The term sod may be used to mean turf grown and cut specifically for the establishment of lawns. However, 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), or avoided altogether, due to the alternative offensive meaning of the word "sod".
Sod (or turf) for lawns is grown on specialist farms. It is usually grown locally to avoid long transport and drying out and heat buildup of the product. It is sold to landscapers, home builders or home owners who use it to establish a lawn quickly and avoid soil erosion. 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. 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 rolls. Some large sod farms may export internationally. Because of the product's short life after harvest, the sod may be washed clean of the soil down to the bare roots (or sprigs) which makes shipping lighter and cheaper. Sod can be used to repair a small area of lawn that has died.
Seed may be blown about by the wind, eaten by birds, or fail due to 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.
Turf is however more expensive, and requires considerably more water for its establishment.
In the first variation, called the tiller-to-the-grass technique, only the top grass is tilled off and the tilled grass is hauled away leaving just soil on which to apply the sod – no grass remains. The remaining soil may be retilled. This creates a smooth and loose bed on which to install the sod. Some landscapers prefer this smooth and loose bed.
In the second variation, called the till-it-all technique, existing grass as well as the soil underneath holding the grass are tilled together. The old grass is in effect mixed in with the existing soil creating the surface on which the sod will be installed. Some landscapers prefer this method because it creates the bed on which the sod is installed upfront and without further effort.
Some prefer not to use a tiller to prepare the area to be sodded. They claim that if a neighbor or children were to walk over the newly established sod in the first few days after the installation, the turf would become uneven. The claim is that the soil underneath is still very loose.
Some don't like this technique out of concern that any weeds that existed in the previous lawn may remain to affect the new lawn. Also some fear that the existing lawn will need to be aerated so the roots of the sod will have somewhere to "catch" on to. However, the technique is used with equally successful results, or better, as the other three sod application methods.
Sod has occasionally been cut out in blocks to use as a building material, especially in grasslands where grass is plentiful and few other materials are available. For use as a building material, sods are cut out in regular block shapes and laid like brickwork, although for strength blocks of sod are usually much longer and wider than typical bricks. This construction was common during nineteenth century settlements of the Canadian and American prairies. Common dimensions of sod blocks used in these pioneer abodes were 2 ft by 1 ft by 6 in (600 × 300 × 150 mm). Cutting sods for building may be done with a spade and axe, but for large scale work a modified plough is used.
The bare sod is prone to damage from rain or being knocked down, so the outer walls are usually protected with a layer of stucco or wood paneling. Similarly, bare sod inside is dirty, so the interior may be lined with canvas, tarpaper, or plaster. A variety of roofing methods can be used, and the house can be fitted with conventional windows and doors. Sod houses have the advantages of being very cheap, and well insulated, so that they are cool in summer and warm in winter. The main disadvantages are that they tend to be damp, and deteriorate quickly unless maintained.
Sod has also been used in fortification. Blockhouses have been constructed from sod, and it has also been used to make very effective berms or low defensive walls. The Roman-built Antonine Wall in Scotland was largely made from sod.
Because of its cheapness and availability, sod walls could easily be made thick enough to be bulletproof.