WASHINGTON (AP) _ Ah, the natural, exotic aroma of wild rice as it cooks with freshly bagged duck, pheasant or quail.

Only thing, says the Agriculture Department, wild rice ''is usually not wild and it's definitely not rice.'' What then?

''Wild rice is really a grain more akin to oats than rice, and most of it is now cultivated in commercial paddies,'' says a report by the department's Economic Research Service.

It's called rice mainly because of appearance, according to Barbara Stucker, an agency rice analyst. The brownish seed resembles a kernel of long- grain rice.

Also, like long-grain rice, wild rice is the seed of an aquatic grass and grows in shallow water similar to the irrigated paddies of long-grain rice, she says.

The wild rice report is in the current issue of Farmline, a monthly magazine published by the USDA agency. It said wild rice has become big business.

''Until about 20 years ago, most wild rice grew naturally in the lakes and slow-moving streams of northern Minnesota and bordering Canada,'' the report said. ''The crop was harvested by native Americans - members of the Ojibway Indian tribe - who processed it using traditional methods passed down from their ancestors.''

The Indians usually sold or traded the wild rice locally, although a small part of the crop always ended up on the gourmet market.

Today, boxes of wild rice and mixtures of wild and long-grain rice are common on supermarket shelves. And their is hope the market can develop further, according to Reynold Dahl, a professor of agricultural economics at the University of Minnesota, St. Paul.

Dahl says that U.S. cultivation of wild rice began in Minnesota in 1967 and in California as recently as 1976. The two states account for all U.S. commercial production. As far as world output, Canada is the only other producer.

In 1965, the report said, total U.S. production of wild rice was 435,000 pounds and Canada's 12,000 pounds. Last year, U.S. production was 5.55 million pounds and Canadian output 840,000 pounds.

Dahl said that wild rice cultivation was helped along by the interest of Uncle Ben's Inc., a leading long-grain rice processor, which had developed a packaged mixture of wild rice, long-grain rice and herbs.

The company would go along with national marketing only with a dependable supply of wild rice, he said. As a result, Uncle Ben's began contracting with three Minnesota farmers to plant acreages of new varieties developed by the university. From 900 acres, the state's crop has grown to more than 25,000 acres. And that doesn't count production from Minnesota's lakes and streams.

Ms. Stucker said the blends are popular because wild rice along has a nutty flavor that is considered rather strong by some people. Also wild rice prices are high and can vary greatly, from a low of about $4 per pound in Minnesota to $7 to $20 in other parts of the country.

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WASHINGTON (AP) - Farmland prices in Japan last year showed the smallest gain since the mid-1960s, says a report by the Japan International Agricultural Council.

Even so, Japanese farmland prices ''remained on a high plateau'' of about $17,000 per acre, the report said.

Japan has only about 13.3 million acres of farmland.

By comparison, U.S. farmland totals more than one billion acres and in 1984 declined in price for the third consecutive year to an average of $739 per acre nationally.

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WASHINGTON (AP) - U.S. exports of agricultural products in the first five months of the fiscal year that began last Oct. 1 are running well behind year- earlier shipments, according to Agriculture Department analysts.

The department's Foreign Agricultural Service said Tuesday that through February the value of shipments was $16.1 billion, down 6 percent from $17.1 billion during the same five months a year earlier.

''Commodity groups primarily contributing to this $1 billion decline include grain and feed, and oilseed and (oilseed) products,'' the report said. ''Less pronounced declines were experienced by the dairy, and sugar and tropical products sectors.''

Most of the value drop was due to lower prices for wheat, rice, corn, feed, soybeans and soybean meal. However, the actual quantity of some products also declined, including wheat, wheat flour, barley, soybean meal, non-fat dry milk, fresh fruit and fresh vegetables.

''Overseas markets for U.S. agricultural products continue to show weakness due to the dramatic appreciation since last fall in the value of the U.S. dollar, generally abundant carryover stocks for several major commodities and the good 1984-85 crop year for most products,'' the report said.

Department officials have projected this fiscal year's farm exports at $34.5 billion, a drop of 9 percent from $38 billion shipped in 1983-84.