Quick answer: For dry round bales you'll net-wrap and stack, aim for roughly 16–18% moisture or less — many producers prefer 12–16%. Above about 18% you're gambling; at 20%+ you'll smell it heating within a day or two, and those bales need to be kept separate and spread out for 30–45 days. Net wrap doesn't preserve wet hay — it only holds shape. If the hay is genuinely too tough to bale dry (stem moisture in the 20s or higher), the real fix is individual plastic wrapping (baleage) or waiting it out, not backing off bale pressure.
Net wrap holds a bale's shape — it does nothing to preserve wet hay. A net-wrapped round bale is a dry-hay package, so the moisture rules are the same as any dry round bale: bale it too wet and it molds, heats, and in the worst case catches fire. The producers in the hay forums are strikingly consistent on the numbers, and on the one fact that matters most: net wrap is not a substitute for getting the hay dry.
The target: 16–18% and under for dry net-wrapped bales
Ask what moisture to bale dry alfalfa at and the answers cluster tightly in the mid-teens. One producer getting buyer requests laid out the spread:
"What are your guys's Moisture on Alflafa you're are gonna sell? Have some guys wanting 18% and some wanting 23%"
— hooligans · AgTalk thread 859044
The replies pulled hard toward the dry end:
"In a pinch 20 or less. Ideally 14-16"
— novaman, Oklahoma · AgTalk thread 859044
"I would be concerned with mold at those moisture levels. I like to see 16 or less."
— dt4020, ND · AgTalk thread 859044
"18% would be about as wet that would store good here."
— cattledriver, SW MT · AgTalk thread 859044
Climate matters — a humid northeast summer is less forgiving than dry Montana air — but the headline number holds: 16% is the comfortable target, 18% is the upper edge, and over 20% is asking for trouble.
What happens when you push past 18%
The risk above ~18% isn't just mold — it's heat. A wet bale ferments and warms, and a stack of warm bales is how barn fires start. One Nebraska producer gave the clearest field rule for the danger zone:
"18% is a hit or miss type deal, 20+ you'll be smelling it in a day or two. Will want to keep them bales over 20 separate and spread out for a good 30-45 days. I prefer to bale 12-15%."
— Jim, Ne Nebraska · AgTalk thread 941259
That's the safety play if you get caught a little wet: don't stack borderline bales tight. Keep anything over 20% separated and spread out so it can shed heat for a month or more, and check them. A tight stack of warm, wet bales is the worst-case combination.
Trust the test, not just the cab readout
Baler-mounted moisture sensors are useful, but seasoned operators treat them as a relative gauge for finding wet spots, not the final word. They cross-check with bale weight and a hand test:
"If that moisture reading is correct it is right on the edge of being to tuff in my opinion. My Vermeer has moisture sensor and a scale. I will go off the scale before i trust moisture sensor. Weight says alot."
— Alberta Cowman, EC IA · AgTalk thread 941259
"I find my baler mounted sensor is a good "relative" gauge for finding tough spots or when the dew comes on. It's generally reading from the outside of the swath. I still rely on a probe or twist test to make the "go- no go" call. If you can put the tough stuff from the headlands on the outside 6" of the bale you would be safe. Easier said than done though."
— Direct Injected · AgTalk thread 941259
The other variable is where the moisture is. The producer who started that thread was seeing big swings near the woods, and the first question back was about the kind of moisture:
"Stem moisture or dew moisture? If its stem, id be wrapping. Even dew moisture that's getting up there with no juice applied..."
— Wilbur71, SE SD · AgTalk thread 941259
Dew that will dry off behaves differently than stem moisture that's locked in the plant. If it's stem moisture into the 20s, dry net-wrapping is the wrong tool.
The hard truth: net wrap (and low pressure) won't save tough hay
The most useful cautionary tale in these threads is the producer who tried to bale tough alfalfa dry and lost it — then asked whether backing off bale pressure would let the bales "breathe":
"Have some a little tough with rain on the way. I had the same thing last year and baled it. It didn't keep, got all moldy. Running a NH 648 with net. I thought I'd back off the bale pressure hopefully they won't pack as tight and breathe out. Will this work or is it just a waste of time"
— olderthandirt, Finger Lakes · AgTalk thread 1066645
The answer from the forum was blunt and unanimous:
"It won't work. Can you hire someone to wrap it individually or tube it? Otherwise wait it out."
— DHH, NW IA · AgTalk thread 1066645
Loose-baling wet hay doesn't dry it; it just makes a loose moldy bale. The real options for hay that's too wet to bale dry are to wrap it in plastic as baleage or wait for it to cure.
