He's Also an Otolaryngologist

Tree Farmer Develops Irrigation Technique

By Ed Albanesi Editor

Farmers have always been an efficient bunch. They operate efficiently because margins are often narrow and inefficiency can compromise any chance they may have at turning a profit.
 

And farmers also have a love for the land and all the natural resources that make up the environment in which they grow products that feed and clothe our people and help beautify our living space. As the bumper sticker says, "Farmers were the first environmentalists."

So it should not be a surprise to anyone that Florida farmers are among some of the brightest innovators when it comes to efficient use of our natural resources. Case in point: Dr. Dick Holloway, a graduate of both the University of Florida and the Duke University School of Medicine.

Holloway, a practicing ear, nose and throat surgeon at Orlando's Florida Ear Institute, also owns and operates an ornamental tree nursery in Leesburg. He produces several varieties of trees, including live oak, crape myrtle, ligustrum. cypress and magnolia. The young trees are grown in various-sized containers and are irrigated using three different methods.

Holloway uses overhead irrigation on about four acres, low-volume spitter irrigation on 20 acres and currently has about three acres of potted trees irrigated by his patented flood plain system.

Holloway's "Flood Plain Irrigation and Recycling System" consists of a polyethylene-lined flood plain, dikes and pipes, pumps and a water collection reservoir.

The system divides land into sequential sculpted flood plains with a diking system that permits flooding for specific time periods. After the flooding sequence takes place, the water is drained back into the originating reservoir.

According to Holloway, his flood plain system uses about one-fourth of the amount of water needed when overhead irrigation is used. Even the spitter irrigation that Holloway uses with his 15-gallon containers will consume about two-thirds more water than his flood plain system. But the savings don't end there.

"Even more water is saved because the trees grow faster," says Holloway. "Every root in the pot is touched by water. You don't have the dry spots that are common with other irrigation methods."

Holloway, a Lake County Farm Bureau member, says the uniform water supply is only one reason why he is seeing an average one-third faster growing rate with flood plain irrigation.

"Heat is reflected off the polyethylene liner which results in a six to eight degree increase in temperature," says Holloway. "That, combined with the photosynthetic properties of the reflected light, results in faster growing rates. Our ligustrums grow 50 percent faster."

According to long-time Holloway family friend and collaborator Dr. Grant Proulx, the reflected light has another benefit. "The ultraviolet light works as a pesticide and helps to control the aphids which take up residence on the underside of the leaves," Proulx avers.

A senior research chemist with Dupont Chemical Corporation, Proulx studied inorganic chemistry at Berkeley and has concentrated much of his research on polymer chemistry.

Holloway says his system also saves considerably on labor costs. "Our system is automated to the point where there is minimum labor associated with it," says Holloway. "Many nurseries spend a lot of labor time on irrigation. For example, about 10 percent of our work force time is devoted to irrigation in places where we're using traditional irrigation methods."

Overall operation and maintenance costs, according to Holloway, are about 25 percent less with the flood plain system. He says that electric costs alone are about 20 percent lower.

Holloway has received two grants from the St. Johns River Water Management District to help with the construction of his system. The first grant for $50,000 was issued two years ago and helped Holloway build his first sloped flood plain system.

He's receiving another $20,000 grant this year that is helping finance the construction of a flat flood plain system that uses a slightly different mechanism to move water through the flood plains.

Both the sloped and flat constructions are closed systems resulting in "zero" runoff. "We filled our reservoir one- third full two years ago by pumping ground water into it. Since then, the only water that's been added to it has been rain," says Holloway.

Don Brandes, the water management district's water conservation program manager, says that Holloway's system is very efficient. "It's a state-of-the-art water recycling system," says Brandes.

According to Brandes, the water management district will provide cost sharing to others who can come up with similar water conserving methods.

Holloway says that he hasn't experienced any problems relating to water quality. He says the nitrate concentrations in his six-million gallon reservoir are low enough to meet drinking water standards. He raises tilapia and catfish on site and uses them to stock his reservoir.

"The tilapia and catfish consume algae and grow like weeds. In turn, we have wading birds, eagles and ospreys which eat the fish. We haven't had any problems with fungi or diseases," says Holloway.

Another advantage to Holloway's system is that the polymer linings in the flood plains and reservoir prevent fertilizer and other chemicals from leaching into the underlying soil, and ultimately into the ground water.

Holloway hopes to market his system both domestically and internationally over the next couple of years. He says that the patent he holds is a "system and method" patent that covers any flood irrigation system that uses recycled water.

"My system will save an average of four million gallons of water per acre per year," declares Holloway. "When you pay for water, as they do in California and in other places, the savings in water can translate into savings of up to $25,000 in yearly per-acre costs. We are currently looking at markets in the western United States and in Middle Eastern countries."

Interestingly enough, Holloway's first efforts with this genre of irrigation involved experimentation with "baby" swimming pools and potted tree seedlings. "The one thing that I learned from those early experiments is that the technique saved some water," says Holloway. "And although Florida is, comparatively speaking, a water-rich state, other factors make flood plain irrigation very applicable in Florida."

Those factors, according to Holloway, include Florida's regulatory climate, its variable weather, its growing population and (Holloway's contention) that Floridians will soon be paying a fee for their water.

So if, as the old Latin saying goes, "Necessity is the mother of invention," Holloway has joined an ever-growing group of farmers who are proactively reclaiming control of their destiny by discovering ways to produce more while consuming less.

FloridAgriculture, July 2000. All rights reserved.