Wisconsin dairy industry

Dairy is a major industry in the state of Wisconsin. The state is widely known for its dairy production, as can be seen with "America's Dairyland" being one of Wisconsin's nicknames. 
Dairying in Wisconsin includes the harvesting and processing of animal milk, usually from cows, and the processing into cheese, butter, or other dairy products. Dairy became an important industry in the late-19th century, following the invention of the refrigerated rail car. By 1915, Wisconsin became the leading state for dairy production, only being surpassed by California in 1993. As of 2018, Wisconsin ranks 2nd in the United States in dairy production, with over 7000 dairy farms that produce of milk per month.
Farming.
Traditionally, dairy farming in Wisconsin involves family-owned farms. Dairy cows, in a herd of over 100, are usually kept in a pasture and milked in the barn, two or three times per day. Factory-farms, which are able to have significantly more cows, are becoming increasingly more common in Wisconsin, forcing smaller family farms out of business.
Cheese.
Cheesemaking has been in Wisconsin since the start of its dairy industry. In the 19th century, much of the milk production went to making cheese, because cheese kept longer than milk or butter. In the latter half of the 19th century, cheese production moved from the farms to specialized factories, resulting in higher quality cheese. In 1921, Wisconsin became the first state to grade cheese by its quality. As of 2020, Wisconsin produces 26% of all cheese in the US, totaling of cheese in the last year.
Butter.
Butter is another common dairy product produced in Wisconsin. The state requires buttermakers to hold a license to produce butter. These rules were created in 1929, in order to prevent substandard product from being sold as Wisconsin butter. As of 2008, Wisconsin produces 22% of butter in the US, totaling of butter.
History.
The Wisconsin dairy industry has its start in the latter half of the 19th century. The first farms in Wisconsin exclusively produced wheat. At their peak, Wisconsin farms produced of wheat. Rapidly, in the 1860s, the wheat farms, began suffering mass soil depletion, and insect infestations, lowering the quality and yield of the crop. During the 1880s, with pressure from the Wisconsin Dairymen’s Association, farms across the state began switching to producing dairy.
With the invention and widespread use of the refrigerated rail car, this allowed many farms to switch to producing dairy products and raising feed crops instead of wheat. This turned out to be highly successful for these farmers, and by the start of the 20th century, over 90% of farms were involved with the dairy industry. 
In 1890, Stephen Babcock from the University of Wisconsin–Madison developed a test to determine the milkfat content. This innovation led to a higher quality of milk and dairy products. By 1915, Wisconsin became the leading state for dairy production, a lead it would maintain until 1993.
In 1895, the Wisconsin legislature prohibited the sale of yellow-colored oleomargarine, fearing that it would disrupt the state's dairy industry. Manufacturers switched to producing pink-colored margarine as a response to the ban. The margarine ban lasted for 75 years, when it was overturned in 1967. Wisconsin was the last state to maintain its oleomargarine ban, the previous being Minnesota, which overturned theirs in 1963. It, however, still remains illegal for restaurants to serve margarine, unless the customer requests for it. While the ban was never enforced, it carried a $6,000 fine. 
In 1933, during the Great Depression, there was a series of strikes by Wisconsin dairy farmers in attempt to raise the price of milk. The cooperative group of farmers attempted to coordinate their efforts with larger groups, including the Farmers' Holiday Association. However, the larger groups prematurely ended their strike to avoid losses.
When states, such as California, started to experiment with new factory-farms, they saw great success, compared to Wisconsin's family farms. Throughout the late 20th-century, California dairy production started to grow rapidly, replacing Wisconsin as the leading state for milk production in 1993. Many of Wisconsin's family farms have been closing down, due to increased competition from large factory farms. Since 2005, about 50% of the dairy farms have closed, leaving Wisconsin with 7000 dairy farms in 2020.
Rising tariffs on dairy products have also been a major contributor to the decrease in productivity in Wisconsin. In 2018, China and Mexico imposed large tariffs on the US, making it harder for farms to sell their dairy products. Farmers across Wisconsin lost an estimated $40,000 in yearly revenue due to these tariffs. The number of immigrant dairy workers is rising, from 5% in 2000 to 40% in 2010. This increase is due to many farmers looking to increase the size of their herds, which requires more workers.
The COVID-19 pandemic has been another hardship on the Wisconsin dairy industry. As the demand for dairy fell, Wisconsin farmers were forced to dump their excess milk. With the loosening of state lockdowns, dairy demand had increased to near pre-pandemic levels. By November 2020, most farms had rebounded from the initial COVID-19 lockdowns.
Cultural significance.
The prominence of the dairy industry in Wisconsin has led to Wisconsin being known as "America's Dairyland". In the 1940s, "America's Dairyland" was printed on the state's license plates, and in 1986 a graphic representing a dairy farm was added to the plate. In 1971, the dairy cow was designated as the official state domesticated animal. "Cheeseheads" is used as a nickname for people from Wisconsin or fans of the Green Bay Packers NFL football franchise. Cheese-wedge shaped hats are a common sight at Packers games, especially since 1994.