About the MPSG Bean App

The Manitoba Pulse & Soybean Growers (MPSG) organization represents 3,800 farmers in Manitoba who grow soybeans, edible beans, peas and other pulses. MPSG’s mission is to provide research, production knowledge and market development support to Manitoba pulse and soybean farmers. This app is a production tool that delivers research results and resources directly into the hands of farmers and their agronomists, assisting them with production decisions.

The MPSG Bean App features six interactive tools. The Seeding Rate Calculator can be used to determine the economically optimum seeding rate for soybean. A soybean Plant Stand Assessor walks users through evaluating plant populations after seeding to see if their target plant stand has been reached. A soybean Growth Staging Guide provides a picture and description of each growth stage and can be used to ensure timely management decisions. The soybean Yield Estimator outlines the key parameters that contribute to grain yield, allowing users to estimate yield prior to harvest. The soybean Harvest Loss Assessor guides users in an exercise to quantify harvest losses at the header and behind the combine to identify settings that need adjustment. The White Mould Risk Assessment helps users understand the environment and management decisions affecting white mould development in edible beans.

MPSG does not validate results and takes no responsibility for the accuracy if these results. The MPSG Bean App was developed with assistance from MPSG Production Specialists. Funding for App developments was been provided in part by Growing Forward 2. For more information, visit www.manitobapulse.ca

Harvest Loss

Soybean harvest losses can occur at the header during gathering and behind the combine. It is estimated that 80% of harvest losses occur at the header, which can have a significant impact on net return. There are four types of header losses to watch for:





Step 1

To measure header losses, stop the combine and back up 15-20 feet. For losses behind the combine, simply stop the combine in a different sample area.

Step 2

Use a ft2 area to count soybean seed losses in at least four areas along the header or behind the combine.

Step 3

Record seed counts in the table below to determine yield loss.


Add Area

Seed Size




Total Harvest Losses

Average number of soybean seeds/ft2

Yield Loss
- bu/ac

Percentage of Yield Loss

It is recommended to target harvest losses of less than 5%.

Estimated Yield % of Harvest Loss

Seeds Size

Enter the seed size according to your variety (found on seed tag label) and environmental conditions. If you expect larger seeds due to good growing conditions, decrease value to 2400 seeds/lb (larger seed). If you expect smaller seeds due to poor growing conditions, increase value to 3200 seeds/lb (smaller seed).

General Harvest Loss Tips

  • Avoid harvesting soybeans at less than 13% moisture to avoid seed damage.
  • Direct combine soybeans with a flex header at 4 mph or less to minimize header losses. Headers equipped with an air reel can also reduce losses.
  • Lower the cutter bar within two inches of the ground to capture the lowest pods, preventing stubble losses.
  • Measure losses regularly during harvest to optimize combine settings. Make one adjustment at a time to achieve losses of less than 5% (2 bu/ac of a 40 bu/ac soybean crop).
  • Rule of thumb: 4 seeds/ft2 = 1 bu/ac

    Information on soybean harvest speed and air reel use is based on research conducted by the Prairie Agricultural Machinery Institute (PAMI) in Manitoba.