Grazing Bites

by Victor Shelton,

Retired NRCS Agronomist/Grazing Specialist 

 Every summer, there comes a point when using the hay mower or bushhog starts to look tempting. A few paddocks may have gotten ahead, some forage is more mature than we would like, seedheads are showing, quality is slipping and the field starts looking like it needs to be cleaned up.

There are times when that is true. Hay has its place, and most livestock operations need some stored feed, especially when fields cannot be grazed or winter feed reserves are short. But on acres where livestock can graze, I have become increasingly cautious about reaching for the mower too quickly.

The question is not simply, “Can I make hay here?” The better question is, “What happens to this field after the hay leaves?” A bale is not just feed; it is fertility, carbon, plant material, sunlight and soil moisture captured by forage plants. When that bale leaves the field, part of that field leaves with it. Nutrients move with the hay, and while some may be replaced later, they do not return on their own.

That is one of the biggest differences between haying and grazing. Haying is mostly a removal system, while grazing, when managed well, is more of a recycling system. Livestock harvest the forage, but much of what they consume returns to the pasture as manure and urine. That return is not distributed perfectly, but grazing usually keeps far more fertility working within the pasture system than mechanical harvest does. Repeated removal eventually shows up as slipping growth, thinning stands, weeds, drifting soil tests and the need for more replacement fertility.

The other thing we remove with hay is cover, and that becomes especially important in July. This is typically the time in which heat builds; rainfall often becomes scattered and cool-season pastures may be slowing down. A clean-cut field might look orderly, but it can leave soil more exposed when shade and residue are worth a lot.

That does not mean we should ignore forage quality. Mature forage has limits, and livestock performance can suffer if animals are forced to consume too much low-quality material without choice. There are times when clipping or haying can reset a pasture, but we should be clear about what we are trying to accomplish. Are we improving the grazing system, or are we just making the field look better from the road? Those are not always the same thing.

Standing forage is not always wasted forage. Some of it is feed, some is soil armor, some shades the ground, and some becomes organic material that feeds the soil later.

That is especially true with bushhogging. Most rotary mowers are not precise seedhead removers and usually remove more than needed. To take off the seedheads, we often end up cutting into forage that livestock could still use, or forage that should have been left as leaf area for regrowth. In the process, we may knock down more usable feed than we realize, lay that material over the remaining canopy, shade leaves that were still photosynthesizing and reduce the very recovery we were trying to protect. If the goal is only to make the pasture look cleaner, the mower may be costing more than it is saving. If you can’t mow high enough to stay out of good grazable forage, then it usually makes more sense to graze it before clipping it.

Seedheads often get blamed for more trouble than they probably deserve. They can reduce forage quality, and when heavy enough, can become an eye irritant if cattle are forced to graze through mature forage at eye level. Still, I would be cautious about overstating that risk. In my own field judgment, I would not consider seedheads alone to be a moderate eye-irritation concern until seedhead production is over roughly 40 percent, with over 50 percent being a higher concern. Even then, seedheads do not cause pinkeye by themselves. Dust, fly pressure, animal susceptibility, crowding around shade or water, and general stress may be just as important, or even more important.

Grazing leaves more options than either haying or clipping. A paddock with extra forage can sometimes be used to slow the rotation, stretch recovery on other fields, provide dry-weather reserve or begin building stockpile. Sometimes we make hay to create winter feed, only to leave ourselves short of standing forage for summer, fall or dry-weather recovery. 

Of course, that must be managed. Leaving animals too long can create its own problems, especially if they stay long enough to start grazing new regrowth. Good grazing still comes back to residual and recovery, because every grazing decision is a root decision in disguise.

That is why I would rather graze excess forage with intention than automatically bale it or bushhog it. Shorter grazing periods, higher stock density for a brief time, and adequate recovery afterward can turn some of that extra growth into animal gain, manure, urine, trampled residue and future soil function. It may not look as clean as a hayfield or a freshly clipped pasture, but the field may be better off for it.

There are still good reasons to make hay. If a field lacks livestock water or fence, or if livestock must be hauled just to graze it, hay may be the practical choice. If forage is truly surplus and winter feed is short, making hay may be necessary. If a pasture has become too mature and grazing cannot bring it back into balance, a timely cutting may help reset it. If a field is hard to access with equipment, then it will also be hard to put nutrients back on it. That usually makes it a better candidate for grazing than haying.

Before baling or bushhogging a grazable acre, walk it and ask a few questions. Could this forage be grazed instead? Would it help extend recovery somewhere else? Is this field strong enough to handle nutrient removal? Will I replace what leaves? Am I cutting off leaf area that should be left for regrowth? Am I making hay because I need feed, or because I want the pasture to look tidier?

Hay has value, but hay also has cost. Bushhogging has a cost too, even when the forage stays in the field. If we clip too low, too late, or without a clear purpose, we may be wasting feed, covering green leaves, slowing regrowth and spending time and fuel to make the field look better without making it function better.

On acres that can be grazed, that should count for something. I am not against hay, and I am not against clipping when there is a good reason. I am against taking hay from grazable acres, or mowing usable forage into the ground, without asking what the pasture loses in the process. Sometimes the best hay is the hay you make, while other times, the best hay is the forage the livestock harvest themselves while it is still rooted in the system.

It is not about maximizing a single grazing event but about optimizing the entire grazing season. Keep on grazing.