Pre-harvest spraying

Farmers apply glyphosate at different points in the season, as our What is glyphosate? page explains. One of them is shortly before harvest. This page explains what pre-harvest application is, which crops and regions it applies to, where it is not allowed, and which foods those crops go into. It describes farm practice only. It does not say anything about any single product, and it makes no health claims.

What pre-harvest application is

• Timing. Pre-harvest glyphosate is applied late in the season, when the crop is nearly mature. In Canada, it was first registered in 1992 for pre-harvest use on wheat, barley, soybeans, peas, lentils, canola and flax. The label said to apply at 30% grain moisture or less, typically 7 to 14 days before harvest.¹

• Purpose, in each source's own words. Sources describe the purpose differently:

  • Canada's Keep it Clean program, run by the grain industry, says glyphosate is registered there for pre-harvest weed control only and "is not registered for use as a desiccant."²
  • University of Minnesota Extension describes applying glyphosate to wheat at the hard dough stage, with a seven-day pre-harvest interval.³
  • Washington State University lists glyphosate as a harvest aid in chickpea, dry pea and lentil.⁴
  • Michigan State University Extension describes glyphosate as a preharvest weed control option in dry beans, applied at the hard dough stage (30% moisture or less), with a seven-day preharvest interval.⁵

  We use each source's own term. We do not call every pre-harvest use "desiccation."

Crops and regions

Our spray calendar shows typical months for pre-harvest use, by crop and region, with a source for every row. In short:

Months are typical, not exact. The calendar explains how each row's months were set.

• Oats in Canada and the U.S. Keep it Clean says glyphosate is registered in Canada for pre-harvest weed control on oats, applied only once grain moisture is under 30% in the least mature part of the field.⁶ In the U.S., University of Minnesota Extension wrote in 2019 that, among the small grains it discussed, a pre-harvest glyphosate application "is only labeled in wheat."⁷
• Pulses in Canada. Keep it Clean's 2026 advisory says glyphosate is registered for pre-harvest weed control on chickpeas, lentils, peas and dry beans.⁶

Buyers set their own limits

Some grain and pulse buyers do not accept crops treated before harvest.

• Keep it Clean's 2026 advisory tells growers to consult their grain buyer first, because some buyers may not accept cereal crops treated pre-harvest.⁶
• The Prairie Oat Growers Association says oats "MAY NOT be accepted" if treated with pre-harvest glyphosate.⁸
• Manitoba Pulse & Soybean Growers says most bean dealers "no longer accept pre-harvest glyphosate on dry beans."⁹
• Washington State University notes that some pulse buyers will not purchase crops treated with it.⁴

The European Union does not permit pre-harvest desiccation

The European Commission says pre-harvest uses "for desiccation to control the time point of harvest or to optimise threshing are not permitted in the EU."¹⁰ Glyphosate itself remains approved in the EU until December 15, 2033, with conditions. See Where agencies stand.

Where these crops end up

These crops are ingredients in many everyday foods. This says where a crop goes. It does not say whether any given food has residue; for testing results, see What residue testing has found.

• Oats. The Northern Crops Institute says oats for human consumption are "primarily utilized as rolled oats and whole oat flour." It calls hot breakfast cereals the "premier use," with other uses including "cold cereals, bakery products, granola bars, and baby foods." It also notes that most U.S.-grown oats are used for animal feed.¹¹
• Wheat. USDA's Economic Research Service says hard red winter wheat "is principally used to make bread flour," soft red winter wheat flour "is used for cakes, cookies, and crackers," white wheat flour "is used for noodle products, crackers, cereals, and crusted white breads," and "Durum wheat is used in pasta production."¹²
• Pulses (dry peas, lentils, chickpeas, dry beans). USA Pulses, a U.S. industry group, says "Soup represents the most common use for food legumes." Its product manual also covers pulses in baked goods, snacks, cereal and energy bars, pasta and noodles, and baby and weaning foods.¹³

On ByeGly

ByeGly's guides cover these food categories and list products that carry Glyphosate Residue Free or BioChecked Non-Glyphosate certification. See the guides for oats, bread, flour, pasta, cereal and granola and beans and lentils. A product that is not on our list is simply not on our list.

Sources