The United States
The U.S. population was approximately 310 million in 2010. The country is highly industrialized. The populace is employed principally in manufacturing and service industries, with only 1.5% directly involved in agriculture. Agriculture represents only 1.2% of the gross domestic product.
U.S. rice production in 2010 was 11 million t, accounting for about 1.6% of total world production. The rice was grown on 1.46 million ha, with an average yield of 7.5 t/ha. Rice is grown in seven states, but three states—Arkansas, California, and Louisiana—together accounted for about 82% of U.S. rice area and production. Long-, medium-, and short-grain types are grown throughout the U.S. rice areas; however, the southern states grow predominately long-grain types whereas California grows mostly medium-grain types. Most rice farms in the southern states are now planted to hybrid rice whereas California varieties remain mostly conventionally bred varieties.
Arkansas is the main U.S. rice-growing state, producing about 42% of U.S. production. Arkansas harvested 3.6 million t on 467,000 ha in 2011. California was second, harvesting 2.2 million t on 234,000 ha; followed by Louisiana, 1.2 million t on 169,000 ha; Mississippi, 0.5 million t on 64,000 ha; Texas, 0.59 million t on 73,000 ha; and Missouri, 0.38 million t on 52,000 ha. Florida and some other states also grow small amounts of rice.
The U.S. exported about 3.8 million t of rice, mostly milled, in 2010. That is about 12% of all world exports, making the United States the fourth-largest exporter of rice (after Thailand, Vietnam, and China). The main markets for U.S. rice are Canada, Haiti, Japan, Mexico, Saudi Arabia, and Turkey.
Although low compared with most Asian countries, annual per capita U.S. rice consumption more than doubled from 1980 to an all-time high of 12.3 kg per person in 2000, but fell to 8.3 kg by 2009. Direct food use accounts for 63% of U.S. consumption; processed foods, including pet food and baby food, 22%; and beer, 15%. Part of the increase in direct food use is because of marked increases in Asian and Hispanic populations, who prefer rice, which has broadened the general interest in rice as a food. Imported rice constitutes 18% of direct food consumption; most is aromatic Thai jasmine and Indian and Pakistani basmatis, consumed by ethnic Asians and increasingly appreciated by the general American population. Arborios are also imported from Italy.
The brewing company Anheuser-Busch is the largest purchaser of U.S. rice, buying about 8% of the annual crop. The brewing giant owns its own rice mills in Arkansas and California. Budweiser, its most popular beer brand, uses rice as an adjunct. Rice and corn flour are used in other Anheuser-Busch beers. Coors is also a rice-based beer.
In Asia, weedy and wild types of rice are often referred to as wild rice. However, American “wild rice,” favored by gourmets, is not rice at all; it is Zizania palustris, a semiaquatic cousin to rice and a grass native to the Great Lakes region of the U.S. and Canada. Native North Americans have gathered and eaten wild rice for thousands of years. It is still harvested wild, although domestication in Minnesota began in the 1950s—perhaps the first cereal to be domesticated by humans since the time of the pharaohs. It is still comparatively wild with regard to plant variability and seed shattering. Wild rice is grown commercially in Minnesota, California, and Canada. In the U.S., wild rice is now grown in much the same way as “real” rice, in flooded fields, with yields of up to 1.6 t/ha in Minnesota and twice that amount in California. In Canada, commercial production is mainly from leased lakes that are seeded; the leaseholder is given exclusive harvesting rights and much of the harvesting is done using airboats. Wild rice is a recalcitrant seed and thus cannot be dried for storage. In Minnesota and Canada, shattering onto wet soils provides the seed for next year’s crop. In California, wild rice planting seed must be kept in bins saturated with water and placed in cold storage over winter.
Rice production data show that rice in the U.S. is grown in three principal areas: the Grand Prairie and Mississippi River Delta of Arkansas, Louisiana, Mississippi, and Missouri from 32° to 36°N; the Gulf Coast of Florida, Louisiana, and Texas from 27° to 31°N; and the Sacramento Valley of California from 38° to 40°N. The climate varies from semiarid California, with less than 50 mm of rainfall during the growing season, to the humid subtropical Gulf Coast of Louisiana, Texas, and Florida, where rainfall may total 700–1,000 mm. In all these environments, rice is grown as a single crop per year, but can be ratooned in the warmest, southernmost regions of the Gulf Coast states. Approximately 40% of Texas and southwestern Louisiana rice area is ratooned annually. All rice in the U.S. is irrigated and direct-seeded. In California, pregerminated seed is sown into standing water by aircraft. Southwestern Louisiana is also wet-seeded. Dry seeding with a mechanized grain drill is the most common method of planting in the southern U.S.
