Reading the Windrow: How to Evaluate Hay Before Baling
By the time hay sits in the windrow waiting for the baler, the crop has been cut, tedded, and raked. The quality decisions are mostly made. But there’s still one critical call left: is the windrow ready to bale right now, or does it need more time? Reading this moment correctly separates producers who consistently bale top-grade hay from those who consistently end up with mixed results. Windrow evaluation for baling — the practice of assessing crop condition before pulling the PTO lever — is the last quality control step, and it deserves more respect than most operators give it.
This guide walks through the six-step evaluation sequence experienced producers use before baling — what to look for, what to measure, and what each observation tells you.
Step 1: Check Moisture — The Gatekeeper Variable
Step 01
Moisture determines everything. If moisture isn’t right, no other variable matters — the bale will either mold (too wet) or shatter leaves catastrophically (too dry). Target: 16–18% for small square bales, 14–16% for large round bales, 12–14% for large square bales.
How to check: A probe moisture tester inserted into the windrow at 10–15 spots gives an average reading. Spot-check in sunny and shaded areas — moisture varies across windrows by 3–5 percentage points. A windrow moisture test taken only at the edge of the windrow will read low; take samples from the center where the hay is denser and moisture tends to be higher.
If readings are 18–20%: hold for 1–2 hours and retest. If 20–25%: hold for 4–6 hours or consider tedding if drying is slow. If above 25%: bale only if conditioning with preservative is planned, otherwise wait a full day.
Step 2: Check the Stem-Test
Step 02
The stem-twist test is the old-school moisture check that still works. Grab a small handful of hay, twist the stems. Properly-dried hay crackles but doesn’t crumble; wet hay bends without breaking; over-dry hay shatters into fragments.
The twist test works because stem water content drops last during drying — leaves dry first, stems dry slower. A properly-dried windrow has dry leaves (indicated by rustling sound when handled) but slightly pliable stems (indicated by the stem-twist crackle rather than hard snap). When both leaves and stems are completely brittle, the crop is over-dry and leaf loss during baling will be excessive.
Step 3: Check Windrow Shape and Uniformity
Step 03
Walk the length of 2–3 windrows and visually assess uniformity. Ideal windrow: consistent width end-to-end, consistent height end-to-end, no bunches, no thin spots.
Why windrow shape baling matters: the baler is a constant-volume machine. A windrow that alternates thick and thin forces the baler to alternate between overfeeding (chamber jams) and underfeeding (soft bales). The result is poor bale consistency even with a properly-operated machine.
What to do if windrows aren’t uniform: the rake needs re-setting. Check rake pitch, ground pressure, and tine condition. For many operations, a simple mid-season adjustment fixes windrow quality problems that have been accepted as normal for years.
Step 4: Check Windrow Width vs Pickup Width
Step 04
Proper windrow size means windrow width 10–15% narrower than the baler pickup width. Wider windrows lose hay at edges; narrower windrows waste pickup capacity.
Quick check: measure windrow width with a tape or by pacing. For a 1.65 m pickup, target windrow width 1.35–1.45 m. Adjust on subsequent cuts if windrow is too wide (reduce rake offset or swath the crop with narrower setting) or too narrow (increase rake coverage or use double-raking).
Getting this right depends on rake selection as much as adjustment. Some crops mat and form narrow windrows despite aggressive raking; others spread and form wide windrows despite gentle handling. Our hay rake series covers wheel rakes, rotary rakes, and belt rakes — each designed for different crop conditions and target windrow geometries.
Step 5: Check Windrow Density
Step 05
Density is how much hay per linear meter of windrow. Feed the baler too light and bales come out soft-core; too heavy and the baler chokes. Target: match the baler’s designed intake rate.
Rule of thumb for 4×5 round balers: windrow should produce a tight, fully-formed bale in 90–120 seconds of baler operation at 8–12 km/h forward speed. Faster than that means too much hay density; slower means not enough. Adjust either ground speed (easy) or windrow density via raking patterns (harder, requires re-raking).
Step 6: Final Walk-Through — Foreign Objects and Problem Spots
Step 06
Before starting the baler, walk 100–200 meters of windrow looking for rocks, tree branches, baler twine from previous year, animal carcasses, or other foreign objects. These can destroy the baler chamber or contaminate the bale.
