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condition of the soil or subsoil in which the soil grains become cemented together by such bonding agents as iron oxide and calcium carbonate, forming a hard, impervious mass. It is disadvantageous to farming, interfering with the circulation of moisture in the soil and with the growth of roots through the soil. When the condition is caused by the filling of the air spaces in the soil with fine particles of clay, the subsoil is called a clay pan. This usually occurs in acid soil.


An extremely hard soil containing gravel and boulders.




An extremely dense hard layer of soil, boulder clay, or gravel; difficult to excavate.
References in periodicals archive ?
In this work ordinary kriging, a type of geostatistical techniques is applied for mapping apparent resistivity at Sidi Chennane, one of phosphatic basins in Morocco, which is characterized by the presence of sterile hardpan -so-called "disturbances"- hard to detect.
In a rice-wheat cropping system, rice is mostly grown under puddle condition which leads to the dispersion of soil aggregates by plowing, sealing of pore spaces, and formation of a subsurface hardpan (Hassan and Gregory, 1999).
When small lakes dry up, they leave a salt crust or hardpan.
Rototillers fluff up the soil down to about seven inches and then leave you with hardpan beneath.
But when faced with a 300-yard shot at a Kudu across a flat hardpan, my PH literally forced his sticks on me.
Engineered to withstand high stress, the TCT Series is ideal for drilling in soft sandstone or limestone formations, caliche, hardpan and other tough materials.
Active Head Mole piercing tools boasts of a reciprocating head design characterized by a double-strike system that uses the initial impact force to increase production in difficult soils such as cobble, hard clay and hardpan.
Desert and chaparral soils are relatively shallow with no distinct soil profiles (Table 5) due to the presence of hardpan (Specht 1968).
From these sources, Sears concluded that Ohio prairies resulted from successional changes where aquatic habitats decreased as the substrate became drier and plants of prairie communities became established on thick, boulder-free, fine silt soil underlain by a hardpan, with a depth of 100 feet or more to bedrock.
Estos suelos presentan areas extensas de antiguos flujos de lava que forman una capa relativamente impermeable, denominada Talpetate en nahua y hardpan en ingles (Williams, 1994), de profundidad variable entre muy cerca de la superficie y dos metros, que puede limitar el crecimiento de las raices y la capacidad de la vegetacion para resistir los periodos de sequia (Barrance et al.
Palis & Fischer (1997) found that off-road vehicle use disrupts pond floor microtopography by breaking the hardpan that lies below the pond and causing a shorter hydroperiod, thus decreasing the availability of ephemeral ponds for breeding amphibians.