Plowing is the most difficult part of farming. It is accomplished by using a tool to dig deep into the earth to prepare it for planting. The trench must be deep enough for embedding the seeds. The first tool used by people when the art of farming was discovered as a means to continuously produce food was a spade. At that time, it was made of stone fitted onto a small wooden handle. Farmers then used the spade to manually dig trenches. Obviously, using that type of tool made plowing extremely time consuming and difficult. Over the centuries, advancements in technology resulted in more efficient plowing tools that allowed farmers to plow land faster and with less effort.
In ancient Egypt, farmers used a variation of the simple spade for plowing. They used a long stick with a stone edge at the bottom called a hoe. The hoe was then put to work using the strength of the farmer, plunging the stone edge deep into the earth and then dragging it along as he moved forward along a straight line.
Later on, the scratch plow was invented which was a simple hoe fashioned over a curved wooden frame. The two sides of the frame were then roped around a domesticated animal such as an ox. The ox would then be driven to move forward, dragging the makeshift plow across the field. Today, this design is still being used in many third world countries, but has been reconstructed and redesigned to fit a large and sharp metal blade at the bottom. It is known as a basic moldboard plow. Variations to this design were made over the next centuries using more mechanical means and a larger frame that allowed for more blades to be fitted. These variations allowed for multiple and deeper trenches to be plowed simultaneously in a single run.
Machinery has become the primary equipment for plowing. These automotive plowing machines replaced animals as the driving force for the plow. And, with it, the design of the plow changed. When tractors were first used to plow fields, the moldboard design was fitted with multiple blades for plowing multiple trenches in a given field. Furthermore, new designs of plows such as the reversible and the sub-soiling plows started springing up. The reversible plow is fitted with a set of two to six blades rotating to sift and dig soil alternately side to side. The sub soiling plow, on the other hand, features a heavy plow design specifically for deeper plowing, way beneath the top layer of the soil.
Today, there are a variety of modern plow designs to choose from. Each design is specifically constructed for a particular application. For instance, a moldboard or reversible plow is used for traditional farming, where the soil does not need to be deeply disturbed. Sub-soiling plows as well as disc plows, where round, concaved steel discs are used, are typically utilized for plowing hard and rocky soil.