Principles of Producing High-Quality Hay
Producing high-quality forage reduces feed costs by maximizing protein and energy content. This is achieved through proper species and variety selection, harvesting and storage practices. Producing premium hay requires precise timing and careful management.
 
Key Principles:
·        Species and Variety Selection: match your livestock needs and growing conditions.
·        Fertility Management: Forages require proper nutrition to maintain yield and quality
  • Timing: Cut hay at the ideal growth stage for maximum nutrient value.
    • Cutting crops like alfalfa just before flowering and harvesting quickly under good weather conditions can yield protein levels above 25% and energy levels above 65%.
    • Delayed cutting decreases crude protein, dry matter digestibility, and intake, reducing overall forage quality.
For more information please see the Producing High Quality Dry Hay: Best Practices
 
Choosing the Right Species
  • Dairy Operations: Pure alfalfa provides high protein and energy.
  • Beef Operations: Grass or grass-legume mixes often meet nutritional needs without excess richness.
  • Dual Purpose: Some species work well for both hay and pasture systems.
Variety Selection
Once species are chosen:
  • Consider winter hardiness, disease resistance, soil type, and management style.
  • For Manitoba, winter survival and disease resistance are critical for stand longevity.
Resource: Seed Manitoba (www.seedmb.ca) offers tables on:
 
Fertility Management
  • Hay stands remove most nutrients during harvest; unlike pastures, nutrients are not returned via manure.
  • Soil Testing: Essential before seeding and throughout the stand’s life.
  • Nutrient Removal per Tonne of Hay:
    • Grass hay: ~16 kg N, 5 kg P, 24 kg K, 2 kg S
    • Alfalfa: ~22 kg N, 4 kg P, 20 kg K
      (Values are approximate; hay analysis provides more accuracy.)
Key Points:
  • Pure alfalfa: No added nitrogen; requires phosphorus and potassium for root health and winter survival.
  • Grass stands: Require nitrogen for productivity.
  • Mixed stands: Need balanced fertility for both species.
Reference: Manitoba Soil Fertility Guide for detailed recommendations.
 
Cutting Times: Stage of Growth
Determining the best time to cut hay depends on weather conditions, species or species mix, intended use, and stand maturity. Cutting at the right stage ensures optimal Relative Feed Value (RFV), which measures forage digestibility and potential dry matter intake.
The maturity of forage at cutting is the most critical factor affecting quality:
  • Young, Vegetative Forage: Higher in protein and energy.
  • Older, Flowering Forage: Lower nutritional value.
  • First-Cut Alfalfa: Quality declines rapidly; for premium forage (e.g., dairy or cash hay), cut early—around June 10–15.
 
Why It Matters
Once cut, hay begins losing Relative Feed Value (RFV) or Relative Forage Quality (RFQ). Understanding how management practices affect drying and handling is critical to minimize losses.
Relative Feed Value (RFV) - an indicator of forage quality, based on a combination of acid detergent fibre (ADF) and neutral detergent fibre (NDF). For high-quality hay to be fed to dairy cows or sold in the cash hay market, an RFV of 150 is considered ideal.
Relative Forage Quality (RFQ) RFQ is an estimate of how much available energy a non-lactating animal will obtain daily from a particular forage if it is all that is fed. RFQ includes the digestible fibre and is a much better estimate for all grasses and grass-legume mixes except corn silage.   
 
Cutting Times for High-Quality Hay
Key Considerations
  • Match RFV to Animal Needs:
    • Dairy cows and calves require higher RFV (140–150).
    • Dry cows and heifers can utilize lower RFV hay (100–120).
    • Cutting earlier than necessary provides insurance against poor drying conditions.
  • Species Differences:
    • Grass and grass-mix stands reach RFV 150 faster than pure alfalfa.
    • Alfalfa-grass mixes should be cut about one week earlier than pure alfalfa for similar RFV.
RFV Decline After Cutting
  • Hay loses ~5 RFV points per day during drying; losses increase with prolonged drying or rain.
  • To achieve a final RFV of 150, cut at ~180 RFV.
Growing Degree Days (GDD) and RFV
  • 300–350 GDD: RFV ~180 (ideal for first cut).
  • 350–400 GDD: RFV ~160.
  • 450–500 GDD: RFV ~140.
    Calendar dates vary by up to three weeks annually—use GDD for accuracy.
Forage Quality Needs of Cattle - (Relative Feed Value)
  • Dry cow/heifer (18–24 months): RFV 100–110
  • Beef cow/calf, heifer (12–18 months): RFV 120–130
  • Dairy last 200 days, heifer (3–12 months), stocker cattle: RFV 130–140
  • Dairy first trimester, dairy calf: RFV 140–150
 
Cutting Guidelines by Week
Data within Manitoba shows RFV declines rapidly after mid-May, emphasizing the need for timely cutting. A Predictive Equation for Alfalfa Quality Stick (PEAQ) can be used as a measurement tool. 
(Predictive Equation for Alfalfa Quality – PEAQ)
Week
Alfalfa
Alfalfa/Brome
Alfalfa/Timothy
1
275
217
230
2
204
162
178
3
164
138
178
4
130
113
121
5
116
105
101
 
 
Best Practices
  • Use GDD and RFV monitoring, not calendar dates, for cutting decisions.
  • Cut earlier for grass mixes and when aiming for high-quality dairy hay.
  • Avoid delays—quality drops quickly after optimal stage.
Why Crop Stage Matters
  • The same maturity stage at different times of the year can result in different RFV.
  • RFV declines rapidly after cutting, so precise timing ensures optimal feed quality.
 
Recommended Monitoring Methods
  • First Cut:
    • Use the Predictive Equation for Alfalfa Quality (PEAQ) measuring stick, available from Manitoba Agriculture, for the most accurate RFV estimate.
  • Second and Subsequent Cuts:
    • Rely on crop staging and accumulated GDD for timing decisions.
 
Time of Day and Forage Quality
Impact on Nutritional Composition
The time of cutting influences hay quality because plant sugars fluctuate throughout the day:
  • Morning: Lowest sugar content due to overnight respiration.
  • Evening: Highest sugar and energy levels after a full day of photosynthesis.
Considerations for Hay Producers:
While late-day cutting increases sugar content, it can lead to losses if hay does not dry quickly:
  • Cut hay continues to respire overnight, reducing dry matter.
  • Warm nights accelerate losses:
    • At 20°C, hay at 70% moisture can lose ~2% dry matter in 12 hours.
    • At 30°C, losses can reach ~3% overnight.
Fast drying under good weather conditions is essential to preserve quality.