|  | The U.S. National Arboretum is established in 1927 at New York Avenue and Bladensburg Road in Washington, DC. |
 |  | Landmark studies are conducted, comparing the anatomy, skeletal structure, mammary gland and blood circulatory system of highly specialized dairy and beef cows. Both types are found to be very similar despite wide variations in external appearance.
The meat-type hog is developed, leading to today's leaner animal. At the same time, a system of producing pork with a minimum of feed and labor is also developed. |
|  | High-laying strains of Rhode Island Red and Single-Comb White Leghorn chickens, which lay especially large and well shaped eggs, are developed. Researchers also determine the precise amount of feed needed to produce one dozen eggs, giving farmers better control of production costs. |
|  | The Bureau of Home Economics is established in 1923 under the Division of Food and Nutrition. Various surveys are conducted to compare rural and urban living. |
|  | Additional land is acquired around the Walnut Grange plantation for dairy and animal husbandry research. By 1926, the original 475 acres is expanded to 1662 acres. By 1929, animal husbandry included 60 permanent buildings (offices, laboratories, residences, barns, storage buildings, garages, a mill, and work shops) and 160 small animal and poultry houses. |
|  | `Mary Wallace', the first shrub rose that is also multi-disease resistant, is released. This rose is named after the daughter of the Secretary of Agriculture, Henry Wallace In 1928, this rose is voted the most popular rose in the US. |
