Optimism translates into good year as annual show winds up.

Farmers attending the last day of the World Ag Expo on Thursday said higher milk and cotton prices are boosting the mood in farm country, and exhibitors said they can tell the difference.

"This is a better year by far," said Lynn Tjaden, regional sales manager for Dairymaster USA Inc., based in Hamilton, Ohio, which makes milking equipment. "The first half-day this year was better than all three days last year."

"I've seen a lot of smiles on the faces," said Scott Rasch, a project manager for Case IH, which makes tractors. "Commodity prices are driving the mood."

"I'm optimistic," said cotton grower Toby Collins of Wilcox, Ariz., who has seen the price of cotton jump from $1.20 a pound in 2009 to $1.70 a pound for May futures contracts. "We've got a couple of years here where we'll have some really good times for agriculture."

Collins -- shopping for plowing gear -- said he presold some of his 2011 cotton crop, and hopes to lock in an even better price for the rest.

But the news isn't all good: Rising oil prices are causing fuel costs to go up, he said.

Meanwhile, dairy farmers are heaving sighs of relief over higher milk prices, which are up 60% since last year.

"We're starting to get a little bit more," said dairyman Richard Westra of Tulare.

For the past two years, dairy farmers have been squeezed by high feed costs and low milk prices. They're still jumpy about the fuel and feed costs, "but we're better off having the higher price" for milk, said dairy and cotton grower Mark Watte of Tulare.

Attendance figures for the farm show were not available Thursday, but CEO Jerry Sinift of the International Agri-Center, which holds the World Ag Expo, said "the parking lots were full for the first time in a few years."

Another bright spot in agriculture is the market for organic fruits and vegetables, which has been growing about 10% to 15% a year, said organic almond grower Mike Barnard of Turlock.

Barnard was at the farm show to shop for something that kills weeds yet still qualifies as an organic farming technique. He said he might have found it in the Weedtechnics machine, which sprays weeds with steam to kill them.

The appearance at the World Ag Expo of the device -- designed in Australia and made in Redlands in Southern California -- could signal an improved overall economy. Company president Jeremy Winer of Sydney skipped the farm show last year because the economy was so dire.

But he's glad he came this year: "We've got four times as many interested leads as I expected to get."