Controlling Weeds

Weeds will normally cause some yield-loss in organic crops and this is accounted for in long-term average organic yields and organic premium rates.

When calculating penalties for weed-related yield losses, the average percentage of loss due to weeds is deducted from the penalty.

If weed populations reduce your yield enough to put the crop in a claim situation, SCIC will evaluate your organic weed management practices. If weed management practices are considered inadequate, penalties may be applied based on the yield-loss attributed to the weeds. In this situation, the portion of the claim resulting from inadequate weed control will not be paid.

To evaluate whether weed management is adequate, SCIC will evaluate the following:

• Crop rotation

• Frequency of green manure plow-downs and summerfallow

• Use of perennial crop phases in rotations

• Use of diverse crop types and seeding dates (e.g. fall cereals, spring cereals, oilseeds, pulses, forages, green manures)

• Rotation of highly competitive crops with less competitive crops

• Use of competitive crop cultivars (e.g. taller varieties as opposed to semi-dwarf varieties)

• Use of increased seeding rates, narrow plant row spacing and wider seed spread

• Appropriate use of delayed or early seeding, depending on primary weed pressures

• Proper seedbed weed control, including use of false seedbed techniques

• Use of tillage (pre-seeding, pre-emergent, post‑emergent, post-harvest, inter-row)

• Proper prevention of weed seed set in plow-down and fallow years

• Other longer-term weed control such as mowing perennial weeds, clipping weeds above or within the crop canopy and chaff collection

When considering weed management practices, SCIC recognizes that not all of these techniques are appropriate for every farm, crop or year.