Ontario Field Crop Report
2006 Soybean Crop Seasonal Summary

Table of Contents

  1. Summary
  2. Planting
  3. Growing Season
  4. Soybean Insects
  5. Harvest
  6. Production Challenges for 2007

Technical information can be obtained at the OMAFRA Field Crops Webpage and Crop Pest Ontario. Referenced OMAFRA Publications include the Agronomy Guide for Field Crops (Publication 811), the Field Crop Protection Guide (Publication 812), Guide to Weed Control (Publication 75), and Ontario Weeds (Publication 505). These can be obtained from your OMAFRA Resource Centre, or by calling 1-800-668-9938.


The 2006 overall provincial yield average will be a record high. Some producers have harvested their highest soybeans yields ever this year. With 30% of soybean yields reported the provincial average to date is 48 bu/ac. Last year's record setting yield was 41.5 bu/ac. Although overall seed size and quality was normal, there was considerably more phomopsis seed decay, downy mildew and weathering of seed than normal. Some producers lost Identity Preserved (IP) premiums because of reduced seed quality. Despite the wet fall, overall seed size, colour, and quality have held up well.


Excellent early spring weather and good soil conditions resulted in an early start to soybean planting. Approximately 30% of Ontario acreage was planted between May 1st and May 10th. Rain which started on May 11th, halted planting progress until May 22nd in southwestern Ontario. Planting resumed in late May with most producers finishing their planting by the end of May. Due to the cold, wet conditions that started May 11th, a considerable amount of replant was necessary especially on heavy clay soils. About 5% of the Ontario crop was replanted due to poor emergence and these replanted fields emerged well. Beans planted after May 22nd took advantage of excellent soil and weather conditions for quick emergence and a good start to the growing season.

Growing Season

Soybeans have incredible yield potential given the right amount of heat (Crop Heat Units) and rainfall. Soybeans are well known to respond to timely rainfall especially during July and August. The 2006 growing season was above average for Crop Heat Units (CHU) and precipitation. From May 1st to August 31st weather stations across Ontario recorded an average of 75 CHU's more than the 30 year average. Timely rains, during July and August, resulted in excellent pod set and good seed size. Most areas received significantly more rain in 2006 compared to 2005 during the May 1st to August 31st period.

Soybean Insects

Bean leaf beetle pressure was high this spring and late summer. Some areas in Essex and Kent needed foliar insecticide application to control this pest. Leaf feeding (below economic thresholds) was evident in many fields west of Toronto and as far north as Grey County. Late season economic thresholds were reached in localized areas as far north as Huron County. Bean leaf beetles have not been a problem this far north in previous years. This pest will require close scrutiny in 2007 and control measures taken once economic thresholds are reached.

Soybean aphids populations were observed in southwestern Ontario, but fields stayed well below economic thresholds. Aphid numbers were higher in eastern Ontario with some fields almost reaching threshold by late in the season. However, aphid populations fell in late August so no fields were sprayed in the province. The soybean aphid spray threshold is based on observing 250 aphids per plant with increasing aphid populations.


Harvest was frustrated by excessive rainfall and cloudy weather during most of the September through November period. The 2006 harvest season was the wettest and cloudiest in recent memory. As of December 1st, approximately 5-10% of the crop has still not been harvested due to wet conditions.

Production Challenges for 2007

Increased Acreage

Wet weather has significantly reduced winter wheat acreage planting intentions. Some of those intended wheat acres will likely be planted back into soybeans and this lack of rotation may increase disease and insect pressure in 2007. Soybean cyst nematode (SCN) is present in counties as far east as Brant and Peel, and as far north as Bruce. Growers in these areas will need to minimize the impact and spread of this pest through good management practices. Growing susceptible varieties back to back will increase SCN populations in affected fields and greatly reduce yields. Monitoring individual fields for this pest will be important next season so that the right management decisions can be implemented in coming years.

Soil Compaction

Many fields were harvested under wet soil conditions this fall resulting in ruts and other damage. Many producers turned back to the plow to level ruts and help reduce compaction. More tillage increases costs, soil erosion, and decrease overall soil health. Compaction is likely to be evident in 2007 and management decisions should be implemented to reduce other stresses which may over emphasize the compaction effects.

Soybean Rust

Soybean rust was not found in Ontario in 2006. Soybean rust did, however, move further north in the United States, especially late this fall. Currently, rust has infected soybeans in 231 different counties in 15 states, the most northern infection being reported in LaFayette, Indiana. Increased soybean and host plant infection will result in more spore formation. Close monitoring of this disease is essential. Ontario will need to be vigilant in 2007 to monitor the spread of rust, and be prepared to apply control measures if necessary.

For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca