87 percent of the U.S. water supply starts from forest, ag lands

By STEVE BROWN

Capital Press

The U.S. has underthought, underinvested in agroforestry, Kathleen Merrigan, deputy secretary of the USDA, said as she opened a seminar May 25 in Washington, D.C.

"Agroforestry in America," whose opening session was webcast, featured farmers and landowners who "incorporate trees with other plants or livestock to achieve economic benefits," the working definition of agroforestry. The practice is designed to sustainably produce food, feed, fiber and energy, while improving wildlife habitat and soil, water and air quality.

Merrigan said the Interagency Agroforestry Team has been charged with "developing a national strategic framework" to help decide where the USDA focuses its assets and attention.

USDA Secretary Tom Vilsack, Merrigan said, considers forests critical assets in the U.S. "He wants an all-lands approach" involving state, tribal, private and federal lands. "Threats to ecosystems don't respect property boundaries," she said.

Much of the government's concern has to do with water quality, she said, because 87 percent of the U.S. water supply starts from forest and ag lands.

Gene Garrett, director emeritus of the University of Missouri's Center for Agroforestry, described five different variations on agroforestry:

* Alley cropping, in which rows of trees are intercropped with a shorter-term cash crop;

* Silvopasture, incorporating trees into livestock operations;

* Riparian buffers, which Garrett called "the last line of defense for waterways";

* Windbreaks, which stretch 175,000 miles in the Midwest alone; and

* Forest farming, which involves thinning stands of trees to allow more light for a cash crop on the forest floor.

Many farms -- especially those producing less than $250,000 a year in farm sales -- are "not making it," Garrett said, and he sees agroforestry as a solution. Small farms especially can design specialty crops into agroforestry sites, tapping into the buy fresh, buy local movement.

He described a few models:

* Chestnuts -- The U.S. imports 2 million pounds a year, mostly from Europe. An acre of trees can produce 2,000 pounds by age 10.

* Pine straw -- Mining the needles of pine trees can yield 100 to 250 bales per acre every other year.

* Mushrooms -- Morels are very popular, he said, and a black truffle operation can yield 50 pounds per acre, bringing as much as $400 a pound.

* Woody biomass -- Alley cropping with a fast-growing tree such as the willow can yield 5 to 10 green tons per acre per year.

Incorporating trees into buffers, he said, helps regulate sediment better than grass only, and it has been proven to filter out more nitrogen and phosphorus.

"It's no longer just anecdotal," Garrett said. "Science has finally caught up with the practice of agroforestry."

Planting poplars or cottonwoods at the base of a paddock keep veterinary antibiotics out of waterways. Microbial organisms in the roots produce an enzyme that breaks down sulfamethazine.

Trees planted around confined animal feeding operations provide odor abatement and energy savings, as well as improving air and water quality.

"The national strategy is to revitalize rural America," he said, "which includes adoption of agroforestry techniques that yield sustainable profits, address environmental issues and create new avenues of farming."

Cooperation

Six branches of the USDA are involved in the Interagency Agroforestry Team:

* U.S. Forest Service

* Natural Resources Conservation Service

* Agricultural Research Service

* National Institute of Food and Agriculture

* Farm Service Agency

* Office of Environmental Markets

Rounding out the team:

* National Association of State Foresters

* National Association of Conservation Districts

Online

National Agroforestry Center: www.unl.edu.nac