Hurricane Frances (search) may have damaged $800 million to $1 billion worth of Florida agriculture, according to preliminary estimates by the state Department of Agriculture.

Agriculture officials were still assessing the damage and said they wouldn't have solid estimates until later this week.

But nearly half the farms in Florida, or about 20,000 farms, were in the path of Frances, said Liz Compton, a spokeswoman for the Florida Department of Agriculture (search). "Some weren't impacted greatly. For others, it was 'Oh my god,'" she said.

The storm may have destroyed or damaged two-thirds of Florida's $205 million grapefruit crop, caused $350 million to $400 million damage to Florida's $1.5 billion nursery business and caused $200 million losses to the state's timber industry, according to rough estimates, said Compton.

"We know that on the citrus side, that the fresh fruit industry is probably looking at some severe losses," said Agriculture Commissioner Charles Bronson, who planned to tour ravaged agricultural areas on Wednesday. Most of Florida's orange crop is turned into juice or frozen concentrate, but the rest is sold as fresh fruit.

Frances made landfall in the heart of the Indian River Citrus District (search) on the Atlantic Coast where most of Florida's $205 million grapefruit crop is grown. Because it's larger, grapefruit is more vulnerable to high winds than oranges.

"On the grapefruit side, a lot of people think that they may lose their whole grapefruit crop," Bronson said.

Florida produces three-quarters of the grapefruit in the United State, which is the world's largest producer of the fruit. Half of Florida's grapefruit is turned into juice, while the other half is sold as fresh fruit with most of it shipped to markets abroad.

"Some growers are reporting to us that they lost 50 percent to 100 percent of their fruit," said Casey Pace, a spokeswoman for Florida Citrus Mutual, the state's largest grower's group.

Doug Bournique, executive vice president of the Indian River Citrus League, said this year's grapefruit crop isn't a total loss. The harvesting season begins next month.

"There is still plenty of crop on the trees," said Bournique, who drove through groves in Indian River County on Tuesday.

Bournique said he had seen little injury to trees, which was a problem in southwest Florida after stronger Hurricane Charley tore through orange groves there three weeks ago. Tree damage could hurt growers in future seasons since it takes five to seven years for new trees to bear fruit.

"The trees that have seen damage were trees that were old," Bournique said.

The damage inflicted by Frances may not be over. Standing water has flooded many groves.

"If they do have trees that are soaking in water, the growing fruit will suck up so much water that it will split the fruit," Bronson said. "Even the fruit that is left on the tree may not be pickable."

The flooding also affected the state's cattle industry, which reported 20 animals dead from Frances. Tens of thousands of gallons of milk had to be dumped from processing plants because of power outages.

"There are a lot of cattle up to their middles, (their bodies) almost in water, trying to find high ground," Bronson said. "In the middle of high ground, they're also running into large amounts of fire ants which are also causing problems."

The flooding also likely damaged crops planted in Palm Beach County.

"I have not seen this much water statewide in my lifetime," Bronson said.