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Related to loam: clay loam, silt loam


soil composed of sand, silt, clay, and organic matter in evenly mixed particles of various sizes. More fertile than sandy soils, loam is not stiff and tenacious like clay soils. Its porosity allows high moisture retention and air circulation. The popular confusion of loam with humushumus
, organic matter that has decayed to a relatively stable, amorphous state. It is an important biological constituent of fertile soil. Humus is formed by the decomposing action of soil microorganisms (e.g.
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 is probably due to the superior quality of both soils. According to the preponderance of their ingredients, loams are classified as sandy, clay, or silt loams. Most soils of agricultural importance are some type of loam.
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a friable sandy and clayey sedimentary rock containing 10–30 percent (by weight) clay particles smaller than 0.005 mm. In soil science, loam with a higher clay content is called heavy loam, and that with less clay is called light loam. A distinction is made between coarse sandy, fine sandy, and silty loam, depending on the content of (1) sand grains of the corresponding size and (2) silty, or aleurite, particles.

The mineralogical composition of loam is varied: the more sandy loan has a high quartz content, whereas the more clayey type contains clay minerals, such as kaolinite, illite, and montmorillonite. Loam is sometimes rich in organic substances; in arid regions it may be rich in water-soluble salts. The origin of loam is usually continental; the corresponding ocean deposits are called sandy or aleurite clays. Loam is often used as a raw material for the production of brick.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


Soil mixture of sand, silt, clay, and humus.
Molding material consisting of sand, silt, and clay used over backup material for producing massive castings, usually of iron or steel.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


In building construction, a mixture composed chiefly of moistened clay, sand, and silt, or some mixture including these ingredients. Once used as a mortar when combined with lime, or used as a plaster with the addition of chopped straw.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.


1. rich soil consisting of a mixture of sand, clay, and decaying organic material
2. a paste of clay and sand used for making moulds in a foundry, plastering walls, etc.
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
At higher aeration porosity, (a > 0.15 [m.sup.3][m.sup.-3]), [D.sub.p/[D.sub.0] is higher for the clay loam soil.
The maximum value of pH was found in mound soil of clay loam (7.67+-0.07) while minimum value was found in soil type (loam) (7.46+-0.05).
Highest 1.17 and 1.15 mg/kg were recorded in plants grown in clay loam soils in trials 1 and 2, respectively.
In figure 7 is shown graph and map of vibration spread in the loam soil.
The soil of Gojra are predominantly loam followed by silt loam, silt clay loam, and slid at depths 0-15, 15-30, 30-45, 45-60 and 60-75 cm respectively (Table 3).
Soils with sandy loam and sandy clay loam textures have Pearson's correlation coefficients ranging from medium to high (r = -0.65 and -0.91), respectively (Figure 2A, 2B).
Burrows were located mostly in loam soil on stony rises but others were in clay soil.
Those taking advantage of the latest housing boom could well find that the topsoil removed during construction is often returned as a mixture of loam and builders rubble.
Soil texture is classified into three classes ranging from slight (clay, sandy clay, silty clay) to moderate (sandy clay loam, clay loam, silt clay loam, loamy sand) and high (loam, silt loand, sandy loam) erodibility.
"These clay loam sediments have a larger surface area available for the chemical reactions that bind the phosphorus to the sediments," Smith explains.
Figure 1 shows the effect of moisture content on the coefficient of soil-interface friction of Sandy clay loam soil (S1).
The seed, loam, fertilizer and stone and gravel mix were purchased with funds confiscated from drug dealers.