2021 Soybean Seasonal Summary

Soybean Field

Despite significant challenges including a prolonged wet fall, the average Ontario soybean crop was the highest on record. The average 2021 soybean yield sits at 51.6 bu/ac with 2.9 million soybean acres seeded. 2018 was the second-best year on record at 51.4 bu/ac. The 5-year average for Ontario is now 49 bu/ac. For comparison the US national 5-year average is 50 bu/ac and the Brazilian 5-year average is 52 bu/ac. Although not all regions had good yields, some fields in the southwest harvested incredible soybeans.

For the first time a variety performance trial at Ridgetown College averaged 100 bu/ac. This speaks to the success of modern soybean breeding. For variety information, see the Ontario Soybean Performance trials at gosoy.ca. Other areas were dry during summer or suffered from excessive rainfall events lowering yield. Some growers, especially on clay soils, have not been able to finish harvest so it was certainly not a good year for everyone. Both seed quality and yield dropped sharply for those beans that remained in the field during November and December rains. Seed beans that were harvested late this fall must be carefully assessed for both germination and vigor. Overall, strong prices and excellent yields were achieved by many Ontario soybean growers making 2021 a good year for soybeans in Ontario.

Spring Planting

A small percentage of the crop was planted in April, but many soybeans were planted in the typical mid-May planting window. There has been a trend in Ontario for some growers to plant soybeans before corn. Although planting early often produces higher soybean yields, recent Ontario trials have shown that ultra-early planted soybeans do not necessarily yield better than May planted soybeans. June planted beans usually yield significantly less (See Table 1.).

Table 1. Soybean Plant Stands at Yields (plants/ac X 1000)

 Planted April 22-26Planted May 18-22Planted June 7-10
Plant Stand (plants/ac X 1000)126134152
Yield (bu/ac)61.964.755.1
2020-2021 Ontario trials. Planted in 15” rows at 161 000 seeds per acre.

Soybean Cyst Nematode

Soybean Cyst Nematode (SCN) is the most important yield reducing soybean pest in Ontario. It was first identified in southwestern Ontario in 1988 and has now spread across the province. Many growers still consider SCN to be a problem isolated to southwestern counties, but this is no longer the case. High levels are now present in such places like Bruce and Wellington counties, as well as eastern Ontario.

Every Ontario soybean grower, regardless of where they farm, should assess their fields for SCN through soil testing. If SCN is detected, appropriate management strategies can be undertaken to limit yield losses. Yield reductions of up to 40% may be present without any obvious above ground symptoms. If a field has high SCN numbers and no management is undertaken, yield losses can be as high as 80% or more (see Figure 1.).

Figure 1. Severe SCN damage to a field planted with a non-resistant variety in Bruce county.

The Ontario Ministry of Agriculture, Food and Rural Affairs through Albert Tenuta (Field Crop Pathologist) and Katie Goldenhar (Horticultural Crop Pathologist) are coordinating a nematode survey, targeting field crop and horticultural crop fields across the province. The primary objective of this new 2-year CAP funded project is to update provincial nematode distribution maps as well as establish baseline data, for various nematode species including soybean cyst nematode, root lesion or other nematode species. These results will support the enhancement of current nematode Best Management Practices for field and horticultural crop farmers, helping to improve the economic and sustainability of crop production in Ontario. If you would like to participate (no charge) or need more information on the Nematode Survey, please contact Albert (albert.tenuta@ontario.ca) or Katie (katie.goldenhar@ontario.ca).

Nutrient Deficiencies

Excess rainfall turned fields yellow in early July. The fact that tile runs were so evident in water-logged fields was clear evidence that this problem was caused by a nitrogen deficiency (see Figure .2). Another factor that added to this N deficiency is that soybeans were in their rapid growth phase, attempting to quickly put on tri-foliates while flowering was in full swing. This rapid growth requires a lot of nitrogen.

Figure 2. Tile run soybean due to nitrogen deficiency. (July 7,2021)

Early season dry conditions also inhibited nodulation, so several factors came together to cause these symptoms: a large demand for N, limited available soil N due to excess moisture, and insufficient biological N fixation. Fields that were well drained and did not suffer from further heavy rainfall events recovered nicely, as can be seen (see Figure .3). In season nitrogen fertilizer application did not provide enough yield to cover the cost of the fertilizer.

Figure 3. Same field as Figure .2, but the plants have turned dark green. (July 21,2021)

Potassium (K) deficiency was widespread again this year. K deficient leaves turn yellow along the leaf margins. A soil test is the only reliable way to know if a field is truly low in K or only showing stress-induced K deficiencies. It’s also important to note that K deficiency symptoms may indicate soybean cyst nematode (SCN) feeding on the roots. Spring fertilizer application when soil tests are insufficient often provide a 4-5 bu/ac yield response (See Table 2.)

Table .2. Soybean Yield Response to Spring Applied Fertilizer

 Yield (bu/ac)Advantage (bu/ac)
Untreated Check57.5 
Aspire (100 lbs/ac)61.94.4
Aspire (83 lbs/ac) + KMag (45 lbs/ac) + MESZ (100 lbs/ac)62.55.0
8 Ontario trials in 2020-2021. Average soil test = 17 ppm for P, 126 ppm K. Aspire = 0-0-58-0.5B, K Mag = 0-0-22-10.8Mg-22S, MESZ = 12-40-0-10S-1Z


September harvest progressed well for early maturing varieties, and some growers managed to finish their entire crop by the beginning of October. But just as harvest was getting into full swing, rains started and persisted well into November. It was a difficult harvest, as can be seen (see Figure .4). Although standing plants can tolerate significant rains once they are mature, they quickly collapse under the weight of snow. Prolonged rainfall evens also reduced seed quality, so seed beans must be carefully assessed for germination and vigour both now and next spring.  

Since prices remain strong, yields were excellent, and winter wheat planting was lower, its likely that 2022 will see increased soybean acreage.  

Figure 4. Field rutting has increased the necessity of tillage this fall.