The first white frost in West Texas can make a pasture seem safe. Leaves hang down, the season looks over, and opening another field might seem like a simple way to cut winter hay costs.But that choice is not always safe.
Frost can harm plant cells in sorghum, sudangrass, johnsongrass, and sorghum-sudan hybrids, which can quickly release prussic acid. The field might also have high nitrate levels from drought, heavy nitrogen use, cloudy days, or uneven growth. Both issues can be deadly for cattle, but they act differently and need separate tests.
So, the answer to “How long should cattle wait after frost?” depends on the type of plant, the kind of freeze, the field’s history, and whether new growth shows up.
October weather rarely makes things easy. One low area might freeze while a sheltered terrace stays green. A light frost can burn the tops but not kill the plant, and warm afternoons can bring out new shoots. Check what is growing before letting cattle in.
Seeing a green wheat field in October can really test your patience. Native grass is fading, hay prices are rising, and that fresh wheat looks like the perfect feed just beyond the gate.
September often tempts you to squeeze in one more pasture rotation. With the calves gone, cows still need feed, and there’s still green under the seedheads. Keeping them in that paddock another week might save hay or put off using winter pasture.
If you have spent any time running cattle in West Texas, you know not to count on the rain.
September often makes wheat pasture seem like a quick way to earn money. Someone at the feed store mentions that calves should gain well this winter; a bit of rain moistens the ground, and soon everyone is eager to start planting.
September in West Texas can be misleading. Although the pasture still has brown grass, the cows are scattered about, and one rain may bring a bit of green to the low areas. It might look from the truck as though there is enough feed to carry on into the fall.
If you walk through a West Texas pasture in August, the grass will usually show you what is really happening, even if it is not what you want to see. Maybe the old bluestem is thin near the water lot. Maybe broomweed has popped up in a pasture that looked good back in the spring. Maybe ragweed is filling in bare spots, or silverleaf nightshade keeps returning, no matter how many times you thought you had it under control. Most ranchers see these plants and immediately ask, “What do I need to spray?” That is a reasonable question, but it should not be the first one. A better question is, “Why is this weed showing up here?”
Every summer, ranchers look out over their pastures and see weeds rising above the grass and brush shading spots where forage should grow. That’s when the same question comes up: “Do I spray this now, or did I already miss my window?”
In June, a pasture might look good from the road, but it could still be hiding problems.
If you want to really understand your pasture conditions right now, don’t just look at the grass, watch the weeds, too. In May, everything becomes more obvious across West Texas and the Southern Plains. You can see what grew well with early moisture, what got grazed too much, and what’s been slowly going downhill. This is one of your best chances to check pasture health before summer stress hits.
