How to Read a Forage Analysis (Without a PhD)
Every reputable hay seller should hand you a forage analysis with the load. We do. But most people glance at the page, see a wall of acronyms, and trust that whoever ran the test knew what they were doing. Here's how to actually read the page.
The five numbers that matter
For perennial peanut hay (and most forage), focus on these five:
1. CP — Crude Protein
This is the headline number. It tells you what percentage of the hay's dry matter is protein.
| Forage | Typical CP |
|---|---|
| Coastal bermuda | 6–10% |
| Bahia | 7–11% |
| Perennial peanut | 14–18% |
| Alfalfa | 17–22% |
For most horses, 14%+ is excellent. For hard-working horses, growing animals, or lactating goats/ewes, aim for 16%+.
2. TDN — Total Digestible Nutrients
TDN is the percentage of the hay your animal can actually extract energy from. Bulk fiber that passes through is not TDN.
- Below 50%: low-quality, "filler" hay
- 50–58%: acceptable for easy keepers
- 58–65%: excellent feed value (where good perennial peanut lives)
- 65%+: rare in dry hay, more common in pasture
3. ADF — Acid Detergent Fiber
ADF measures the least-digestible part of the plant (cellulose and lignin). Lower is better.
- Below 30%: very soft, palatable hay
- 30–35%: ideal range for perennial peanut
- 35–40%: still good
- Above 40%: hay is over-mature, stems are coarse
4. NDF — Neutral Detergent Fiber
NDF measures total fiber. It correlates with how much hay your animal will actually eat in a day. Lower NDF = higher intake.
- Below 45%: animals eat a lot, gain weight easily
- 45–55%: balanced
- 55–65%: animals fill up before they get enough nutrition
5. RFV — Relative Feed Value
RFV is a single composite score that combines ADF and NDF. It's the "credit score" of hay.
- Below 85: low quality
- 85–100: average
- 100–125: very good
- 125–150: excellent
- 150+: rare, premium
Good perennial peanut hay routinely tests 110–140 RFV. If you see numbers in that range, you're looking at quality hay.
Other numbers you'll see (less critical)
- Calcium (Ca): matters for lactating animals. Perennial peanut: 1.0–1.5%.
- Phosphorus (P): balance with Ca. 4:1 to 6:1 Ca:P ratio is healthy.
- Magnesium, Potassium: rarely deficient in legume hay.
- NSC / WSC / ESC: sugar and starch. Important for laminitis-prone or insulin-resistant horses. Perennial peanut is typically low NSC.
- DE (digestible energy): energy per pound. Higher = more calories.
A real example
Here's a recent lab analysis from one of our cuts:
| Metric | Value |
|---|---|
| CP | 16.2% |
| TDN | 62% |
| ADF | 33% |
| NDF | 42% |
| RFV | 138 |
| Ca | 1.3% |
| P | 0.22% |
Translation: this hay is excellent quality. Horses will eat it well (low NDF), get good energy (high TDN), and pull serious protein from it (16.2% CP). RFV of 138 puts it in the top tier.
Red flags on a forage analysis
- CP below 12% for any legume hay — something went wrong in the cut or storage
- ADF above 40% — over-mature, coarse, animals will waste it
- RFV below 90 — this is filler hay
- Mold rating mentioned — never buy moldy hay, even if other numbers look good
- Sampling method not noted — proper samples are core-pulled from multiple bales
Always ask for the test
Any hay seller selling premium-priced hay should be able to produce a current forage analysis. We post ours publicly with every cut. If a seller can't show you the lab report, you're paying premium price for unverified hay.
See current cut's forage analysis → or text (850) 573-0470 or (850) 573-0471 to get the latest report.