WALLA WALLA -- We know terrorists can blow things up and kill us in a single blast.

But what if they went after our food and economy?

Amber waves of grain paint a pretty picture, but the Department of Homeland Security warns: those fields are vulnerable to attack.

It's called Agroterrorism.

The Department of Homeland Security wants our farmers ready.

Monday, they helped them fight those food fears with a series of seminars.

How likely is this to happen?

The feds said no one is necessarily sneaking around from farm to farm and contaminating crops.

But the possibility of a threat is a real one.

It's as damaging as Anthrax, worrisome as W.M.D's.

And this threat could cripple our local economy.

Agriculture impacts more than 60 percent of Washington's economy, and it's here in Eastern Washington.

So if there is an attack, it could have major effects.

"You should be alert and just keep an eye open," owner of Cavalli Onion Acres Ben Cavalli said.

The threat is called Agroterrorism.

It's a subset of bio-terrorism, defined as "deliberately introducing animal or plant disease with the goal of generating fear, economic loss, or undermining economic stability."

"It's a concern, but again you can't put up a fence around a field of onions," Cavalli said. "Somebody can sneak into your farm at night and you'd never know about it."

Cavalli's seen the devastation of disease on his farm.

Walla Walla sweets are particularly vulnerable to virus and that's without a terrorists help.

"It lost 17 acres of my winter sweets due to the thrips and the virus," He said.

And it's not just field crops we should be concerned about, according to the Feds.

Agents claim the greatest threat is to livestock.

"You only get paid once a year, you work all year and you lose that crop it's really hard on you," Cavalli said.

Cows, for instance, are often in confined locations and are routinely transported, easily exposing the animals to terrorists who could spread the diseases like mad cow.

"I suppose this day and age, anything's possible," Cavalli said.

Agroterrorism experts are especially concerned about the introduction of foot-and-mouth disease and mad cow into the food supply.

Foot-and-mouth is 20 times more infectious than smallpox.

People generally cannot contract the disease, but animals can spread it to other animals if they're within 50 miles.

The Feds said the training will help farmers detect terrorism and prepare "response teams."

Classes are free.

There are two remaining classes taking place this week:

"Principals of Detection and Diagnosis - Strategies and Technologies"
WHEN: Tuesday, February 5, 2008.
WHERE: Oregon National Guard Armory, Hermiston, OR
TIME: Workshop from 9 am - 3 pm

"Principals of Preparedness for Agroterrorism and Food System Disasters"
WHEN: Wednesday, February 6, 2008
WHERE: Umatilla County Justice Center, Pendleton, OR
TIME: Workshop 9am - 4pm