During harvest, a farmer's work begin begins to pay off. The work must be done quickly, though, because the faster and more efficient the harvest, the greater the yield.
Before harvesting became a mechanized proposition, it was labor-intensive. Farmers cut crops with scythes and manually removed the seeds before bundling the stalks. Even the steam-powered threshing machine, used to separate grains from plants, required many hands.
By 1886, the first self-propelled combine had been patented and could harvest 100 acres (40 hectares) a day -- a task that would normally take days [source: ASABE].
This first combine has a lot in common with today's technologically advanced behemoths that stand nearly two stories tall. Modern combines still have a wide header attached to the front. The header has blades that cut the stalks and feed them into a threshing mechanism that removes the grain from the straw and debris. Then, a fan separates the grain and augers it to a holding bin atop the combine.
In addition to these basic functions, contemporary combines have interchangeable heads to harvest crops ranging from wheat and corn to soybeans and rice. They also have a host of technological helpers, including sensors that track the amount of grain slipping through the threshing mechanism and GPS technology to record performance data [source: Ganzel].