Neonicotinoids and Field Crop Production in Ontario

History of Neonicotinoids in Field Crops

  • First registered on corn in 2001
  • Now: Corn 99%
    Soybeans 65%
    Cereals 25-33%
    Dry Beans 95%
    Canola 100%
  • Lower a.i. rate per acre, less labour intensive, lower grower exposure and in some cases, the most effective (and only) measure of control
  • Neonics are registered on all fields crops in Ontario except for forages

Rates of Seed Treatments on Field Crops

Crop Product* Rate
(grams a.i./acre)
Corn Poncho 600FS
Soybeans Cruiser 350FS
Canola Gaucho 480
Dry Beans Cruiser 5FS
Wheat Cruiser 5FS

*For simplicity, table shows only 1 neonic product per crop. Other products/actives are registered and used.

Crop Pest Acres at Risk Potential Yield Loss
10-20%, 40% (heavy)
10-20%, 40% (heavy)
Corn (seed, sweet, field)
2% to replant
corn rootworm
black cutworm
corn flea beetles
(seed & sweet)
*Stewarts Wilt
bean leaf beetle
5-13%, 40% (BPMV)
soybean aphids
seed corn maggot
Dry Beans
seed corn maggot
potato leafhopper
10-15%, 40% (heavy)
crucifer flea beetles

Corn Rootworm


  • Root feeding on corn grown after corn
  • 7.5% of acres at risk
  • Crop loss value of $29 million

Image of root feedong on corn

Assessing the Alternatives

  • Fields most at risk are corn on corn
  • Rootworm Bt corn generally more effective than insecticide options including neonics
  • Rootworm Bt hybrids available in virtually all cropping scenarios (except sweet corn)
  • Granular insecticide (Force 3G) still available for refuge (however significant costs incurred to equip planter ~15K for 12-row planter)
  • Crop Rotation

Crop Production Impacts without Neonics = Low

Bean Leaf Beetle


  • Can cause severe damage on seedlings and late season pod feeding
  • Vectors bean pod mottle virus – export concerns for food grade market.
  • 20% of acres at risk
  • Crop loss value $26 million

Image of bean leaf beetle causing damage on seedlings

Assessing the Alternatives

  • Can be scouted/somewhat predicted
  • Neonics provide superior protection (systemic) from virus vectoring which cause seed quality and export market concerns for food grade soys.
  • Neonics provide early season control reducing replanting and second generation pressure
  • Foliar application of non-neonics insecticides provide effective control of beetles but not on virus vectoring

Crop Production Impacts without Neonics = Medium

Flea Beetles in Canola


  • High infestations cause severe foliar damage and in some cases replanting is required
  • 65% of acreage at risk
  • Crop loss value of $6.3 million

Image of flea beetles causing sever foliar damage

Assessing the Alternatives

  • Neonic seed treatments provide four weeks of protection (= 1 to 2 foliar sprays)
  • Seedling stage is very susceptible and foliar applications offer short term protection (no residual)
  • 4 major pests require foliar applications each season
    Significant concerns over non-target insects
  • Very few chemical families registered to rotate with
  • All seed is treated in Western Canada. No facilities in Ontario to treat canola seed

Crop Production Impacts without Neonics = High

Other Concerns

  • Grubs (European chafer / June beetle) (multiple crops in soils for multiple years)
  • Wireworms (multiple crops for multiple years)
  • Leafhoppers on edible beans
  • Corn flea beetles (seed corn and sweet corn)
  • Seed corn maggot in soybeans and edible beans

For these insects, effective options are limited, costly or do not exist.

Significant implications to the hort crops, especially for soil pests (grubs and wireworms)

Use of Neonics in Field Crop Production: Two Main Issues

  • Insecticide Containment at Planting (acute risk)
    • Found to be linked to incidences
    • Fugitive dust from vacuum planters
    • Impacts of polymers and lubricants
    • Farmer practices
    • Environmental conditions

Opportunity to make a direct, positive influence on bee kill incidences

  • Total Insecticide Loading (chronic risk)
    • More science needed
    • Acres treated
    • Rates of active ingredient
    • Soil and water levels
    • Multiple exposure
    • Pollen level impacts

Containment at Planting

Image of planter

Image of planter

Ontario Acres Planted with Negative Vacuum Planters

Corn – 70%
Soybeans - 25%
Canola – 5%

Original OMAF and MRA Best Management Practices

  1. Strengthen communication with local beekeepers 
  2. Windy days in dry springs – plant in the early morning or evening
  3. Manage flowering weeds in & around fields before planting
  4. Minimize the amount of insecticide seed treatment used
  5. Limit the amount of seed lubricant (eg.Talc) used
  6. Exhaust dust towards the center of the field  
  7. Modifying planters with deflectors

BMP article: OMAF and MRA, Field Crop News, GFO and OBA Websites

Enhancements to BMP’;s for Fugitive Dust Containment

  1. Vacuuming/washing out planter often to reduce dust accumulation within manifolds
  2. Enlist industry to improve polymer coatings and reduce dust off risk
  3. Use lubricants with lower risk of abrasiveness and drift potential
  4. Increased education with respect to quantity of lubricant required.
  5. Improved planter options for dust containment
  6. Non-insecticide treated seed

Enhancements to BMP’;s for Fugitive Dust Containment

  • Map of hive locations to indicate fields of concern and way to contact beekeeper to let them know (frequent request from growers)
  • Avoid planting in fields directly next to hives on windy days

Tech Transfer Plan for BMP Education

  • Separate IPM infosheet/booklets identifying fields at high risk and how to scout for soil pest issues
  • Promote BMPs at significant winter grower events (Southwest Ag Conference, FarmSmart, Eastern Crops)
  • Partner with others to deliver common BMPs to growers (eg. PMRA, GFO)
  • Mass social media campaign during winter and early spring time

For more information:
Toll Free: 1-877-424-1300