Although he lives in a state with an average annual rainfall of 40-42", Bob Fry irrigates his pastures every growing season.
“We usually have adequate rainfall, but the proper timing of that moisture is critical,” says Fry, who, with partner Judy Gifford, owns St. Brigid's Farm near Kennedyville, MD. He's also a veterinarian and nutrition consultant.
“Our primary goal is to produce the maximum amount of grass we can,” he says. “Irrigation eliminates our drought risk and ensures a good supply of high-quality, low-cost forage.”
Fry and Gifford practice seasonal calving and management-intensive grazing. Their 71-cow herd of registered Jerseys has a rolling herd average of over 21,100 lbs of milk and 910 lbs of fat.
The partners installed the irrigation system in 1998 at a cost of $30,000 and have used it every year since. It consists of a traveling gun, reel and buried water line. The initial price tag also included the cost of drilling a 110'-deep well.
Since 1998, Fry and Gifford have applied an average of 5.1 million gallons of water per year to 55 acres of pasture at an annual cost of $71/acre. That includes an average of $16/acre for electricity and $55/acre in depreciation costs.
Pumping irrigation water helps fend off summer slump.
“The water helps prevent the grass from going dormant during drought stress,” says Fry. “We're able to graze perennial ryegrass straight through the summer.”
It helps them make the most of their fertilizer dollars, too.
“We move the reel and traveling gun to the paddocks that have just recently been grazed and sometimes right after they've been fertilized,” he says. “That helps incorporate the fertilizer into the soil.”
The fertilization program consists of applying a combination of ammonium sulfate and 30% liquid nitrogen three or four times per year. About 40 lbs/acre of nitrogen are applied each time.
The St. Brigid's cattle graze white clover mixed with a perennial grass, such as ryegrass, orchardgrass or endophyte-free fescue, from April to mid-December. During the grazing season, they're supplemented with a fortified grain mix. In winter, corn silage and baled hay take the place of grazed forages.
The cattle are usually moved to a fresh paddock after every milking. In some cases, the paddock layouts allow for 24-48 hours of back grazing before the cattle are moved to the next paddock.
Paddock sizes vary from just ¼ acre in early spring to 1 acre or more in summer. Excess pasture is used for making two cuttings of hay in big round bales.
To keep the forage in its most nutritious vegetative state, the paddocks are grazed close. Perennial ryegrass can be grazed to just 1”; fescue and orchardgrass, to 2-3". If the forage isn't grazed close enough, it's mowed.
“If you can gauge how much to give the cows, they'll do the work for you,” says Fry. “But if you overfeed them, you need to clip it off.”
When the Maryland heat gets too intense for the cattle, they're able to seek shelter in the barn and/or under a shade tarp.
Manure collected during winter and at is stored for later application on neighbors' fields. Gifford and Fry don't apply it to their pastures for a couple of reasons.
“Cows don't graze very well on fields that have had significant amounts of manure applied,” says Fry. “And if we were to spread that additional manure, we eventually would be in violation of our phosphorus-based nutrient plan.”