Also found in: Thesaurus, Encyclopedia, Wikipedia.


1. A layer of hard subsoil or clay. Also called caliche.
2. Hard, unbroken ground.
3. A foundation; bedrock.


(Physical Geography) a hard impervious layer of clay below the soil, resistant to drainage and root growth



1. any layer of firm detrital matter, as of clay, underlying soft soil.
2. hard, unbroken ground.


A compacted layer of soil that is difficult for roots or water to penetrate. It often forms just below the depth of plowing, when plowing, year after year, is always to the same depth.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.hardpan - crust or layer of hard subsoil encrusted with calcium-carbonate occurring in arid or semiarid regions
dirt, soil - the part of the earth's surface consisting of humus and disintegrated rock
References in periodicals archive ?
Scraper boxes are king when it comes to hardpan and clay.
Back then, the property was 17 acres of wild, untamed plants and unworkable hardpan clay soil.
Though maybe it's the canal, misting with sunup and grown salty from runoff escaping this alkaline hardpan.
Breaking up the hardpan and mixing the soil likely resulted in greater crop residue input at a depth of 20-30cm under the RUR, RUU and UUU systems than under RRR.
From well drilling records available at the University of Michigan Biological Station (UMBS), the subsurface geology between Douglas Lake and Burt Lake contains poorly sorted layers of sand, gravel, and sandy-gravel separated by layers of hardpan clay of various thicknesses.
With its very large taproot that can reach up to 6 feet deep, this is a star at breaking up hardpan soil and increasing water absorption in compacted soil.
I passed a big hardpan turn-out in front of a cattle gate and holding pen.
Canizares, from Malaga, Spain, won on the second extra hole when the 27-year old Hinton from Oxford, England, pitched short from a hardpan and chipped about 15 feet past the cup.
Soil characteristics that may change across a soil series include effective rooting depth, depth to bedrock or hardpan, soil texture and depth of distinct soil horizons.
Where the need exists, funds are requested for additional sanitary /shower facilities, additional campsites, expanded (or additional) playgrounds, and the addition of electric, sewer and water for campsites and the re-vegetation of campsite hardpan areas.
If you plan to plant deep-rooting plants such as carrots (some varieties) and parsnips, prepare the soil deeply, remove stones and break up any layers of hardpan to allow for deep root penetration.
The geological investigations carried out in Sidi Chennane phosphatic deposit in the Oulad Abdoun basin revealed a phenomenon of sterile hardpan [Bakkali 2005, Baba & al.