USDA Research Helps Preserve Historic Flag

By Jim Core
July 3, 2001

As the nation prepares to celebrate its 225th birthday tomorrow, Agricultural Research Service wool experts can take pride in knowing they helped the Smithsonian Institution gain additional insight into a national treasure, the flag that inspired the “Star-Spangled Banner.”

The flag’s fiber and dyes have degraded over the years, despite care by its custodians. Exposure to light, temperature fluctuations and humidity have sped deterioration of the 150-pound wool flag, its cotton stars and its linen support over its lifetime.

Scientists William N. Marmer, Jeanette M. Cardamone and colleagues at USDA’s Agricultural Research Service in Wyndmoor, Pa., worked with the Star-Spangled Banner Preservation Project to assess the flag’s deterioration using high-tech equipment at the Wyndmoor lab. They collaborated with the project’s chief conservator, Suzanne Thomassen-Krauss, of the Smithsonian’s National Museum of American History.

The researchers, based in the ARS Eastern Regional Research Center’s Hides, Lipids and Wool Research Unit, offer unique expertise in this area. They are the only federal researchers working on the utilization of domestic wool. The unit is responsible for developing and patenting new technology for bleaching and dyeing wool, as well as technology to monitor those processes.

Cardamone’s team examined the fabric structure for signs of damage utilizing images taken by the Smithsonian. The scientists used Digital Image Analysis for Fabric Assessment (DIAFA) to analyze authentic flags from the same era, as well as a new flag Cardamone wove to simulate the original. From the digital images, they developed a mathematical procedure to determine yarn spacing and thickness without risk of damage to the delicate areas of the actual flag.

Cardamone says their methods are designed to give characterizations of the flag’s fabric and are less tedious than traditional techniques. ERRC scientists can now present findings based on their methods to the Smithsonian’s textile conservators, who may apply the technique to the Star-Spangled Banner when deciding how to monitor its condition over time.

The 30- by 34-foot flag has been in the Smithsonian’s collection since 1907. The National Museum of American History built a special conservation laboratory to accommodate the flag, which was moved there in 1999 as part of the three-year conservation project to better care for, exhibit and store it.

ARS is the U.S. Department of Agriculture’s chief scientific research agency.