In British English such material is more usually known as turf, and the word "sod" is limited mainly to agricultural senses (for example for turf when ploughed).
Sod is typically used for lawns, golf courses, and sports stadiums around the world. In residential construction, it is sold to landscapers, home builders or home owners who use it to establish a lawn quickly and avoid soil erosion. Sod can be used to repair a small area of lawn, golf course, or athletic field that has died. Sod is also effective in increasing cooling, improving air and water quality, and assisting in flood prevention by draining water.
Following passage of the Homestead Act by the US Congress in 1862, settlers in the Great Plains used sod bricks to build entire sod houses. While it might be hard for some to imagine sod as a suitable primary building material, the prairie sod of the Great Plains was so dense and difficult to cut it earned the nickname Nebraska marble. Blacksmith John Deere made his fortune when he became the first to make a plow that could reliably cut the prairie sod.
Sod is grown on specialist farms. For 2009, the United States Department of Agriculture reported 1,412 farms had 368,188 acres of sod in production.
It is usually grown locally (within 100 miles of the target market) to minimize both the cost of transport and also the risk of damage to the product. The farms that produce this grass may have many varieties of grass grown in one location to best suit the consumer's use and preference of appearance.
It is usually harvested 10 to 18 months after planting, depending on the growing climate. On the farm it undergoes fertilization, frequent watering, frequent mowing and subsequent vacuuming to remove the clippings. It is harvested using specialized equipment, precision cut to standardized sizes. Sod is typically harvested in small square slabs, rolled rectangles, or large 4-foot-wide (1.2 m) rolls.
Mississippi State University has developed a hydroponic method of cultivating sod. For the very few sod farms that export turf internationally, this soil-less sod may travel both lighter and better than does traditional sod when shipped. Additionally, since the sod is not grown in soil, it doesn't need to be washed clean of soil down to the bare roots (or sprigs), and time to export is shortened.
In many applications, such as erosion control and athletic fields, immediacy is a key factor. Seed may be blown about by the wind, eaten by birds, or fail because of drought. It takes some weeks to form a visually appealing lawn and further time before it is robust enough for use. Turf largely avoids these problems, and with proper care, newly laid sod is usually fully functional within 30 days of installation and its root system is comparable to that of a seeding lawn two or three years older. Sod reduces erosion by stabilizing the soil.
Many prized cultivars (such as Bella Bluegrass) only reproduce vegetatively, not sexually (via seed). Sod cultivation is the only means of producing additional plants. To grow these varieties for sale, turf farms use a technique called sprigging, where recently harvested sod mats are cut into slender rows and replanted in the field.
Bermudagrass is quite commonly used for golf courses and sports fields across the southern portions of the United States. It tolerates a range of climates in the US, from hot and humid in the Gulf Coast to arid in the southwest and lower Midwest. "Established bermudagrass is a network of shoots, rhizomes, stolons, and crown tissue together that usually form a dense plant canopy. This dense plant canopy can be used to propagate clonal varieties by sod, sprigs, or plugs. The aggressive and resilient nature of Bermudagrass make it not only an excellent turfgrass, but also unfortunately a challenging invasive weed in land cultivated for other purposes. Its one noted weakness is shade tolerance. Given the economic importance of Bermudagrass (as a sod product, agricultural forage and, at times, an invasive weed), it has been the subject of numerous studies.
- Celebration Bermudagrass
- "‘Celebration’ is a dark green, fine textured, aggressive, traffic-tolerant cultivar with high recuperative potential and drought tolerance." The cultivar is a breed of Cynodon dactylon from Australia developed by turfgrass breeder Rod Riley. The grass has a distinctive deep blue-green color which makes it popular on golf courses and for private home lawns throughout the southern United States. As a leading cultivar, the research on Celebration is extensive. The United States Golf Association rated Celebreation best for shade tolerance. A researcher at the University of Florida report noted this cultivar's "good wear tolerance, good quality and color ratings" in the Central Florida environment. Celebration was the overall best-performing turf grass in a 2-year drought resistance study commissioned by the San Antonio Water System and performed by Texas A & M extension serrvice. The cultivar was also the top-rated Bermudagrass for drought resistance in a test conducted in South Carolina. Along with many golf courses across the southern United States, the Tampa Bay Buccaneers elected to install Celebration bermudagrass in their stadium.
- Discovery Bermudagrass
- Discovery is a bermudagrass that has an exceptional dark blue-green color. It also has extremely slow vertical growth which means that it only needs to be mowed once a month. Discovery has the drought toughness of a bermudagrass, but does not need to be maintained as much as other varieties. It was developed in Europe. It was made available in the United States in 2011 by Sod Solutions which owns the right to market it in the United States. It grows well in all of the southern United States.
