Irrigation, conservation and self-promotion

Photos by Don Dale.
Manufacturing his own equipment, Howard Wuertz uses combinations of root pullers, disks, bed rollers, power mulchers and specialty machines to reduce tillage and the number of passes a tractor has to make over drip-irrigated fields.

To call Howard Wuertz a self-promoter would be stating the obvious. Then again, as one of the pioneers of drip irrigation on crops in the United States, he had to be a promoter at a time when selling drip to farmers was an outlandish and risky idea. He’s proud of his role in the futuristic world of low pressure irrigation and conservation.

This grower of vegetables, cotton, grain and many other crops on subsurface drip tape, as well as the inventor of the many tools required to inject it and till the ground over it, is now 82 years old. He’s still an advocate and leader of the irrigation conservation movement from the office of the family’s Sundance Farms in Coolidge, Ariz.

Furthermore, with his son Dave leading the charge, the family farm of 3,200 acres is farmed solely utilizing drip tape lines. Wuertz, who has been farming in Arizona since 1951 and in this location for 45 years, has become a manufacturer and purveyor of equipment engineered for the Arizona Drip System method of farming over drip tape. It is used exclusively on this farm, and on farms across the nation.

“I just got our fifth patent for no-till equipment,” says Wuertz, who notes that he was compelled to look hard at drip 25 years ago for two primary reasons. The first was that he was involved in early projects such as bringing the Central Arizona Project and its Colorado River water to the state, as well as the formulation of the 1980 Groundwater Management Act which regulated water use. He realized that the era of cheap and bountiful water was over, and farmers had to find ways to conserve and learn to grow crops in a water-efficient way.

This peel-off disk, one of five patents garnered by Sundance Farms, is used over drip tape to provide an almost no-till crop of watermelons.

The second reason was that the sandy loam soils in Coolidge would not allow the Wuertzes to efficiently grow row or forage crops, even utilizing other efficient irrigation methods such as basin irrigation. He wanted to find a way to cut water usage from the average of 7 to 8 acre-feet consumed by most crops, and if possible raise yields while doing so. At that time there weren’t many commercial vegetables being grown in this cotton/small grain area.

“My first drip installation was in 1976,” Wuertz recalls. He had heard about the methodology, primarily being used by Israeli growers, and he wanted to try it. “I put in 5 acres. My first crop was sugar beets.”

He hasn’t looked back. That first test was with surface tubing, but he found it unsatisfactory and graduated to subsurface tape. He first established a field with tape in 1980, but found that there was no complete system for injecting it underground or tilling above it. So he used local resources to gradually design and build his own system, which now consists of several pieces of equipment and is sold under the Arizona Drip Systems name. Now, using proprietary machinery such as tape injectors and extractors as well as tillage equipment, his family can grow crops for years over its “permanently” buried tape.

“We couldn’t find a tape injector that would put the tape deep enough,” he recalls, so he designed and built one that would not only do the job, but also would allow for splicing the long rolls of tape right on the deck. Now he builds and uses an injector that lays six rows of tape at a time.

The tape is buried a foot deep, and that suffices for most any crop, being deep enough to soak the roots and yet close enough to the surface so that no other irrigation is needed to germinate seeds. When it is necessary to sprout seeds, beds are worked down so that the soil surface is 8 to 10 inches deep. He also helped develop the elaborate pump and filtration stations needed to deliver clean water through the tape. Stations on Sundance Farms now water up to 400 acres each.

The use of subsurface drip tape seems so intuitive now that it is being used all over the world, but at one time it was difficult for farmers to conceive of it being practical. Sundance Farms uses, and sells, Netafim tape anywhere from 6 to 25 mm in thickness, preferring the 10 to 13 mm for its own uses. That will take a beating, including driving heavy combines over it, and has proven in Coolidge to last over 20 years.

Arizona Drip Systems buys components for its proprietary tillage equipment and assembles them on the farm.

