Manitoba
Printer Friendly

Manitoba Agriculture, Food and Rural Initiatives

Winter Wheat - Production and Management

 Articles:
Spring Germinating Winter Wheat
Preparing for Next Year's Winter Wheat Crop

Winter Wheat

Field Selection

Winter wheat must be sown into standing stubble to ensure successful overwintering of the crop. Avoid conflict with the harvest of spring-sown crops by growing an early-maturing spring crop in the field in which you intend to sow winter wheat. Canola stubble is preferred but barley and oat stubble are also suitable.

Do not sow winter wheat after spring crops that have poor snow trapping ability such as field beans, lentils, potatoes and field peas. Avoid seeding into wheat stubble. Straw and chaff from the spring crop must be uniformly spread to facilitate zero-till seeding.

Variety Information

Performance Testing

Variety Performance, Acreage, Seeding Date and Crop Rotation Effects on Yield

Seeding Winter Wheat

Treatments

To prevent seed and seedling rots/blight and common bunt, seed should be treated with a fungicide.

Additional Resources: Effect of Seed Treatment on Stand Establishment and Yield in Winter Wheat

Dates

September 1 to 15 in northern areas. September 1 to 21 in southern areas. Successful overwintering of seedlings requires that the crop be given adequate time in the fall to develop healthy crowns and at least two to three leaves. Temperature and time have a greater influence on winter wheat establishment than soil moisture. Therefore, seed on the optimum date regardless of soil moisture conditions.

Rates

1.5 to 2.5 bu/acre to achieve a target plant population of 20-30 plants/ft2 .

Grain yield in winter wheat is determined by the number of heads the crop produces. Row spacing should allow effective trash clearance by zero-till seeding equipment.

Seeding Depth

3/4 to 1 inch.

The minimum soil moisture required for germination is quite low and increasing seeding depth to reach moisture may result only in delayed emergence and reduced winter survival. Seed at the prescribed depth regardless of soil moisture.

Additional Resources: Winter Wheat Must be Seeded on Time

 

Fertilizer Requirements for Winter Wheat

General

For specific recommendations, have your soil tested. If soil analyses are not available, a general recommendation is as follows:

Nitrogen (N):

80-120 lb/acre N. These rates are required to maximize the yield potential of winter wheat while maintaining grain protein content. Broadcast ammonium nitrate (34-0-0) in the spring as soon as field conditions allow machinery to travel. Delayed applications result in reduced yield. Broadcasting nitrogen fertilizers such as urea (46-0-0) or urea-ammonium nitrate solution may result in reduced yield due to losses of N through volatilization, especially under warm, dry conditions.

Urea ammonium nitrate (UAN) solutions perform best in a surface or dribble band application. Treating urea with an urease inhibitor will delay volatilization losses for up to 14 days.

Phosphate (P2O5):

30-40 lb/acre. Place all phosphorous in the seed row. Inadequate phosphorus levels can hamper seedling growth and reduce winter survival potential.

Potassium (K2O):

On sandy textured or organic soils, apply potassium at rates of 15-30 lb/acre.

Sulphur (S):

Low sulphur levels can occur in any Manitoba soils. When required, apply 15 lb/acre of sulphate sulphur.

Further information on Fertilizer use in Manitoba

Special considerations

Field operations that break down stubble, such as fall banding of fertilizer, reduce the snow trapping potential of a field and increase the risk of winter damage. Placing more than 30 lb/acre of N fertilizer in the seed row may hamper seedling development, which also increases the risk of winter damage.

Weed Control

Since fall tillage is not an option, fields infested with perennial grass weeds, such as quackgrass, should be avoided. Control of winter annual weeds, such as stinkweed, shepherd’s purse, flixweed and narrow-leaved hawk’s beard, is particularly important in winter wheat. Best control of winter annual weeds with herbicides is achieved in the fall after the weeds have germinated and right before freeze-up. They may also be treated the following spring, but must be sprayed before the weeds bolt, which occurs in late April or early May.

Winter wheat is a competitive crop that can choke out many weeds, particularly summer annual weeds in the spring.

Insects

Aphids, wheat curl mite (which spreads wheat streak mosaic virus), wheat stem sawfly, wheat stem maggot and hessian fly can damage winter wheat.  Currently registered winter wheat varieties have low levels of resistance to insect pests.

 

Diseases Affecting Winter Wheat

Diseases of economic importance to winter wheat include leaf spots caused by Septoria species, tan spot, powdery mildew, stem and leaf rust, take-all, snow mould, barley yellow dwarf virus, fusarium head blight and wheat-streak mosaic virus. Currently registered winter wheat varieties have low levels of resistance to plant disease. Therefore, crop rotation and the use of fungicides are important management considerations.

To reduce the incidence of many diseases, avoid planting winter wheat on wheat stubble. Rust, however, is carried in by wind and its arrival differs from year to year. Grain yield is most affected when rust arrives soon after heading, but losses are small if infection occurs after grain filling has started. Wheat streak-mosaic virus is transferred to winter wheat by a mite. Since the mite lives only on green vegetation, avoid planting winter wheat next to spring wheat fields that have not fully matured.

 

Harvesting Winter Wheat

Article - What happens if my Winter Wheat did not Emerge?

Winter wheat has little or no seed dormancy, and care must be taken to prevent sprouting once it reaches maturity. Straight combining can reduce the risk of grain sprouting.

Swathing

Wheat can be swathed when the kernels have 35 per cent moisture or less without loss of yield, bushel weight or quality. Kernels with 35 per cent moisture are firm and cannot be crushed with thumb and forefinger.

Combining

Wheat kernels with a moisture content of 14 per cent can be safely combined without the need for drying. Kernels with a moisture content of 20 per cent can be combined and dried without loss of quality.

Moisture

Wheat is dry and safe for one year storage at 14.5 per cent.

Storage

Moulds and mites tend to be inactive when storage moisture is below 13 per cent. If storage temperatures are below 8° C, insects are inactive, and below 3°C moulds become inactive.

For more detailed information on winter wheat, see the Winter Wheat Production Manual, at the local Manitoba Agriculture, Food and Rural Initiatives office.

For further information, contact your GO representative.