FACTBOX: Red River Valley braces for floods

(Reuters) - Flooding in the upper reaches of the United States bordering Canada could affect the seeding of spring wheat in as many as 500,000 acresacross North Dakota, South Dakota, Minnesota and Montana.

The Red River may crest at a record 41 feet on Saturday in Fargo, North Dakota, while flooding along the 550-mile (885-km) long river may affect the seeding of the wheat crop in up to 500,000 acres across four states.

The Red River flows north from southeast North Dakota into Canada's Lake Winnipeg, forming the border between North Dakota and Minnesota.

The river is located in an ancient lakebed and because it flows north, it is especially prone to flooding. The water freezes as it moves north into Canada. Its banks are not very high and flood waters can spread out huge distances over the flat landscape.

The Red River Valley area is known for its rich, fertile soil. Its prime farmland produces corn, soybeans, spring wheat, potatoes, and more than half of the sugar beets grown in the United States.

Here are some key facts about the Red River Valley, based on latest data from the U.S. Agriculture Department and U.S. Census Bureau.

MAJOR CITIES AND TOWNS

* Fargo, North Dakota: population 90,056

* Moorhead, Minnesota: 32,786;

* Grand Forks, North Dakota: 50,372

* East Grand Forks, Minnesota: 7,740

* Wahpeton, North Dakota: 8,443

* Breckenridge, Minnesota: 3,559

CROPS GROWN IN THE RED RIVER VALLEY REGION

SPRING WHEAT, used for bread flour and prized for its high protein content.

* North Dakota is the top U.S. spring wheat producer with 246.4 million bushels harvested in 2008, about 45 percent of the 546.7 million bushel U.S. crop. The eastern third of the state accounted for about half of North Dakota's crop in 2008.