Foreign objects to watch for:
- Rocks and stones picked up by the rake from field margins — can damage pickup tines, jam feed chambers, or enter bales
- Baler twine fragments from previous year’s bales — wraps around rotating components and damages bearings
- Tree branches or bark from field edge — damage pickup tines and chamber belts
- Wildlife carcasses (raccoons, skunks, rabbits struck during mowing) — contamination hazard for livestock feed
- Weed patches (poisonous weeds like nightshade, ergot-infected grass) — contamination risk, especially for dairy and equine markets

The Quick Go / No-Go Checklist
For operators who want a fast decision framework, this checklist summarizes the 6 steps above:
- ✅ Moisture tested at 5+ locations, averaging in target range (16–18% for small squares)
- ✅ Stem-twist test confirms properly-cured hay (crackle, not crumble or bend)
- ✅ Windrows uniform in width and height along the length
- ✅ Windrow width 10–15% narrower than pickup width
- ✅ Windrow density produces bales in appropriate baler cycle time
- ✅ Walk-through completed, no foreign objects visible
All six green-lights: go. One or more red flags: hold, adjust, or retest. The 15 minutes spent on windrow evaluation for baling saves hours of problems downstream.
When Windrow Conditions Drift During Baling
A field baled from one side to the other over several hours will have different conditions at the end than at the start. Moisture drops during sunny afternoons; humidity spikes after dew-fall or scattered rain. The initial windrow evaluation isn’t the final word — re-check at intervals:
- Every 60–90 minutes on days with changing weather
- When transitioning between field sections with different exposure (sunny to shady, etc.)
- Immediately when moisture alarm sounds on balers equipped with in-chamber moisture sensors
- When bale weight changes noticeably — weight is an indirect moisture indicator
The Judgment Call
Windrow reading is part measurement, part experience. Seasoned operators develop an intuition for crop condition that transcends instruments — the way the hay smells, how it sounds when handled, how the windrow looks in afternoon light. New operators should rely heavily on moisture testers and measuring tapes; experienced operators use instruments to confirm what their senses already tell them.
Either way, the habit of deliberate windrow evaluation before every baling session separates professional-quality operations from ones that accept variable results. It takes 15 minutes; it saves hours of downstream problems; and it’s the single most leveraged quality-control practice in a hay production workflow. For tools that support this evaluation — moisture testers, probe thermometers, and related accessories — see our other product series.
Training New Operators on Windrow Evaluation
One of the biggest benefits of a structured windrow evaluation for baling checklist is how easily it transfers knowledge to new operators. Experienced operators often rely on intuition developed over decades; new hires have no such intuition. A written, repeatable evaluation sequence gives new operators a framework that delivers consistent results from day one while they develop their own feel over seasons.
Training approach that works:
- Walk the fields together during the first baling sessions. Experienced operator narrates what they see; new operator observes and asks questions.
- Use the 6-step checklist formally — print it, laminate it, keep it in the tractor cab. New operators work through it explicitly before each baling session.
- Calibrate with moisture testers — have the new operator make a prediction, then test. Feedback loop develops intuition faster than abstract explanation.
- Review bale quality together — open bales from good and bad windrows, show how the evaluation indicators predicted outcomes.
- After season one, the structured checklist gradually becomes internalized. New operators can drop the written list and rely on their own developing intuition.
Windrow Evaluation on Different Crops
The general framework applies across crops, but specifics vary. Alfalfa evaluation emphasizes leaf retention and moisture; grass hay evaluation emphasizes curing uniformity and stem-dry state; mixed hay requires judgment on which crop drives the decision (usually alfalfa if it’s >25% of the mix). Cereal forages (oats, wheat, rye) have their own quirks — they tend to look drier on the surface than they actually are in the stem, making moisture testing especially important.
Recommended Companion Product
Precision Hay Rake Tines — Heat-treated, spring-steel rake tines that form uniform windrows and preserve leaf content. Fits major wheel and rotary rake brands; sold in 10-tine, 20-tine, and full-set quantities.
Start with the Right Windrow — Every Time
The right rake, the right tines, and the right evaluation tools set the foundation for top-grade baling.