Alfalfa

Alfalfa is a top choice for forage in dryland farming systems due to its deep-rooting system, which allows it to access moisture far below the surface, making it highly drought-resistant. It provides excellent forage for livestock, improves soil fertility, and increases yields when used in crop rotations. Below is a comprehensive overview of alfalfa cultivation in dryland systems, particularly focusing on Alberta’s Special Areas.

1. Seed Selection

Choosing the right alfalfa variety is critical for optimizing yields, drought resistance, and persistence in harsh environments. Several factors influence variety selection, including disease resistance, winter hardiness, and suitability for grazing versus hay production.

Best Varieties for Alberta Special Areas:

• AC Blue J
  • Excellent winter hardiness and good drought tolerance.
  • High forage yield with fine stems, making it ideal for hay production.
  • Moderate resistance to bacterial wilt and verticillium wilt.
• Spredor 4
  • Suited for grazing due to its spreading growth habit, which fills in bare spots over time.
  • Resistant to lodging and maintains a good stand under grazing pressure.
  • Strong resistance to crown and root diseases.

Additional Recommended Varieties:

• Beaver – Proven to perform well in dryland environments with high forage yield and persistence.
• Rugged – Great for rotational grazing and hay due to its rapid regrowth after cutting.
• Haygrazer – Suitable for areas prone to variable moisture levels.

Factors to Consider in Seed Selection:

• Winter Hardiness: Alfalfa must survive harsh winter conditions to ensure long-term productivity. Look for varieties rated at Winter hardiness 2 or better.
• Fall Dormancy: Fall dormancy ratings between 2 and 4 provide the best balance between yield and winter survival.
• Disease Resistance: Prioritize resistance to bacterial wilt, fusarium wilt, and verticillium wilt, which are common threats in semi-arid regions.

2. Planting Guidelines

Site Preparation:

• Weed Control: Control perennial weeds before planting. Chemical or mechanical control methods can prevent weed competition during establishment.
• Soil Testing: Conduct a soil test to determine nutrient requirements and pH balance. Alfalfa prefers a pH of 6.5–7.5 for optimal growth.
• Seedbed Preparation: Create a firm, fine seedbed to ensure good seed-to-soil contact. Rolling after planting can improve seedling establishment.

Seeding Time:

• Spring Seeding: Best between late April and early May when soil temperatures exceed 10°C (50°F).
• Late Summer Seeding: For fall establishment, plant between mid-August and early September, giving seedlings enough time to establish before frost.

Seeding Rate:

• Pure Stand: 8–12 lbs/acre broadcast or 6–8 lbs/acre drilled.
• Mixture with Grass: 5–8 lbs/acre, depending on grass species and intended use.

Seeding Depth:

• Optimal depth is ¼–½ inch. Avoid planting too deep, as alfalfa has small seeds that require shallow placement for successful germination.

Inoculation:

• Use a high-quality Rhizobium inoculant specific to alfalfa to ensure nitrogen fixation and enhance plant vigor.

3. Fertilization and Soil Management

Nutrient Requirements:

• Phosphorus (P): Essential for root development and stand persistence. Apply 20–40 lbs/acre annually based on soil tests.
• Potassium (K): Critical for stress resistance and winter survival. Aim for 120–150 lbs/acre to maintain optimal potassium levels.
• Sulfur (S): Essential for protein synthesis. Apply 10–20 lbs/acre annually, especially on sandy soils.

Lime Application:

• Alfalfa prefers neutral to slightly alkaline soils. Apply lime to maintain a soil pH between 6.5 and 7.5.

Micronutrients:

• Boron: Essential for flowering and seed production. Apply 1–3 lbs/acre if soil tests indicate deficiency.

Fertilizer Timing:

• Pre-Planting Application: Incorporate phosphorus, potassium, and sulfur into the soil before planting.
• Top-Dressing: Apply additional potassium and sulfur in spring or after first cut to support vigorous regrowth.

4. Growing and Management Practices

Weed and Pest Control:

• Pre-Plant Control: Eliminate perennial weeds like Canada thistle and quackgrass using herbicides or tillage.
• Post-Emergence Control: Use selective herbicides such as Metribuzin or Imazethapyr to manage broadleaf weeds during establishment.
• Insect Control:
  • Alfalfa Weevil: Monitor and control with appropriate insecticides when threshold levels are met.
  • Aphids: Introduce biological controls if populations exceed 40 per stem.

Grazing and Cutting Management:

• Grazing: Rotate livestock to prevent overgrazing and allow for adequate regrowth. Maintain a minimum stubble height of 3 inches for regrowth.
• Hay Cutting:
  • First Cut: When 10% of blooms are open, maximizing forage quality and yield.
  • Subsequent Cuts: Allow 28–35 days between cuts for regrowth.
• Rest Period: Ensure alfalfa has at least 6 weeks of growth before the first killing frost to prepare for winter.

5. Harvesting and Storage

Hay Production:

• Timing: Cut at the early to mid-bloom stage to balance yield and quality.
• Moisture Content: Aim for 15–18% moisture to avoid spoilage during storage.
• Baling: Round bales should be wrapped or stored under cover to prevent spoilage, while square bales should be stacked with adequate ventilation.

Silage Production:

• Moisture Content: Harvest at 60–65% moisture for ensiling.
• Packing: Ensure adequate packing to eliminate air pockets and promote fermentation.
• Storage: Cover silage with plastic to maintain quality and prevent spoilage.

6. Resources and Support for Alfalfa Farmers

Government and Industry Support:

• Alberta Agriculture and Irrigation (AFSC): Provides financial programs, crop insurance, and forage production resources.
• Prairie Agricultural Machinery Institute (PAMI): Offers research on forage harvesting technologies and storage methods.
• Canadian Forage and Grassland Association (CFGA): Offers research and support for forage management in semi-arid regions.

Extension Services and Expertise:

• Agricultural Fieldmen in Special Areas: Provide guidance on pest management, soil health, and seeding recommendations.
• Alberta Ag-Info Centre: Offers information on forage variety performance, pest control, and agronomic practices.

Financial Assistance Programs:

• On-Farm Climate Action Fund (OFCAF): Supports producers adopting nitrogen management and cover cropping practices.
• Canadian Agricultural Partnership (CAP): Provides funding for projects that enhance forage productivity and soil health.

7. Conclusion

Alfalfa remains an excellent choice for dryland farming in Alberta’s Special Areas due to its drought resilience, high forage quality, and nitrogen-fixing benefits. By selecting suitable varieties, implementing proper planting and management practices, and leveraging available resources, farmers can optimize yields while maintaining sustainable production.