Rice Production in the World and in the U.S.
Rice is different from all other crops in that it is usually grown in a flooded field. The base of the rice stalk will be under water most of the growing season. Rice can be grown on dry ground and is sometimes grown in that manner in developing countries, but the field yields are much lower and quality is lower with dry land rice. Rice is essentially a type of grass. It is an annual and happens to grow well in water. When grown on dry land other grasses and weeds can overtake rice and dramatically reduce field yields and quality. (There are no herbicides that can selectively kill other grasses without killing rice.) Controlled flooding of rice fields is a very effective means of weed control and rice flourishes in water. In areas with short growing seasons, the rice only yields one crop. In some areas after cutting, the rice is allowed to grow back and produce a second crop. Rice typically needs about 120 days of warm sunny weather to grow and mature, rice needs soil that can hold water. (Imagine trying to grow rice on sandy land.), and there must be an abundance of water to economically grow the crop. For mechanized farming, the land must be able to be drained and hold heavy equipment. These factors limit the acreage where rice can be grown.
Most rice is still grown the old fashion way, by hand. The seeds are germinated and the seedlings carefully grown until they reach a certain level of maturity. They are then transplanted by hand into flooded fields. They are usually planted in rows with space between the plants. They are put in the flooded soil one at a time. Weeds are pulled by hand until the rice has grown too thick for labors to walk through the field. Fertilizers are spread by hand.
Sometime before harvest, the water is pulled from the field and the ground is allowed to dry. The rice ready for harvest is often cut by hand. In some countries, the straw with the rice attached is stacked in a special manner to dry. In other countries, the rice is threshed and spread on the ground, pavement, or highway to dry. It is surprising to see in some advanced countries like Japan, most of the work is still done by hand. There are small machines to facilitate the planting of the seedlings. A mechanical harvester cuts most of the rice in Japan, but the harvester is only a few feet wide. The rice is still dried in the field.
Rice is one of the most beautiful crops in the world. The level of the water is critical to the well being of the plant. Ideally, there should not be more than a two-inch variance in the depth of the water within a field. For this reason, you see the beautiful curving lines of levees around the fields of rice. Winding terraced fields are formed in the following manner: Start at the highest point of the field and then go out as far as possible without dropping more than two inches in elevation and make a levee. If the land is not flat, then the levee will not form a perfect circle or square. It will take its own unique winding shape. From that first levee, go out as far as possible and make another levee without dropping more than 2 inches in elevation. Continue in this manner throughout the field. Pump water into the field of highest elevation and then allow the water to flow over a level control gate into the next field and then the next. The result is a very strange and beautiful pattern of fields surrounded by winding levees.
Rice farming in the U.S. is the most advanced in the world. Rice fields are leveled with lazers and shaped into large square fields with less than a one inch difference in elevation. (A laser beacon is placed in the center of a field and set to send a perfectly level signal all across the field. A land leveler is set to receive the signal and adjust its blade to a precise elevation to level the ground.) In the spring, the large tractors with disks (exceeding 20 feet in width) till the soil to kill weeds and prepare a seedbed. The soil is leveled and fertilized. Some farmers roll small groves into the soil to give the seeds a location to settle during planting. Rice seeds are put in water for a couple of days to allow germination prior to planting. The seeds are then put in agricultural airplanes where they are dropped from the sky into the flooded fields. The airplanes use satellite guidance systems to mark their locations and assure perfect overlap on the seeding.
The water level is then carefully raised over time to follow up the growing plant and prevent any weeds from growing in the rice. Any fertilizers, herbicides, or pesticides are applied by airplane. Several weeks prior to harvest, the water is pulled off and the land is allowed to dry. Large combines with cutter bars over 20 feet wide enter the field and cut the rice and thresh the rice. The straw is mulched and spread back onto the field. The rice is put in trucks and carried off to commercial dryers where it is dried in large column dryers and then placed in the paddy form into storage bins.
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