Chronological history by decade from
History of Research at the U.S. Department of Agriculture and Agricultural Research Service
Blue=USDA research accomplishment
Click on "more" to view related stories
Holsteins are known for producing large quantities of milk.
Hybush blueberries were initially selected from wild strains.
USDA made initial crosses between Lincoln and Ramboullet sheep breeds, leading to the Columbia breed.
The roots of soybean and alfalfa plants help keep soils healthy and fertile, thanks to the Rhizobium bacteria that live in them.
Demonstrated that pasteurization kills toxin-producing organisms in raw milk without destroying beneficial lactic acid bacteria.
Insecticide and Fungicide Act passed.
Brucella abortus first isolated from cattle in the U.S.
Of gainfully employed persons, 31 percent were engaged in agriculture.
Demonstrated that typhus fever is transmitted by lice.
Cossack alfalfa released.
Discovered a virus that can cause cancer in chickens; first experimental proof of an infectious agent of cancer.
Rubel highbush blueberry selected in the wild.
Radioisotope labeling invented.
Seed Importation Act prohibited entry into the U.S. of certain adulterated grains and seeds unfit for seeding purposes.
Federal Plant Quarantine Act passed.
Thomas Hunt Morgan announced his theory of genes; began using the term 'gene in 1904 to describe individual parts of chromosomes that control particular characteristics. (more)
USDA makes initial crosses between Lincoln and Ramboullet sheep breeds, leading to the Columbia breed.
Demonstrated that drought begins when soil moisture is so diminished that vegetation is unable to absorb water from the soil rapidly enough to replace the water lost to the air by transpiration.
Forerunner of the light tractor introduced.
Rhizobium nodules from soybean plants started world's first rhizobium collection; established as a formal collection in 1975.(more)
First U.S. veterinary license issued for production of anti-hog-cholera serum. (more)
Smith-Lever Act formalized cooperative agricultural extension work.
Cultures of nitrogen-fixing bacteria supplied to legume growers for the purpose of increasing the plants' nitrogen-fixing capacity.
Two publications reporting research on terraces and control of gullies printed. They remain the standard reference works in their field for erosion control. (more)
Studies made of precooling to prevent decay in red raspberries; these studies led to precooling as an established agricultural practice.
Calcium arsenate developed for use on boll weevil.
United States Grain Standards Act passed.
Federal Farm Loan Act passed.
Standard Container Act passed.
Federal Highway Act provided for cooperation with states in construction of rural post roads.
Japanese beetles discovered in New Jersey.(more)
European corn borer discovered near Boston, MA.
United States entered World War I.
U.S. grade standards for potatoes issued, representing the first official grade standard for a fruit or vegetable issued by USDA.
Pink bollworm discovered in Texas.
Demonstrated that raw milk could transmit a bacterium, Brucella abortus, that causes brucellosis in cattle and undulant fever in humans.
Long-term study of dairy improvement started; increased production per cow from 542 pounds of butterfat in 1920 to more than 720 pounds today.
World War I ended.
Discovered that relative day and night length control flowering, known as photoperiodism.(more)
Discovered existence of pathogenic races of plant fungi.
Discovered temperature necessary to kill trichinae.
Send comments or questions about this historical timeline to Sean Adams.