Grazing System

Grazing System

Grazing System

Article index

  1. Twelve Aprils Dairying
  2. The Herd
  3. Physical Layout
  4. Grazing System
  5. Irrigation System
  6. Waste System
  7. Putting it all together



Supplemental Feeding


Cow Comfort

Cost Effectiveness


A trip to Ireland with a SARE PDP project headed by Steve Washburn changed Tom's opinion about paddock sizes. His 70 acres of grazing used to be divided into 8 paddocks, but now he has 25 paddocks ranging from 2.5 to 3.2 acres that are grazed for only one day at a time. This photo shows re-growth in the foreground paddock while the herd grazes a fresh paddock in the background.

"I used to be opposed to moving fences daily because of the increased labor," he says. " But in Ireland I found out that if you put a herd in 10 acres, they will walk that entire pasture eating only the best forage. That first milking will be great but production will decrease from there, until the herd is moved again."

Tom compares his grazing system to playing chess on a 25-paddock board, with the goal of having something to eat when the herd needs it, but not letting any go to waste. The basic tasks are repeated in each paddock as needed: planting, grazing, no-till planting into a recently grazed crop or baling excess for dry cows and heifers. The decisions of when to do what depend on weather, maturity date of the crop, and how much the cows graze a paddock during the growing cycle of a particular crop.

He gives this example:

"Suppose I plant trudan in a certain paddock early in the spring. I will no-till millet into it during the last few days the milkers graze. After they move off, I will mow and bale the remaining trudan for the dry cows and watch the millet grow until it is ready for grazing."

He stresses the importance of knowing the maturity date of each variety planted.

"Varieties have different maturity dates ranging from 17 days to 120 days," he explains. "The clock starts ticking when you plant. Depending on the crop and the weather, the herd will graze from one to three times. When forage approaches its maturity date, no matter what it looks like, the flavor and nutrients are gone as the protein level drops in preparation for going to seed."

In his experience grazing alfalfa is the exception to the maturity rule. "I don't know how alfalfa does this, but it seems not to change in flavor and nutrition if it is grazed in early bud. During the drought of 2000 I grazed unirrigated alfalfa three times and irrigated alfalfa seven times."

Keeping all that in mind, Tom usually follows the pattern of grazing when a crop is below the knee and baling when it's above the knee. He doesn't see any profit in forcing milkers to graze a taller, tougher, less nutritious stage. "Don't let milk production slide while you wait for the milkers to graze lesser quality forage. Go ahead and bale that paddock for the dry cows and heifers so you can get a re-growth or plant a new crop."

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Throughout the year Tom will plant in succession grazing maize, trudan, millet, small grains, alfalfa and clover, experimenting with new varieties if they seem to fit into his system. Variables such as weather determine that no two years are exactly alike, but on average he makes five to seven plantings a year, seeding six to eight paddocks with the same crop on successive dates.

Since 1988 his most important planning tool has been a piece of notebook paper divided into 12 columns. The columns are labeled January through December, but in Tom's mind they are all Aprils. The columns are divided with two horizontal lines marked planting and grazing.

Planting dates for each crop are marked on the planting line, the first grazing date is marked on the grazing line, with Xs to mark later dates for clipping or baling. A line connects all the dots for that crop, providing a visual time line of its life span in a paddock.

See grazing chart:

chart.pdf 17.00 kB

Finding the right crops can be a bewildering journey through research literature and advertising hype. He constantly educates himself by going to conferences, talking to researchers, visiting other dairies and reading. Managing Cover Crops Profitably is his favorite guide.

"It's practically my Bible," he says. "I can look up different crops and find out what they will or won't do for my soil and my cows. It saves me a lot of experimental planting."
 In general, here's what Tom plants each year:

Corn, specifically grazing maize, is the first crop planted in early spring. Seeded after alfalfa has played out in a paddock, it will flourish in the abundant nitrogen remaining in the soil.

Trudan is a tasty cross of sudan-type grasses that Tom's cows favor over some other varieties such as Sudex/sorghum crosses. The second crop planted in the early spring, it provides good grazing from mid-June until September. Clover or alfalfa are mixed in for added nitrogen as needed.

