil moisture, which has helped germinate the seed.
If planting much earlier than the optimum planting date, backing off on the population is advised, as good plant growth and tillering can be expected with the warmer fall predicted. If planting at ideal dates, the population should be at normal levels. Later planting dates will require higher populations to compensate for reduced plant growth and fewer tillers. Planting populations range from 1.2 million to 1.8 million seeds per acre, depending on the planting time, soil type, and management practices. Always verify your seed source and adjust the population according to the tested germination rate. If planting by pounds per acre, as that is how the drill is set up, ensure you check the seed size and adjust the number of pounds you are seeding accordingly. Based on the variety and environment in which the seed was grown, seed lots can vary by up to 3,000 seeds per pound. If seeding 103 pounds to the acre, this could mean a difference of close to 400,000 seeds per acre. Which, in turn, could mean a too-thin stand or a way too thick stand that may be more prone to disease and lodging. Be sure to adjust the planter.
Spring cereal harvest according to Field Progress reports that harvest is 100 per cent complete.
Environmental Farm Plan
The 5th edition of the Environmental Farm Plan (EFP) is now available. The updated edition incorporates current regulatory requirements and the latest scientific findings on BMPS. 4th edition EFPs will be accepted for Sustainable Canadian Agricultural Partnership (SCAP) until March 2028. Other organizations may request a more current EFP to support their compliance and/or funding programs.
Grain Farmers of Ontario recently launched Field Progress—your go-to source for weekly estimation on planting and harvest progress across the province, by district.
Right now, you’ll find the latest for soybean harvest and winter wheat planting progress.
And as the season rolls on, Field Progress will spotlight corn harvest progress—with spring planting updates coming next year!
September 25, 2025
As a new season arrived, so did a much-needed rain for the vast majority of southern Ontario. The corn milk line is progressing towards black layer, while the soybean harvest has had a strong start, as has winter wheat planting.
Corn
Corn milk line progression is between ½ and 7/8 milk line. The warmth of the past week really helped milk line progression move along. Black layer will be reached in the coming days for some hybrids.
Silage harvest is ongoing. Remember, silo gas with silage harvest can be a significant concern, especially in drought-stricken areas. For more information on risks and management from OMAFA, please visit here.
Soybeans
The soybean harvest rolls on with as close to perfect weather as anyone could ask for, up until Sunday night—sunny, warm days followed by a well-timed rain. The rain will help even out mature soybean fields and raise the seed moisture in areas that experienced early maturity within fields. Field Progress shares that the soybean harvest is at 20 per cent complete, as of Wednesday, September 24, 2025.
As soybean fields are harvested, it is a great time to test them for Soybean Cyst Nematode levels. Sampling is an important part of managing the pest, along with variety choice and crop rotation to a non-host crop. Ideally, fields should be sampled every 3 years. More on sampling and the implications of SCN on soybeans can be found here.
Are there suspicious weeds being found in soybean fields? A good first step is to consult with a local agronomist to help identify the weed and determine its potential causes.
For further insight, two testing services are available in Ontario to determine if plants are herbicide-resistant.
Plant bioassay testing by the University of Guelph– This service is offered through the University of Guelph, and requests mature seed collected in the fall to be submitted. Due to the seeds required, this is a great option later in the fall if plants have been frost-damaged but have viable seeds. Plants are then grown from the seed and sprayed with various doses of the herbicide(s) that are suspected to be resistant to. Results are typically provided by April. The service is provided at no cost to Ontario farmers.
Molecular testing by TurnKey Genomics (private lab) – The molecular testing service requires plant tissue that is roughly “loonie-sized”, so a single leaf is often adequate. Results are shared in a matter of days. Grain Farmers of Ontario helps fund some of this testing through OMAFA.
With respect to perennial weeds, there is an excellent article from OMAFA on fall herbicide applications and maximizing the impact on perennial weeds shared here.
Cereals
According to Field Progress, the spring cereal harvest is 91 per cent as of September 25, 2025. Winter wheat planting is at 13 per cent as of September 25, 2025. A well-timed rain this past week has helped any wheat that is in the ground germinate.
Mental health
As the fall arrives, take time to celebrate successes, whether big or small. Harvest is a stressful time of year. Be sure to take the time to get the support needed. Several support resources are available here.
