On a late August day in 1929, a man named Lyster Dewey posed for a photograph next to a row of 13-foot cannabis plants, also known as hemp, that towered above his head. Even in the summer heat, Dewey was dressed in a long-sleeved shirt and tie, providing some evidence that his interest in the crops was not recreational.
As a longtime botanist with the U.S. Department of Agriculture, Dewey oversaw hemp production at Arlington’s Experimental Farm, a research facility that once existed where the Pentagon’s south parking lot now sits. There, under the direction of the Bureau of Plant Industry, scientists researched and grew different species, including several kinds of flowers, fruits, vegetables and other plants.
The farm was viewed as a continuation of governmental agricultural studies that dated back to the nation’s founding. At the end of the Civil War, a 40-acre federal experimental garden had been created in downtown D.C. near the National Mall, but this soon proved inadequate. Setting its sights on the Virginia side of the Potomac, Congress in 1900 approved the transfer of 400 acres from the former Custis-Lee estate, then governed by the War Department, for use as an experimental farm, along with an initial $10,000 appropriation.
At the farm, workers also tested various tools and machinery, including a “shaking machine” and a “stirring machine” that were used for making fertilizer. Other experiments involved the study of plant diseases, food dyes, road-building materials and proper crop storage.
But for decades, hemp was a major focus. Lyster Dewey conducted numerous experiments and gathered data about hemp’s suitability in fiber production, which he recorded on more than a thousand index cards—a collection that became known as the “Dewey Index”—and published in reports and articles.
Dewey was also a prolific diarist whose entries were terse but informative. “Thursday, October 19, 1922. Fair, cool,” began one entry. “Go to Arlington Farm on the 9 a.m. bus and work all day. Harvesting Kymington, Yarrow, Tochigi, Tochimington, Keijo and Chinamington hemp.”
In 1940, to make room for the construction of the Pentagon, the farm moved again—this time to Beltsville, Maryland, to become part of what is now called the Henry A. Wallace Beltsville Agricultural Research Center, which conducts research on animal health, crop production, food safety and other areas of study. (It includes the National Agricultural Library, where Dewey’s index cards are archived.) The Pentagon was completed three years later.