Rice is grown on natural flatlands. Nearly 100% of these flatlands in California and much of the southern U.S. have been further leveled by laser-directed machinery.
In rice monocrop systems, the land may be leveled to a slope of 0.02 to 0.05 m/100 m. In rice–row crop systems, grades of 0.1 to 0.2 m/100 m are required for drainage or irrigation of the rotation crop. Precision leveling has greatly facilitated water management and is considered second only to the introduction of semidwarf varieties as contributing to increased rice yields.
In California, where the rain-free environment and high latitude provide maximum solar radiation and low disease pressure, farm yields average 8–9 t/ha. In the humid southern rice environments, disease (primarily blast and sheath blight), warm nights, cloudy days, and frequent thunderstorms at heading limit average yields to about 6.5 t/ha.
Problems and opportunities
Although U.S. yields are high, several problems constrain production:
- In the humid subtropical climates of the Gulf Coast and Mississippi River Delta areas, diseases (particularly blast and sheath blight) limit yields.
- Because all areas are direct-seeded, weeds and poor stand establishment are significant problems. The number of weeds resistant to herbicides has greatly increased in the last 20 years, making weed control the number-one production problem for most farmers.
- In the southern U.S., many share-crop arrangements are short term and tenant farmers are reluctant to spend capital for long-term improvements to productivity.
- An indirect production constraint is embodied in concern about agriculture’s role in environmental degradation. All U.S. agriculture now operates within a stringent and costly regulatory environment. One critical concern is maintaining high-quality surface water and groundwater with respect to potable water, the health of aquatic organisms, and recreational uses.
- In some areas, especially California, degradation of air quality from burning rice straw is highly regulated and rice straw disposal is a production problem.
- Concerns are increasing about the impact of rice production on global warming and climate change through methane and nitrous oxide emissions and the potential regulatory impact.
Rice research and extension are an integral part of the U.S. Department of Agriculture and University Land Grant system, supplemented by private research and development, primarily by commercial seed and agricultural chemical producers. All of the principal rice-growing states have well-staffed and -equipped public-sector rice research stations. Scientific exchange among these institutions is linked by the U.S. Rice Technical Working Group. Linkages to IRRI and other international programs on rice are scientist-to-scientist, mostly on an ad hoc basis.
The challenges for U.S. rice production are to maintain high yields and quality as well as the sustainability of the rice-based cropping system, in the context of maintaining and improving soil, air, and water quality in an increasingly regulated environment. Improved technology and equipment for land and irrigation management and for harvesting and handling high-quality rice; varietal improvement through the integration of genetic engineering and conventional breeding programs; integrated pest and crop management; and the development of sophisticated pest control technology will be key elements in future production opportunities.
Maize is the main staple of the 114.8 million (2011) inhabitants of Mexico, but the country currently produces more than 200,000 t of rice annually. Rice is grown in at least 17 states, the three major states being Sinaloa, Campeche, and Veracruz, each of which contributes slightly more than 20% of the nation’s total rice production. Other states producing significant amounts of rice (2% to 6%) are Tabasco, Colima, Tamaulipas, Morelos, Nayarit, Michoacán, and Jalisco.
Production varied during 1980-2000 with little discernible trend. Since then, production has been gradually declining, from 351,000 t in 1980 to 217,000 t in 2010. During 1980-2000, the harvested area decreased from 127,000 ha to 84,000 ha, indicating gradual yield improvement in that period. Subsequently, the harvested area fell by about 40%, as did the harvest, suggesting little further yield gains in recent years.
Annual per capita consumption of rice fell from around 8 kg in 2000 to about 6 kg in 2009. Nevertheless, consumption is not sustained by domestic production. Imports of rice grew from less than 100,000 t in 1980 to more than 400,000 t in 2000, and have continued to increase, to 572,000 t in 2010. Most is imported from the U.S. for which Mexico is the largest export market.