Third-cut in Ontario tends to sneak up on you. The field looks lighter than second-cut, the bales feel softer, and everything about the harvest suggests easier going. Then you open the mixer and watch six-inch stems ride the auger like they own it. Wet, pliable, and long, third-cut stem length is a different problem than the dry, brittle material you were running in June, and your twin-auger VT needs to be set up differently to handle it.
This matters right now because third-cut and corn silage prep overlap in most of Ontario. You are dealing with one forage type this week and a completely different one the week after. The operators who handle that transition well tend to think through their setup before the first batch goes in, not after three poor mixes tell them something is wrong.
How Third-Cut Stem Length Changes Your Fill Order and Mix Time
Fresh third-cut haylage typically comes in wetter than second-cut, often well above 60% moisture. That changes how the material behaves in the tub. Wet stems mat together, resist separation, and when you load too much at once, they form a dense plug that sits on top of the auger rather than feeding into it. The auger lifts material, but lifting a sodden mat is not the same as tumbling loose, dry hay.
The standard advice on fill order still applies: heaviest, densest material first so the auger has something to bite against when lighter ingredients come in. With wet third-cut, that means silage or haylage goes in first, concentrates and minerals next, and any long-stem hay or straw last. What changes is the timing. Wet stems need longer in the tub before they yield a clean cut. Where second-cut hay might be well incorporated after eight minutes of mixing, third-cut in this condition can need two or three minutes more, depending on stem diameter and how tangled the bale was packed.
Watch your load weight carefully. Load cells on a properly rated machine give you real data, and overloading a wet batch compounds every mixing problem downstream. Overloaded tubs lose the material transfer zone at the top of the shell, which is where loose material needs to flow freely between augers. Once that zone packs out, mixing uniformity drops fast.
If you are running a larger twin-auger machine and want to understand how bowl volume interacts with ration type, the sizing logic for mid-sized operations covers the relationship between tub geometry and mixing behaviour in useful detail.
Knife Engagement and Kicker Behaviour With Long Stems
Long wet stems have a way of folding around a knife rather than presenting cleanly to it. That is actually something auger design accounts for. Hay knife reliefs, the cutaways machined into the auger flight, are specifically there to let longer stem material fold over the knife edge so it cuts the way you would fold a rope to slice it cleanly. Without that geometry, long stems skate past the knife face and accumulate on the auger.
Knife position matters more with third-cut than with most other forages. For round bales or long-stemmed material like third-cut haylage, positioning the smaller knife on top tends to produce better early engagement. The larger knife on top is better suited to pre-chopped roughage or high-density silage with little long-stem material. Get the order wrong in August and you will spend extra mixing time compensating for poor initial cut.
Check knife wear before you run a third-cut batch. A dull edge on wet stem material is worse than on dry hay because wet stems deform rather than cut. If your edges are borderline, this is the forage that will expose them.
The kicker is the other variable that operators tend to underestimate. A worn or undersized kicker lets material pack against the tub wall instead of lifting and rolling back into the auger column. With wet, matting stems, that dead zone at the wall gets worse quickly. The kicker scrapes the wall, lifts material, and maintains the rolling circulation that prevents packing. When it is working properly you get shorter mix times and lower torque demand. When it is worn, those long third-cut stems find every dead spot in the tub and stay there. Replacing or upsizing a kicker plate is one of the lower-cost interventions that has a measurable effect on mix uniformity with difficult forages.
A more aggressive kicker profile helps with wet, dense material, but it also draws more torque. Know your tractor’s PTO rating before you upsize. The goal is better material movement, not a stalled drive line.
For a more complete breakdown of how kicker geometry affects mix quality across different ration types, this piece on kicker behaviour and morning batches is worth the read.
Auger Wall Pressure Zones and Wet Forage
A twin-auger machine creates three functional zones inside the tub: a low-pressure zone at the top for material transfer, a medium-pressure zone in the middle where most mixing happens, and a high-pressure zone near the bottom where knives work hardest. Wet third-cut material is heavy enough to shift a lot of your batch weight into the bottom zone before the auger gets a chance to lift and circulate it. That compresses mix time into one zone and reduces the uniformity you get from working material through all three.
Running slightly smaller batch sizes with wet third-cut helps maintain circulation across all three zones. It costs you a batch or two per day but tends to produce a noticeably more consistent particle distribution. The cows will sort less, and the next day’s production numbers will usually reflect it.
Auger-to-wall spacing is also worth checking periodically. Proper clearance between the auger and tub wall is one of the geometry factors that affects whether wet, clumping material gets worked or just dragged. If your machine has seen a full season without an inspection, check it before the third-cut batches start.
Pre-Silage Check Sequence Before Corn Silage Week
The shift from third-cut haylage to corn silage is one of the bigger ration transitions of the year. Corn silage is denser, wetter at the face, and has a completely different particle structure. A machine that has been running long-stem haylage all week needs to be verified before you change rations, not assumed to be fine.
Work through this sequence before your first corn silage batch:
- Pull and inspect every knife. Wet haylage dulls edges without the obvious visual wear you get from dry hay. Check the cutting face, not just the bolt condition. If you are running a modular knife system with replaceable outer edges, this is a fast job. If not, budget the time properly.
- Check kicker condition and bolt torque. Wet material batches put consistent side-load on the kicker mounting. A loose kicker on a corn silage batch is worse than a worn one because it moves unpredictably.
- Inspect the tub walls for material buildup, particularly at the base of the shell and around the discharge door frame. Third-cut haylage leaves residue that ferments quickly and can contaminate a fresh corn silage batch.
- Zero and verify your scale. Run the tare cycle, put a known weight on the platform if you have one, and confirm the load cell reading matches. Corn silage is dense enough that a scale error of even a few percent throws your dry matter off meaningfully.
- Check discharge door seals and door travel. Corn silage flows differently than haylage and a door that was closing well on fibrous material may bridge or leave residue on stickier silage.
LEO Agriculture’s VT Series runs from 6 to 21 cubic metres, and the machines share the same knife relief geometry and kicker mounting system across the range. If you are switching ration types mid-season, the inspection steps above apply regardless of which size you are running.
The underlying point is straightforward: third-cut stem length is a specific technical challenge, not just a forage type. The moisture content changes how material loads, how knives engage, and how the tub circulates. Set the machine up for it deliberately, run your pre-silage check before you switch rations, and the same VT that handles wet haylage this week will handle corn silage cleanly the week after.