Millet (different varieties) follow Trudan in the spring to provide for that most difficult grazing period from the dog days of summer through early fall. Tiff Leaf 3 has proved a very palatable, thin-stemmed variety that will wait on the water during times of drought. It was a fortunate choice for the summer of 2000. Clover or alfalfa are mixed in for added nitrogen as needed.

Small grains such as Vitagraze, Florida black rye, Athens rye, Wrens Abruzzi rye all mature at different times and are planted throughout the cool season to give more Aprils. Marshall rye grass is mixed with all the small grains. Clover or alfalfa are mixed in for added nitrogen as needed. 2000 was the first year to plant Black Oats, which Tom heard about at a SSAWG conference. A researcher gave him a bag, which he grew and combined for seed in 1999. Planted in three grazing paddocks for 2000, Tom has been pleased with the impressive amounts of biomass it provided and with the fact that it can be planted a full month earlier than Florida black rye. He intends to increase the plantings next year.

Wheat is the last plant to mature in the spring so it provides two extra Aprils in March and May.

Grazing alfalfa is the star performer on 18 acres. In South Carolina it provides seven months or more of grazing. During the drought of 2000 irrigated alfalfa was grazed seven times and non-irrigated alfalfa was grazed three times. When planting trudan or millet Tom mixes in one or two bags of alfalfa per 10 acres for added nitrogen if the soil has a high ph and is well-drained. If the paddock is located in a low, wet area clover will be planted for added nitrogen.

Clover is planted alone for forage and also mixed in with the trudan, millet and small grains for added nitrogen in paddocks located in the lower wetter areas of the farm. In well-drained fields with higher ph, alfalfa is planted for added nitrogen. Between the crop rotations and manuring, the pastures have maintained productivity for 13 years. Even though soil and tissue samples taken regularly don't show any deficiences, Tom knows some calcium leaves the farm in milk, so he limes half the paddocks every 3-5 years.

The CrustBuster no-till planter makes quick work of drilling seeds into stubble.

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Supplemental Feeding

Supplemental feeding is mainly for energy since the lush grazing supplies sufficient protein. High energy pellets are fed at milking time, approximately 8 - 12 pounds per cow per day. Outside, the fence-line feeder supplies TMR consisting of corn, citrus pulp, soybean meal and on-farm balage.

Deciding when and how much to supplement grazing is the steepest learning curve in the system. It is also the decision that most critically affects profit margin. Tom follows the same method he observed on a tour of Irish dairy farms as part of a SARE PDP grant headed by Steve Washburn of NCSU.

1. Measure the height of the forage in the paddock that is next in line for grazing.

2. Cut a square foot of the forage two inches above the ground to account for the lowest part of the stem that won't be grazed.

3. Dry it (a microwave or conventional oven can be used) and weigh it.

4. Multiply the dry weight of that one square foot by the number of square feet in the paddock to determine how many pounds of usable dry matter content is available in that paddock.

5. Divide those pounds by the number of cows to determine how many pounds each cow will be eating.

6. Use the average weight of the cows and the amount of milk you want each one to produce to figure out how much feed they need. (You may want to refer to your nutrient advisor or feed salesman at this point, until you get used to figuring it.)

7. If that particular paddock's grazing doesn't supply the required amount of nutrients, then make up the difference with TMR.

According to Tom, it is step #7 that sets his system apart:

"If a 100-percent grazier gets in the situation that a particular paddock is not supplying all the nutrients the milkers need, he loses production; but with Twelve Aprils, plugging in that supplemental feed as needed will maintain herd productivity. In the early days of setting up this system, grazing accounted for only about 25% of total nutrients, but as I continue to refine it, I think 50% is a conservative estimate these days. It varies so much depending on the weather, but I have gone as low as 15 pounds of TMR per day with the rest coming from grazing and produced 56-72 pounds of milk per cow per day."

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Four high-quality chargers equipped with lightening arrestors power the fences around and across the paddocks. Three to five strands of high tensile wire are used for the perimeter and two to three strands on the lanes. Temporary cross fences dividing paddocks use just one strand.

Since money saved is money the cows don't have to produce, Tom is always looking for ways to reduce inputs. Instead of paying $3.00 each for movable paddock posts, he has improved upon a homemade design he saw in Ireland. Starting with a 44-inch length of reinforcement bar, a washer is welded six inches from the bottom . White PVC pipe is slipped over the re-bar and stops at the washer. Another washer is welded on top to keep the plastic sleeve in place. A brad holds the insulator to the post. All for 90 cents each.