“The life of them is indefinite,” Wuertz says, but proper maintenance is required. The points of maintenance that are emphasized on the farm start with filtering the water to avert clogs. Also, the water is treated with sulfuric acid to prevent calcium and magnesium deposits and to lower pH to about 7. In addition, chlorine is added through the fertigation system in order to stop organic contaminants. That, plus maintaining tape pressure at 12 to 15 PSI, will keep tape efficient for a long time and reduce the cost of replacement. Most nitrogen fertilizer is added through the tape, but phosphates can lead to clogging so it and other nutrients, including micronutrients required for veggies in central Arizona such as zinc, manganese and iron, are applied preplant or in foliar feedings. Side-dressing complete fertilizers is also common.

That doesn’t mean that other vegetable growers don’t use drip tape differently. Wuertz points out that California growers use it in many ways. “You wouldn’t think of growing tomatoes in the great state of California without tape,” he proclaims, and strawberry growers may use it near the surface under plastic mulch and tear it up after one crop. It is cheap enough to be used this way in high-value crops.

This is the way the development process went for all of the equipment that Sundance had to build to get the job done with a new irrigation management system. Much of it was devised to allow the farm to double or triple-crop. He now is able to grow sequential crops of cotton, small grains and seedless watermelons without ever moving the tape, and he has often doubled yields while doing so.

Dave, Howard’s youngest son, has now taken over the job of growing the crops—and is also president of Arizona Drip Systems—and he says the system has allowed him to make seedless watermelons about half of the farm’s gross sales. He grows about 500 acres of melons out of the 3,200 every year, so the vegetable crop more than pulls its own weight. He has grown many other vegetable crops, from broccoli to sweet corn, over the drip tape, but because marketing it from this isolated location has been a problem, he sticks to seedless watermelons for now.

“Most of the drip irrigation in Arizona is in cantaloupes or watermelons,” Dave notes, and both crops are ideally suited for subsurface tape. He grows seedless watermelons in two ways. One is to use transplants in March for harvest in June, and the other is to direct-seed in May for a Labor Day market. Black plastic mulch may be used on some acreage to heat up the soil for early planting.

Using drip tape, the farm averages about 45 tons of watermelons on less than 36 inches of water. That is “basically” a no-till crop, Dave says. If planting behind cotton and using transplants, he will use a Sundance root puller to get up the cotton roots, disk and power-mulch in one operation with equipment mounted on front and back of the tractor. If seeding melons, he will use a Sundance “peel-off” disk to prepare the field in one pass. The planter will be mounted on the back of the tractor for a one-pass operation over, say, a harvested barley field.

On a $3,500 budget for watermelons, Dave says most of that money is used for seed, chemicals and harvest. Water costs are cut to a minimum. This same type of operation, and the same drip tape, can be used for a crop of milo maize planted behind wheat. Cotton is still a big crop on the farm, and it also is grown over drip tape.

Howard Wuertz was a pioneer in the use of subsurface drip tape at his Sundance Farms, and his son Dave now farms 3,200 acres with tape as the sole irrigation method.

Currently, Wuertz says, the farm uses about 3 acre-feet of water per year for all crops, less than half the historic consumption in this area. In addition, Arizona Drip Systems sells equipment to growers from California to Georgia, allowing them to install drip tape as well as till and plant over it. Arizona Drip Systems hires one man to do the assembling of its equipment, having the components manufactured by a firm in Texas. Drip tape can even be used in some tree crop and nursery settings, and with proper row spacings it can be planned into settings as varied as forage crops and wheat or barley. Go to to get more information.

Howard Wuertz still promotes the use of the Sundance system, because the company sells the tape and its equipment, and will even install it for clients. It will go so far as to design and manufacture special equipment for special jobs. He maintains that the future of vegetable production in America—given the increasing scarcity of water and the plethora of competition from abroad—will have to involve drip tape.

“It’s very gratifying to me” that his early and continued work on this system has made agriculture a continuing enterprise in these United States, he says. He will more than likely be promoting it until he’s 102.

Don Dale is a freelance writer and a frequent contributor. He resides in Altadena, Calif.