LITTLE ROCK, Ark. (AP) -- Empty grain elevators surrounded by a swollen White River await a harvest that may never come as floodwaters drown wheat already planted this spring.
Last year, Arkansas produced about 28.7 million bushels of wheat. Now, muddy waters have run through fields for days, taking with it expensive fertilizer treatments already applied to the soil.
Some of the wheat, green this time of year and looking like tall grass, has survived, wheat expert Jason Kelley, of the University of Arkansas Cooperative Extension Service, said Thursday. But grain under water for a week or more likely won't make it.
"You could really tell the plant had been suffering," Kelley said. "They were actually wilted and looked like they were running out of water, but they had no oxygen."
Any real estimate on the damage will have to wait until the floodwaters drain, Kelley said, a process that may take days.
The flooding in Arkansas began with storms March 17 in the Midwest, and federal and state officials have been able to assess the damage only where the water has receded. Thirty-five counties - nearly half the state - have been declared federal disaster areas. One person was killed in the storms in Arkansas, and another remains missing.
Recent heavy rains also flooded parts of other states, including Ohio, Indiana, Illinois and Missouri. The weather has been linked to at least 17 deaths in the region.
The National Weather Service issued a flash-flood warning Thursday for the White River downstream from the town Des Arc, northeast of Little Rock, and forecasters said flooding at Clarendon in Monroe County could be the worst in 25 years.
Residents along the White River National Wildlife Refuge near Clarendon will see water rise a foot a day, said weather service hydrologist Steve Bays.
"One thing that we are trying to do around here is keep people concerned about what's going on but not inflict a panic, and it's a fine line. It certainly bears monitoring by people along the river," Bays said.
With waters still rising under sunny skies, forecasters called for a 50 percent chance of thunderstorms Friday and a quarter-inch of rain or more.
Jaysson Funkhouser, a surface water specialist with the U.S. Geological Survey, said preliminary figures showed that the White River surge from last week's storms and flooding upstream could, in coming days, reach the 100-year flood stage - meaning it has a 1-in-100 chance of being flooded this badly in any given year.
The last flood of similar size was in December 1982, when parts of Arkansas saw more than a foot of rain in a single day. That storm did hundreds of millions of dollars in damage.
Flows on the White River near DeValls Bluff reached more than four times the river's normal speed there, Funkhouser said. But as the river flows downstream, it floods low-lying fields and slows down, he said.
"It's like a huge reservoir," Funkhouser said. "It releases it slower over a longer period of time."
On the Arkansas River, the U.S. Army Corps of Engineers recorded heavy flows Thursday morning at Little Rock, and shipping virtually stopped along the waterway, a major route to the Mississippi River.
"There's some movement, but it will probably pick up as the flows come down probably late next week," corps spokesman P.J. Spaul said. "But that's all depending on the flows continuing to decline."
R. David Paulison, administrator of the Federal Emergency Management Agency, visited areas in Missouri damaged by flooding, even as a new round of rain rolled over eastern parts of the state.
He planned to tour Arkansas communities Monday, spokesman Bob Alvey said. The trip will be Paulison's second to the state in almost a month since he visited Atkins to view damage caused by a Feb. 5 tornado.
In Missouri, the corps said Thursday it stopped the release of extra water into the Missouri River below Kansas City, citing residents worried about more flooding.
The corps said it began holding back releases from tributary dams in the lower Missouri on Wednesday. That move effectively negates releases already put in motion from a dam in South Dakota.
The move will still provide a pulse of higher water needed to prompt spawning of an endangered fish, the corps said.