What is Topsoil

A common misconception when buying topsoil is that the soil you receive should be a dark, fertile, friable loam capable of serving all of our landscaping needs. To further complicate matters, most people think that the darker the topsoil the better this is not always the case, the terms “topsoil” and “loam” are often used interchangeably when, in fact, not all topsoils are loams and not all loams are topsoils.

Soil is the foundation of our landscape. It is comprised of sand, silt and clay, mixed with varying amounts of organic matter, water and air. It is a complex and dynamic medium, able to serve many functions.

Topsoil, as the name infers, is the uppermost layer of soil. The surface soil usually is darker in color than the subsoil below it because of the accumulation of organic matter. Virgin topsoils generally range from 0 to 5 inches in thickness. Most soils, however, have been plowed so a more functional definition of topsoil is the depth of soil that has been mixed by normal cultivation practices, in most cases 5 to 12 inches.

Loam, on the other hand, is a textural classification. Texture refers to the relative amount of sand, silt and clay in a soil. A loam is technically a soil with between 7% and 27% clay, 28% to 50% silt and less than 52% sand. One may modify the term, loam, to sandy loam, sandy clay loam, clay loam, silty clay loam or silt loam as the proportions of these individual soil fractions change.

What to Look For...
Before one buys any topsoil it is a good idea to visually inspect the stockpiled soil. It should be free of trash and other debris.

Texture:
Soil texture greatly affects the suitability of topsoil. Sands should be avoided because they almost always have a low water- and nutrient-holding capacity. Clays, sandy clays, silty clays and silts should be avoided because they tend to be difficult to cultivate (cloddy) and insufficiently permeable to water and air. In other words, they tend to stay wet too long after a rain, which prevents air from reaching plants roots. Soil textures that may be suitable for topsoil include loamy sands, sandy loams (including fine sandy loams), loams, silt loams, silty clay loams, clay loams and sandy clay loams. Loamy sands have the disadvantage of having a relatively low water-holding capacity but are generally easier to till. Because they tend to resist compaction, loamy sands may be preferred in areas subject to traffic or other conditions that may result in soil compaction.

Organic Matter:
Topsoils should contain at least 2% organic matter but no more than about 10%. Organic matter is an important component of topsoils. It contributes to the capacity of soils to hold water and nutrients and tends to improve soil aggregation which makes soils more porous. This results in excess water draining away more readily and facilitates the flow of air to plants roots. Organic matter also tends to make soils easier to till. Too much organic matter, however, may result in a soil that is subject to compaction during the installation phase or afterwards as a result of normal foot traffic.

When buying topsoil, a preconceived notion is the darker, the better. While an increase in darkness is often associated with an increase in organic matter, soils which are very dark and grayish may have been dredged from wetland areas. These soils often are very acidic and poorly structured. They “evolved” under wet conditions and may not respond well when placed in a well-aerated environment. Avoid them.
Amendments

It is usually unrealistic to believe that purchased topsoil will require no amendments. Lime and fertilizer are frequently necessary. The addition of organic matter can greatly improve the soil’s physical condition. Two or three inches of organic matter tilled to a depth of 6 to 8 inches is a typical recommendation for topsoils low in organic matter. Sources of organic matter include screened compost, peat moss, manure, leaf-mold, rotted sawdust and cover crops. The characteristics of each of these must be considered before use. Mushroom composts, for instance, should be checked for high soluble salt levels. Although it is tempting to add sand to a “heavy” soil, adding organic matter will ultimately give the best results.

Topsoil is generally sold by the cubic yard. The minimum amount commonly delivered is from 3 to 6 yards. Most soils are screened through a 3/4-inch mesh. Unscreened soil is less expensive than screened, but the few dollars saved is rarely worth the time and effort spent removing coarse fragments after delivery. Estimate the amount needed by figuring 12 cubic yards will cover about 1000 square feet to the depth of 4 inches. Rural companies may mix compost or manure with the topsoil. “Manufactured” topsoil is a more recent market development. It is commonly a coarse-grained (sandy) mineral base mixed with some composted organic material. This serves a dual function of providing a potentially useful horticultural product and disposing of bulky organic wastes. Not all are worthy of consideration as topsoil.

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How Big Are Bama Dirt Trucks?
Our trucks are single axle and are 8 feet wide and 8 feet tall, they are about the same width as a F350 dually pickup truck. Unlike the big trucks that will crack your concrete or asphalt driveway you don’t have to worry about us driving on them because our trucks are only single axle and are much lighter. We have the largest “Single Axle Dump Trucks” available, that means we can get in the tightest spots to deliver material and get right back out again where big trucks would never dream of going.

How much can we haul on the truck?
5 yards is the most volume we can haul on the truck most needs are for 5 yards and it seems to be just the right amount.


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