Every June the same argument runs in ranch pickups from the Bitterroot to the Milk River: cut the alfalfa now while it’s leafy, or let it stand another ten days and put more in the stack. The scale says wait. The cow says don’t. Both are right, which is why the decision is worth more thought than most producers give it while they’re greasing the swather.
Here’s the short version. Alfalfa dumps most of its feed value into the leaves. As the plant matures toward bloom, it keeps adding stem to hold those flowers up, and stem is mostly fiber the cow can’t get much out of. So a field cut in late bud or first flower weighs less per acre than the same field cut two weeks later at full bloom, but every mouthful of it is worth more. You’re trading protein and energy for tonnage, and the exchange rate is not in your favor as often as people think.
What the extra week actually costs
Let the field go to full bloom and you’ll see the yield jump. That’s real. But look at what came with it. The stems got coarser, the leaf-to-stem ratio dropped, and the protein and digestible energy per pound fell right along with it. A cow can only eat so much in a day. If the hay is stemmier, she fills up before she gets what she needs, and either she loses condition or you make up the difference with something out of a sack.
The trap is that the loss doesn’t show up on cutting day. It shows up in February, when a cow chews through the leaf and leaves a windrow of gray stems in the feed bunk. You paid to grow those stems, paid to bale them, and paid to haul them. Then she wastes them. That refusal is the quality you cut out of the field back in June, showing up as waste hay six months later.
The other cost of waiting is regrowth. Alfalfa starts pushing new shoots from the crown before you ever cut the standing crop. Let the plant go too far into bloom and you’re mowing off that new growth, which sets back your second cutting and, over years, wears on the stand. Cutting closer to the bud stage keeps the plant on a schedule that favors more cuttings and a longer-lived field.
Reading the plant instead of the calendar
Forget the date on the fence post. The plant tells you where it is. Walk out and look at the buds. Late bud to about ten percent bloom is the window most people are shooting for on a hay crop meant to actually feed something through a Montana winter. Once you see purple across the field, you’re already into the tradeoff.
Weather complicates it, and this is where the calendar wins some arguments. A stretch of hot, dry days that lets you cut, cure, and bale without a shower is worth more than a few extra days of standing crop that gets rained on. Rain leaches soluble nutrients out of a cut windrow and bleaches it. A slightly stemmier crop baled dry and green beats a leafy crop that took two rains lying on the ground. If you’ve got a clear four or five days in the forecast and the field is at bud, that’s your signal, even if the yield would climb with more time.
A few things to weigh before you drop the header:
- What are you feeding it to? Bred cows in good flesh can get by on stemmier hay. Bred heifers, thin cows, or anything you’re pushing need the leaf.
- How’s the stand? An older, thinning field won’t gain much tonnage by waiting, so there’s little reason to sacrifice quality on it.
- What’s the sky doing? A guaranteed dry window at bud stage almost always beats gambling on bloom-stage tonnage through a rain.
If you sell hay instead of feeding it, the math shifts. Buyers who want cow hay may not pay a premium for dairy-quality leaf, and the extra tonnage puts money in your pocket. Know your market before you decide the cow is the only one at the table.
Test it before you guess
The only way to actually know what you put up is to pull a core sample and send it in. Eyeballing a stack tells you color and roughly how stemmy it is, but not the protein or energy number you’d budget a winter ration around. A test costs little against the price of feeding blind and finding out in a hard March that your hay was a grade thinner than you thought.
Cut a little early and you’ll bale fewer tons of better hay. Cut a little late and you’ll bale more tons of hay the cow argues with. Most winters, on most Montana ranches, the leaf is worth more than the extra weight. Set the swather accordingly.
