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[This summary has been extracted, with permission, from a report by the USDA Risk Management Agency, Risk and Evaluation Divisions; the full report is available on: http://www.act.fcic.usda.gov/research/feasible.html
To contact the agency:
United States Department of Agriculture
Risk Management Agency/Risk Management Education
Room 6755, Stop Code 0803
1400 Independence Avenue, SW
Washington, DC 20250-0803
The Census reported 218,161 harvested acres of U.S. sod production in 1992, up 19 percent from the prior census year, 1987. The five leading sod-producing states in 1992, ranked by acreage, were Florida, Texas, Alabama, Minnesota, and Georgia. These states represent about half of the total U.S. sod acreage.
The most common turfgrass species grown in the U.S. include bermuda grass, bluegrass, centipede grass, fine fescue, Kentucky bluegrass, ryegrass, St. Augustine grass, tall fescue, and zoysia grass. The housing industry is the primary market for turfgrass sod, and the greatest demand is in metropolitan areas. Other major markets include land developers, golf courses, parks, cemeteries, athletic fields, and schools.
Virtually all sod is produced domestically because climatic conditions need to be similar in producing and consuming areas. The average trucking distance from shipping point to landscape site is about 150 to 180 miles. Climatic conditions generally do not change significantly within this radius.
Sod is classified into two general categories: cool-season grasses (such as bluegrass and tall fescue) and warm-season grass (including bermuda grass and zoysia grass). Cool-season grasses grow best in the northern parts of the U.S., as well as in areas with higher elevations and coastal regions where evening summer temperatures are in the 10 to 16 C range. Warm-season grasses are usually grown from lower Florida and along the Gulf Coast northwards, throughout the upper South.
Sod can be established either by vegetative propagation or direct seeding. In general, warm-season grasses are established with vegetative propagation using sprigs or plugs, while cool-season grasses are direct seeded. Sod may be produced in blends or mixtures of two or more grasses, particularly for those species established through seeding. Each type of grass responds differently to various stresses, and when blended or mixed, the more tolerant grass will dominate, increasing overall turf performance.
Generally, grass seed germinates best when soil temperatures are 10 C or less. Root development from sprigs requires higher temperatures. Growers irrigate and fertilise to promote rapid production of quality sod and to protect against stand failure. Mowing is used to control weeds, remove excess growth, improve root growth, and promote lateral growth of the turfgrass. Infrequent mowing can cause the stand to become thin and aesthetically unacceptable. It can also result in increased frequency of losses due to disease.
Marketable sod is typically produced in 6 to 24 months. Sod is ready for harvest when it has both green leaves and an actively growing root system. The actual growing period depends on soil type, moisture, temperature, grass species, fertilisation, and other cultivation practices. Sod is harvested on demand and is cut only to meet a particular days' orders. During periods of low prices, many sod growers put their fields under low maintenance for several years. By using this method, they hope to sell at higher prices at a later time, rather than harvesting the sod at a loss or abandoning their fields.
Sod is cut with 1/2- to 5/8-inch of soil attached. This thinness allows for easier handling, permits more rapid establishment, and requires less expense in transportation costs than if cut thicker. If cut much thinner, it will be difficult to retain enough moisture to keep the sod fresh until installation. The two basic techniques for sod harvesting are the ribbon-cut method and the clean-cut method. The application of a particular method depends on the type of grass. Ribbon cutting is normally used for all warm-season grasses and is used to re-establish turf. When ribbon cutting is used, 1- to 2-inch-wide undisturbed turf ribbons or strips are left in the field between the harvested strips. Clear cutting, on the other hand, does not leave ribbons or surface vegetation and is normally used on cool- season grasses which are re-seeded after harvest.
Major production perils include drought, excess heat, and excess moisture. Although many sod growers irrigate, prolonged dry conditions may cause ponds and streams, a major source of water, to dry up. While many insects and diseases may affect turfgrass sod, the problems they create can generally be controlled through management practices.
Disaster payment data indicate which sod-growing areas received large payments relative to their acreage. For example, Missouri's share of U.S. sod acreage in recent years, at about 2 percent, was far less than their share of ad hoc disaster payments, at 18 percent. Similar situations are apparent in analysis of Maryland and Tennessee data. In contrast, Florida, Texas, and Alabama collected a smaller share of ad hoc payments relative to their acreage.
Our assessment is that, although there would likely be moderate interest among turfgrass producers in buying insurance for sod, participation is likely to be lower than for most crops. One reason for lower interest among sod growers is that most sod is irrigated. Production losses from erosion and flooding were also cited as occasional production perils.
The acreage subject to losses from flooding, however, is likely to be quite small. On a regional basis, we judge that participation in a sod insurance program would be greatest in the North Central states. The basis for this judgement is the large amount of ad hoc disaster assistance payments for sod reported for this region over the 1988-93 period. Most of the losses were caused by drought and floods. In addition, the largest amount of non- irrigated sod is located in the North Central region.
Any claims made by authors in the Australian New Crops Newsletter are presented by the Editors in good faith. Readers would be wise to critically examine the circumstances associated with any claims to determine the applicability of such claims to their specific set of circumstances. This material can be reproduced, with the provision that the source and the author (or editors, if applicable) are acknowledged and the use is for information or educational purposes. Contact with the original author is probably wise since the material may require updating or amendment if used in other publications. Material sourced from the Australian New Crops Newsletter cannot be used out of context or for commercial purposes not related to its original purpose in the newsletter
Contact: Dr Rob Fletcher, School of Land and Food, The University of Queensland Gatton College, 4345; Telephone: 07 5460 1311 or 07 5460 1301; Facsimile: 07 5460 1112; International facsimile: 61 7 5460 1112; Email:email@example.com
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originally created by:GK; latest update 17 October 2001 by: RF