Soil Quality

Good soil health makes economic and environmental sense. Soil erosion and salt buildup must be prevented. The following are considered good soil management practices.

Avoid Summerfallow

Continuous cropping makes more efficient use of water and significantly reduces the chance of soil erosion and salinity.

Rotate Crops

Alternate cereals like wheat with annual legumes like peas or lentils and other broadleaf crops such as canola. Perennial forage crops such as alfalfa can greatly improve soil health.

Use Reduced or Zero Tillage

Zero tillage (or direct seeding) involves the planting of a crop into untilled stubble of a previous crop. This system uses crop rotation and herbicides to control weeds. All crops except tuber and root crops can be produced in this fashion. Zero tillage eliminates soil erosion, saves moisture, and reduces fuel, labor and maintenance costs. Zero tillage can be practised on all soil types. However, wet, heavy clays are more difficult to manage without tillage.

Zero tillage crop production systems are designed around the following operations.

1. Crop Rotation – Crops with different characteristics should be grown. Alternate high residue - producing crops such as wheat, barley, corn and oats with low-residue producing crops such as lentils, dry beans, flax and buckwheat. Grow winter wheat or fall rye to improve weed management. Rotate cereal and broadleaf crops to manage disease.

2. Crop Residue Management – Straw and chaff must be chopped and evenly spread during harvest, or baled after harvest, to allow for proper seeding. Stubble height should not exceed the row width of the seeder. A chaff spreader should be added to the combine. Chaff can also be collected and fed to livestock.

3. Weed Control – Use crop rotation as much as possible to help manage weeds. In addition, a non-selective herbicide is used to control weeds before seeding, between seeding and crop emergence, pre-harvest and after harvest. Winter annual weeds (stinkweed, shepherd’s purse and flixweed) are best controlled in the fall with herbicides. Perennial weeds (quackgrass, Canada thistle) are best controlled by pre-harvest or fall application of registered herbicides. In-crop herbicides can be used as a follow up. All herbicides should be rotated according to their mode of action to avoid the development of weed resistance.

4. Fertility – Use a soil test to accurately determine fertility requirements. Moisture savings from zero tillage can result in increased yield, so the higher recommended rates of fertilizer may be needed to optimize fertilizer use. Depending on seeding equipment, fertilizers may be applied at the time of seeding in the seed row or in a band alongside the seed row. There are limits to the amount of fertilizer that can be applied in the seed row without injuring the crop. Do not apply anhydrous ammonia directly to the seed row. Fertilizer can also be banded in a separate operation to maximize crop safety. Use low-disturbance banding equipment such as knives or spoke injectors. Ammonium nitrate can be broadcast-applied, but this method is not recommended for urea-based fertilizers as nutrient losses can be substantial.

5. Seed Placement – With good residue management, seed drills and air seeders designed for zero tillage give excellent seed placement. Seed should be placed more shallow than in tilled seed beds (1.0 to 1.5 inches). At these depths, moisture and temperatures are sufficient to allow gemination. Seeding too deep delays crop emergence. On-row packing improves seed-soil contact and improves crop establishment.

Reduced tillage refers to the least amount of tillage required to create a good seed bed. This tillage system leaves sufficient ground cover (50 per cent on clays and silts, 65-75 per cent on sandy loams and sands) to prevent soil erosion throughout the period when no crop is growing. Adequate trash cover is best achieved by eliminating fall tillage and, instead, controlling weeds with a late fall application of a registered herbicide.

There are numerous options for reduced tillage, depending on the tillage equipment available.

The amount of residue remaining increases with decreased depth and lower tillage speed. Tillage after low-residue crops such as lentils and field beans should be avoided or limited to one pass.

Use Shelterbelts and Cover Crops

Especially where potatoes or vegetable crops are grown, plant permanent shelterbelts and sow fall cover crops such as fall rye after harvest.

Table 1 - Crop residue left after different implement operations

Crop residue left after each implement operation
Tillage Implement	Per cent crop residue
Wide blade cultivator (36" blades)	90
Rod weeder	90
Field cultivator (9-12" sweeps)	80
Field cultivator with harrows	60
HD cultivator (16-18" sweeps)	75
HD cultivator with rodweeder	80
HD cultivator with harrows	60
One-way disc	50
Tandem disc-offset disc	50
Moldboared plow	10
Disc drill	85
Hoe drill	80
Air seeder, shovel openers	80
Air seeder, knife openers	90
Air seeder, harrows/packers	60
Fertilizer injector	85
Harrows	90
Coil packer	95
Tine harrows and packer	85

Avoid Burning Stubble

Provincial regulations control when stubble burning is permitted based on weather conditions. Managing straw, using tillage, harrowing or baling, is preferred over burning.

Keep Natural Wetlands

Draining wetlands removes important habitat and alters natural drainage patterns. Often, drained soil becomes too saline to support crop production.

General Information on Crop Production | Organic Crop Production Basics | Soil Quality

For further information, contact your GO representative.