During the many years that Dr. Moore was Director, the Garden would face a series of unexpected problems, including the problem of air pollution from the burning of coal in the city, the World Wars and the Depression.
The growth of the city of St. Louis created certain problems for the Garden. The primary form of heat for the city was the burning of coal, both for industrial and home use. On a cold winter day, one warmed oneís home by burning coal in the furnace. The problem was that the coal did not burn cleanly and so much coal was burned that huge black clouds formed over the city, especially in winter when natural weather patterns kept the smoke trapped over the city. In the 1920s, there were several incidents in which large clouds of smoke hung over the city for days at a time. During one such incident in 1925, it was estimated that each person in St. Louis inhaled 15 tablespoons of soot over the five-day period. The Garden was active in publicizing this problem and working toward a solution. The Garden purchased a machine that measured the amount of pollutants in the air as it filtered the air for the green houses. George Moore was active in promoting smoke abatement projects and in seeking solutions to the problem of the deadly clouds of smoke.
The Garden was so active in fighting the smoke pollution in part because the large clouds of smoke were killing the Gardenís plants. The Garden had become one of the leaders in the world in collecting and studying the orchid family, and over time the garden had amassed a large and extremely expensive collection of orchids. These delicate plants were especially vulnerable to the smoke, even though they were grown in the green houses.