On the Ireland trip, Tom saw that all-weather travel lanes gave access to the paddocks every day of the year.

"I used to think lanes were an unnecessary labor expense, but now I realize they are crucial in making grazing work for a dairy," he explains. "When a cow walks in mud she puts her foot down in the same place every time she walks to and from the barn, making a deeper hole with each pass. By the time winter is half over their udders are dragging in the mud, putting stress on them and using more energy. Critics of grazing say that walking uses energy that could be put into making milk, but I say walking on good lanes stimulates appetite and makes more milk."

Upon returning from Ireland Tom began constructing his 12-foot wide lanes. While doing so he evaluated different lane-building materials as part of a Southern SARE producer grant project. Of the materials tested, locally obtained medium-grade crusher run, that mixture of sand and gravel used for road beds, is the best for his purposes. It is cost-effective at only $9 per ton and the rounded gravel is easy on hooves. Some crusher run he obtained from Virginia had sharp edges that would make feet sore, so it is crucial to examine samples before ordering. The one drawback Tom has seen in crusher-run is that it needs packing about twice a year with an asphalt packer or to keep the loose texture from making the cows uncomfortable. Under the crusher run is a layer of geotextile fabric, also used in highway construction.

Lime was also tested as a lane material. The fact that it adheres to the hooves was a plus for hoof health and also for letting the cows lime the paddocks, but it depleted the lane quickly. What the cows didn't pack off, the rains washed away, making lime unsuitable for permanent lanes.

Shredded rubber tires were on the list to be tested but at $1000 for 20 yards of lane, they were deemed too expensive to even test. Likewise reconstituted asphalt never made it to the test after a vet advised it would burn hooves in South Carolina's heat.

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Cow comfort

Shade is important to cow comfort and milk production. Tom is fortunate to have ½ to ¾ acres of trees in all but three of his paddocks. In hot weather, early morning grazing is scheduled for the unshaded areas. Forty two free stalls are used for feeding TMR near the milking area. Similar shade canopies of wood or other material could be used in paddocks without trees.

To water his traveling herd, Tom buried one-inch plastic pipe from his well to the paddocks. Water is served in 300-gallon Rubber Maid troughs. Each trough sits on a pad made from geo-textiles, paid for with cost-share from the Farm Services Agency. "This is a little-known but very helpful program that most producers don't take advantage of," says Tom. 'Without those pads under the troughs huge mud holes would develop."

Upon learning that a cow needs 40% of her daily water requirement immediately after milking, Tom installed a 40-foot long watering trough for use when the herd leaves the milking parlor. It replaces a six-foot trough, which boss cows dominated most of the time. The new trough is made from a 20-foot long plastic culvert that was sliced horizontally and welded together by special order at the manufacturer.

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 Cost Effectiveness

Since the switch to grazing, Trantham's Dairy has averaged a net income of about $40,000 a year, compared to less than $16,000 a year for the eight years it operated as a top-producing conventional dairy with a 22,000-pound rolling herd average. Because of reduced inputs, profits began going up even as production fell to 15,000 pounds during his first grazing experiments.

Compared to the days when he used to purchase as many a 17 ingredients for a total mixed ration (TMR) to supplement the silage he stored each year in an $80,000 silo, Tom has documented a 42-percent reduction in input costs during his best grazing year. The number of days grazed and the quality of the grazed forage varies from year to year, depending on weather.

Results from the original Clemson-led SARE research project showed that during the three-year project, an average of 74 cows grazed 689 days out of 945 days for a savings of $15,805 (or 31 cents per cow per day) when compared to his old confinement system. That savings was calculated to include fixed costs such as machinery, labor and fencing. If only variable costs were included, grazing saved an average of 63 cents per cow per day over what it would have cost to feed this herd harvested feed only. According to Tom, his profit margin actually benefited beyond the reported savings due to reduced veterinary and equipment expenses.
 As the 12 Aprils system has been refined and improved, in most years the bottom line has been better than in the research project, leading Tom to think his goal of $60,000 from 60 cows is not far off.

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