Longhorn Army Ammunition Plant

The plant ran far longer than the war it was built for. The Handbook of Texas says Monsanto picked the 8,500-acre site beside Caddo Lake in December 1941 and that the $22.5 million works began operating on October 18, 1942. It closed in November 1945, sat on standby until February 1, 1952, and reopened under Universal Match until 1956. Thiokol built its rocket motor facility between 1953 and 1955, and motor production continued until early 1971. In 1989 the plant was chosen to destroy Pershing missiles under the Intermediate Nuclear Forces Treaty, a job finished in 1991.

What the plaque says

Longhorn Army Ammunition Plant In 1941, as the United States prepared for eventual entry into World War II, the U.S. Army Ordnance Department approached Monsanto Chemical Company of St. Louis about operating a local plant for production of explosives. Initially called Longhorn Ordnance Works, the plant produced over 400 million pounds of trinitrotolulene (TNT) from 1941 to 1945. After the war, the Army placed the plant on standby status. During the Korean War (1950-1953), the need for munitions rose again, and the Universal Match Corporation, also of St. Louis, managed the site, producing propellant fuel.In 1956, Thiokol Chemical Corporation began manufacturing solid fuel rocket motors here. This highly guarded and classified site grew in a series of five expansions. In 1964, its name changed to the Longhorn Army Ammunition Plant and employment rose to a high of nearly 3,000 personnel. The numbers declined with the end of the Vietnam War and the easing of tensions with the Soviet Union, and employment dropped to less than 1,000 by 1975.In 1987, the United States and the Soviet Union signed the Treaty of Intermediate Nuclear Forces, beginning the elimination of an entire class of missiles. In 1988, the first destruction on American soil of U.S. Pershing I and II rocket motors occurred at the site. Observed by Soviet and U.S. officials, the demolition project continued until 1991. Following official deactiviation in 1995, pollution abatement has steadily provided for adaptive reuse of the former wartime site, now part of the Caddo Lake National Wildlife Refuge. (2007)

Where it stands

Worth the stop nearby

• Caddo Lake National Wildlife Refuge — steps away
  Wetlands and woods on part of a former ammunition plant, now a refuge for wood ducks, prothonotary warblers and alligator snapping turtles, with four easy trails and a free visitor center on a Ramsar lake.
• Caddo Lake State Park — 1.0 mi
  A Civilian Conservation Corps park on the Texas shore of Caddo Lake, where the Caddo told of a lake made by wind-driven water and visitors now paddle Big Cypress Bayou past moss-hung bald cypress.
• Excelsior House Hotel — 12 mi
  A brick-and-timber hotel at 211 West Austin that began as a river captain's boarding house in 1858 and was revived by a garden club in 1959, and still takes guests with rosewood furniture.
• Jefferson Historical Museum — 12 mi
  A four-floor museum in Jefferson's 1888-90 federal post office and courthouse, with rooms for African-American history, Jewish heritage, the Caddo and Diamond Bessie, bought by the historical society in 1965 for $8,100.

More markers nearby

• Hometown of Mrs. Lyndon B. Johnson — steps away
• Old Town of Port Caddo — 1.0 mi
• Leigh Community Center and Health Unit — 1.4 mi
• Marshall-Shreveport Stagecoach Road — 7.7 mi