As we get into the hottest, driest days of the year, pastures can suffer. Rocky Lemus, Extension forage specialist with Mississippi State University, outlines a few critical management practices that can help growers keep pastures productive during the summer months. 

1. Fertilize 

“As we get into early July, it’s time to think about putting out some nitrogen on pastures before we get into the really hot weather of late July and August. By then, plants are not as efficient at utilizing that nitrogen. If you can apply nitrogen in early July, you’re going to be ahead of the game.” 

“I usually recommend about 30 units of nitrogen. That should be efficient for mid-summer. It is very important to emphasize that if you are going to fertilize a pasture with nitrogen, choose a source that’s not so volatile to the environmental conditions that we have in the South. We’re seeing days with high humidity and high temperatures, so you’ll see more volatility in the nitrogen you’re trying to apply. I would recommend avoiding urea-based products because you could see a lot of losses from volatilization. I would also recommend not using a liquid nitrogen like urea ammonium nitrate which is a 32% nitrogen solution. A liquid nitrogen when applied to grasses in the middle of the summer is very caustic. Instead of helping the plant, it burns the tissues of the leaves. It sets back that grass about two weeks from regrowth and utilizing that nitrogen, plus it’s very highly volatile.” 

“If producers can find ammonium nitrate that would be the best source, but with regulations it’s hard to find it anymore. If they don’t have ammonium nitrate, they can try ammonium sulfate, which is another substitute for these situations.” 

2. Scout for weeds 

“This is the time of the year where you start seeing a larger spectrum of weeds in your pastures. Scouting is very essential to know what weeds you have and will allow you to find a broad-spectrum target herbicide to control those weeds.”  

“This time of year, we see a lot of horse nettle, which is a major issue in pastures in the South, and also dog fennel. Those are easy to control if you use a target product like a Grazon Next, which is aminopyralid plus 2,4-D. There’s a new product in the market from Corteva which is called Duracor. It is a combo of aminopyralid plus rinskor. This product does a great job with horse nettle and dog fennel and also controls other broadleaf weeds in your pastures.” 

“Of course, when doing weed control, always read the labels and pay attention to use rates and grazing restrictions associated with the herbicides.” 

3. Rotation, rotation, rotation 

“It’s important to think about rotation at this time of year. Even if we’re dealing with warm-season grasses in pastures, they still need a recovery time. If you can rotate cattle from pasture to pasture that would allow these grasses to rest and recover faster and have better nutritive value.” 

“I tell producers to rotate every 7 – 10 days. Sometimes we’re dealing with producers who are not full-time farmers. They have a job somewhere else. In those situations, a seven-day rotation is good because you can move the animals on a weekend. Also, make sure you’re allocating 1.5 acres per mature animal (1,000 pounds) if doing this type of rotation.” 

4. Beware of forage hazards 

“As we get into hot dry part of year, if you’re using any summer annual grasses like pearl millet, sorghum sudangrass, or forage sorghum, be aware that under drought conditions these summer annual grasses tend to accumulate nitrates. That can be very detrimental to the livestock, and you can lose cattle very quickly. If you’re in a situation like that and are going to graze summer annual grasses, make sure you maintain them at 6 - 8 inches of stubble height because most nitrates are going to concentrate at the bottom part of the plant. If you’re in a drought situation, for prevention it would be good to take a sample for a nitrate test before you put those animals to graze in those pastures to make sure the nitrates are at safe levels. A forage sample with a nitrate reading levels that are less than 5,000 ppm (0.5%) are considered safe and above 15,000 ppm (1.5%) are very toxic.  Nitrates levels between 5,000 and 15,000 ppm will required adjusting how much forage are provided to the livestock.” 

“I get questions about dallisgrass, and dallisgrass is a good forage for us. One of the issues with dallisgrass is there’s not seed available in the market for establishing it in pastures. What you have will be something that is native. If you want to have a pure stand of something other than dallisgrass, it’s hard to control.” 

“One of the problems that we only see with dallisgrass is that the seed heads can be prone to have a fungus. That fungus can cause staggers in cattle. If you have dallisgrass pastures and see you have a lot of seed heads out there check for the fungus. The disease first appears as a dark, sticky substance, and as it grows will make the seedheads look yellow to dark grey. If you have it come in and clip your seed heads. Set your mower really high because all you’re doing is clipping the seed heads so the cows can graze the rest.”  

5. Start thinking about fall 

“It’s time to start thinking about transitioning from summer to fall. In areas where tall fescue is an option for you, start thinking about preparing that tall fescue in late August or early September for stockpiling, so you can utilize it as soon as you get out of warm season grasses in October.” 

“If a producer is using winter annual grasses like ryegrass, wheat, cereal rye or triticale, now is the time to plan ahead. Seed prices may be cheaper now than when you get into August and there is high demand for buying seed. It could save you some bucks if you have a more active approach to fall grazing.”