By VICKI JOHNSON
Ohio Correspondent

LONDON, Ohio — Biodiversity is the key to a system that may allow farmers – and even people with limited acreage – to earn up to $90,000 per acre, according to Joe Kovach, head of The Ohio State University’s Integrated Pest Management program.

During a program in the Small Farm Center at the OSU Farm Science Review in London last week, Kovach explained his experiments with polyculture systems that grow a variety of fruits and vegetables, rather than the traditional monoculture crops. Crops of various heights are intermixed within rows to provide a diverse biological community.

“They have a lot of perennial plants. They have a lot of flowering plants,” he said.

Kovach’s goal is to earn $10 per foot per row from his plots by mimicking nature. “With a goal of $10 per linear foot, we’ve got to be productive,” he said. “We can’t mess around.”

Kovach said he has paid off the $25,000 initial investment from the crops it has produced. Last year, he harvested $8-$9 per foot of row of strawberries, and was getting $26 per foot of row of grape tomatoes – three to four times the produce of standard tomatoes for the same amount of energy input.

Kovach is testing four designs at the Ohio Agriculture Research and Development Center’s Wooster campus. The first has solid rows that each contain a different type of plant, while the second design mixes more than one crop within a row but keeps the high and low crops together.

The third plot mixes plants within rows and also alternates heights within the row in a “checkerboard” system. And, the fourth design adds raised beds with mixed rows planted within.

He said raised beds are the most productive of the four modular designs. Landscape cloth has reduced the amount of labor needed for weeding. The raised beds gained a 25 percent harvest advantage in most cases, he said.

Another addition to the experiments in 2007 was high tunnels, or plastic greenhouse-type structures open on both ends.
“Things grow better in the high tunnels,” he said. He cited less wind, more shade and moisture control as three of the reasons.
The system is based on three concepts, he told a standing-room-only crowd under the tent.

One main point is spatial diversity, or planting both tall and short plants in the same plot of grounds. For example, dwarf peach trees might share a row with strawberry plants.

The second is genetic diversity, or planting a variety of plants, both perennial and annual. The third concept is temporal diversity, or plants that flower early and some that flower late, as well as some that can be harvested early and some that are harvested later. He said he plants three varieties of apples, for example, for early, mid-season and late harvest.

Kovach’s four designs incorporate apples, peaches, snap peas, tomatoes, strawberries, blueberries, raspberries and edamame soybeans, among others.

In his experiments, he said pests are not a large problem because of the biodiversity. Most pests rely on one form of food and feed down rows.

“Insect pests seem to move down rows,” he said. “So if you’re an apple pest, you might stop at the peaches. A peach pest might stop at the raspberries; a raspberry pest at the blueberries. And so forth.”

He said the Japanese beetle has been the main problem, however, because they aren’t picky about the type of food they eat.
“The high tunnels really keep out the Japanese beetles,” he said.
Fertility is also an important concept.

“I worship at the church of compost,” Kovach said. Compost is important because it allows the slow release of nutrients. “Go with a light touch on your synthetic fertilizer.

“If I didn’t have to worry about Japanese beetles, it would be heaven out there,” he added.