If it's genuinely too wet: wrap it, don't net it
This is where the moisture rules split. Net wrap is for dry hay; plastic wrapping (baleage) is the tool for wet hay, because sealing it in plastic ferments and preserves it instead of letting it mold. As one producer who wraps put it:
"The beauty of bale wrapping is you don't need to worry about the moisture as long as the baler will bale it. We always wrap right after baling and I can't remember ever waiting til the next day. The wetter it is the quicker you need to get it wrapped."
— redrider806, Southern Indiana · AgTalk thread 1114037
So the decision tree is simple: if you can get the hay to roughly 16–18% or drier, net-wrap it as dry hay. If it's stuck in the 20s–50s and rain is coming, plastic-wrap it as baleage instead. Don't try to net-wrap your way out of wet hay.
Moisture guide for net-wrapped dry bales
| Moisture (round bale) | What farmers report | Action |
|---|---|---|
| 12–16% | Preferred range; stores and sells well | Net-wrap and stack normally |
| 16–18% | Upper edge of "safe" in most climates | OK to net-wrap; monitor the stack |
| 18–20% | "Hit or miss"; risk of mold and heat | Keep loose, watch closely, don't stack tight |
| 20%+ | Will heat and smell within days | Keep separate and spread 30–45 days — or wrap as baleage |
| Stem moisture 25%+ | Too wet for dry hay | Plastic-wrap (baleage) or wait it out |
These are producer-reported figures, not lab specifications. Humid climates are less forgiving; check your own bales with a probe and watch the stack for heat.
Where XES fits
Net wrap's job is to hold a properly-dried bale tight and round through storage and transport — and it does that job well only on hay that's actually dry. Our wrap is DLG-tested (Report #7439) and UV-rated for 12 months (tested to ISO 4892-2), so dry bales hold their shape and shed weather outside. Compare widths and lengths on the net wrap product page, and once your hay is in the right moisture range, dial in your wrap count per bale and plan your outdoor bale storage.
The bottom line
For net-wrapped dry bales, target 16% or less, treat 18% as the upper limit, and treat 20%+ as a heat-and-mold hazard that must be kept separate and watched. Cross-check the cab sensor against bale weight and a twist test, and pay attention to whether you're reading dew or stem moisture. And remember the rule the forums repeat every season: net wrap holds shape, it doesn't preserve wet hay — if it's too tough to bale dry, wrap it in plastic or wait.
Frequently asked questions
What moisture should I bale round bales at for net wrap?
Aim for about 16% or less, with many producers preferring 12–16%. Up to 18% is the upper edge of safe in most climates. Net wrap only holds the bale's shape — it doesn't preserve the hay — so the moisture target is the same as for any dry round bale you'll stack and store.
Is 20% moisture too wet for net-wrapped hay?
For dry storage, yes — it's in the danger zone. Producers report bales over 20% start to smell and heat within a day or two. If you get caught baling that wet, keep those bales separated and spread out for 30–45 days so they can shed heat, and watch them closely. Better to dry to under 18% or wrap as baleage.
Can I bale wet hay looser so it breathes and doesn't mold?
No. Producers who tried backing off bale pressure to "breathe out" tough hay still ended up with moldy bales — the consensus answer is that it won't work. Loose-baling wet hay just makes a loose moldy bale. The real options for too-wet hay are individual plastic wrapping (baleage) or waiting for it to cure.
Should I trust my baler's moisture sensor?
Use it as a relative gauge to find tough spots and dew, not as the final word. Experienced operators cross-check the cab reading against bale weight (a scale) and a hand probe or twist test to make the go/no-go call. Sensors typically read the outside of the swath, so they can miss stem moisture locked inside the plant.
When should I plastic-wrap instead of net-wrap?
When the hay is too wet to bale dry — roughly stem moisture in the 20s or higher with no chance to dry. Net wrap is for dry hay; plastic wrapping (baleage) seals and ferments wet forage so it preserves instead of molding. If you can get the hay to 16–18% or drier, net-wrap it; if it's stuck wet and rain is coming, wrap it in plastic.
This guide is maintained by the XES Netting team — a bale net-wrap manufacturer. Every farmer quote in this post is verbatim with a thread link, so you can go read the originals. Moisture figures here are producer-reported starting points, not lab specifications — check your own hay and watch your stack for heat, because wet bales can ignite.
Featured photo: Round baler 3061 by Flominator, licensed under CC BY-SA 3.0, via Wikimedia Commons.