- Bella Bluegrass
- Bella Bluegrass was developed by the University of Nebraska as a drought resistant grass that would help states conserve water. It was immediately embraced by schools and homeowners in the state of Utah who are voluntarily trying to conserve water. Bella is the world’s first dwarf, vegetative Bluegrass. It is sold only as sod, not as seed. Bella is a quick grower laterally, but has very minimal vertical growth. Because it only grows to about 4" in height, it requires less mowing. It grows in sand, clay, muck and peat, and is currently being adopted across the northern United States.
St. Augustine grass
St. Augustine is warm season, perennial grass that is a widely used. A native grass of tropical origin that extends from water marshes (salty & fresh), lagoon fringes, and sandy beach ridges.
Saint Augustine lawns are a popular wide bladed (coarse) lawn planted throughout many areas of the Southeastern USA. This grass is found in Mexico, Australia, and in tropical parts of Africa. It is a warm season grass that does not handle cold weather very well. The majority of this grass is planted vegetatively (PLUGS, SOD) as seeds are not usually available commercially each season due to production difficulties.
- Captiva St. Augustine
- Developed by the University of Florida in 2007, Captiva is a chinch bug resistant St. Augustine cultivar. It has a lush, dark green color with a dense canopy and a massive root system. Because it has a slow leaf blade growth and lateral spread, the requirement for mowing is reduced. Captiva has good-excellent shade tolerance and has excellent pest resistance which means there is less need to use pesticides.
- Centipedegrass was introduced into the United States from southeastern Asia in 1916. It does well in the climate and soils of central and northern Florida and is the most common home lawn grass in the Florida Panhandle. Covington is a proprietary cultivar of centipede grass from Sod Solutions, Inc. that grows in the southeast United States, from the west half of Texas to all of Louisiana, and most of Mississippi, Alabama, Georgia, South Carolina, North Carolina and Virginia. It is the only uniformly green centipede grass on the market. It is a low maintenance grass, which retains its color in the fall and greens quickly in the spring. This variety is currently being evaluated by the University of Florida.
- Santee is another new proprietary selection from Sod Solutions, Inc., also being evaluated by the University of Florida for adaptation to Florida use.
- "Use Sod For Quick Repair Of Damaged Lawns". Louisiana State University, Agricultural Center, Research and Extension. Retrieved December 2011.
- "Why Sod is Good for the Planet". Sod Growers Council. Retrieved 14 June 2014.
- "Life in a Sod House". Smithsonian. Retrieved 17 March 2013.
- "The Tallgrass Prairie: An Endangered Landscape". CSA. Retrieved 20 March 2013.
- "Table 29. Sod, Sprigs, and Plugs Sold: 2009". Us Dept. of Agriculture. Retrieved 17 March 2013.
- "Sod Production: From an Economic Standpoint". MU Plant Sciences, University of Missouri. Retrieved 20 March 2013.
- Ratliff, Bob. "MSU-Developed Sod". Mississippi Landmarks Magazine, Volume 2 Number 4. Division of Agriculture, Forestry, and Veterinary Medicine at Mississippi State University. Retrieved 25 March 2013.
- "The High Cost of Instant Gratification; To Sod or to Seed?". Streamline Publications. Retrieved December 2011.
- "Sod vs. Seed". Central Sod Farms, Inc. Retrieved December 2011.
- Shearman; Robert C. ; et al. "US Patent Application Poa pratensis L. named 'NE-KYB-05-001'". US Patent Office. Retrieved 27 March 2013.
- "A Taxonomic Key for Selected Turf-Type Bermudagrasses". Tarleton State University. Sam Houston State University. Retrieved 19 March 2013.
- "Bermudagrass". University of Hawaii. Retrieved 19 March 2013.
- Sod Solutions announces death of turfgrass developer Rod Riley World Golf, December 5, 2008
- "Turfgrass and Environmental Research Online". USGA. Retrieved 20 March 2013.
- "Turf Grasses: The Quest for the Ideal Lawn Continues". University of Florida. Retrieved 19 March 2013.
- "Evaluation of Sixty-Day Drought Survival in San Antonio of Established Turfgrass Species and Cultivars". Texas A&M University. Retrieved 19 March 2013.
- "Response of Six Bermudagrass Cultivars to Different Irrigation Intervals". Horttechnology. Retrieved 19 March 2013.
- Citrus Bowl getting new sod retrieved January 8, 2010
- North Carolina Crop Improvement Association (NCCIA) Certified Sod
- John Hollenhorst New variety of Kentucky Bluegrass could conserve water Deseret News, retrieved Sept 20, 2011
- What’s New From What’s From Buff To Blue: Grasses For a Green Environment University of Nebraska –Lincoln, retrieved Jan 31, 2911
- LE Trenholm and KevinKenworthy Captiva St. Augustine Grass University of Florida
- J. B. Unruh, L. E. Trenholm, and J. L. Cisar Centipedegrass for Florida Lawns
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