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REVIEW

Hardsetting soils: a review

Ian G. Daniells
+ Author Affiliations
- Author Affiliations

NSW Department of Primary Industries, Tamworth Agricultural Institute, 4 Marsden Park Road, Calala, NSW 2340, Australia; Current address: 195 Sandy Road, Kootingal, NSW 2352, Australia. Email: janinadaniells1949@dodo.com.au

Soil Research 50(5) 349-359 https://doi.org/10.1071/SR11102
Submitted: 10 May 2011  Accepted: 5 July 2012   Published: 8 August 2012

Abstract

Hardsetting soils have been defined as soils that set to a hard, structureless mass during drying and are thereafter difficult or impossible to cultivate until the profile is rewetted. Soil strength increases rapidly as the soil dries, and so seedlings must grow quickly before soil strength becomes too high for root growth or shoot emergence. Recent work on the mechanisms of hardsetting confirms that aggregate disruption through slaking and dispersion on wetting leads to coalescence. Bridging by dispersed particles under matric potential makes a soil hardset. Failure to recover from a coalesced state as the soil dries leaves it with a massive structure. This paper reviews the worldwide occurrence of hardsetting soils, the evolution of definitions of hardsetting, and the use of those definitions in soil classification with particular emphasis on Australia. Measurement of hardsetting includes methods such as visual score of slaking and dispersion, penetration resistance, fall-cone penetration, dispersion, fractions of soil organic matter, friability index, modulus of rupture, and a particular use of the soil water retention curve. Overcoming problems associated with hardsetting soils and their ongoing management is difficult. Further work is needed on the reasons for variable responses to tillage, no tillage, and pasture. Modifying soil texture has limited application, and increasing soil organic matter under cropping is difficult in low-rainfall areas. Polymers have been shown to be beneficial. Mulching maintains higher soil moisture and therefore a softer surface, while biochar shows inconsistent effects. Controlled traffic is a key to reducing recompaction. Management of a hardsetting soil must include the whole rotation, including when to till, when to crop, and when to graze or not.

Additional keywords: hard setting, hard-setting.


References

Aylmore LAG, Sills ID (1982) Characterization of soil structure and stability using modulus of rupture–exchangeable sodium percentage relationships. Australian Journal of Soil Research 20, 213–224.
Characterization of soil structure and stability using modulus of rupture–exchangeable sodium percentage relationships.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL38XlsVeltLo%3D&md5=371d44a81a288179abe41ae42ff9b987CAS |

Barber RG, Navarro F (1994) The rehabilitation of degraded soils in Eastern Bolivia by subsoiling and the incorporation of cover crops. Land Degradation & Development 5, 247–259.
The rehabilitation of degraded soils in Eastern Bolivia by subsoiling and the incorporation of cover crops.Crossref | GoogleScholarGoogle Scholar |

Becher HH, Breuer J, Klingler B (1997) An index value for characterizing hardsetting soils by fall-cone penetration. Soil Technology 10, 47–56.
An index value for characterizing hardsetting soils by fall-cone penetration.Crossref | GoogleScholarGoogle Scholar |

Blackwell PS (Ed.) (1992) Slaking and hardsetting soils: some research and management aspects. Soil & Tillage Research 25, 111–261.
Slaking and hardsetting soils: some research and management aspects.Crossref | GoogleScholarGoogle Scholar |

Bolland MDA, Baker MJ, Wilson IR (1994) Soil phosphorus testing: 2. Assessment of a rotary blade soil sampler for collecting soil samples to measure soil test phosphorus. Communications in Soil Science and Plant Analysis 25, 2385–2394.
Soil phosphorus testing: 2. Assessment of a rotary blade soil sampler for collecting soil samples to measure soil test phosphorus.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXltVOgs7k%3D&md5=22a41d040faa84ba585af7c46f8d11a5CAS |

Bresson LM, Moran CJ (2003) Role of compaction versus aggregate disruption on slumping and shrinking of repacked hardsetting seedbeds. Soil Science 168, 585–594.
Role of compaction versus aggregate disruption on slumping and shrinking of repacked hardsetting seedbeds.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXmtlamu7k%3D&md5=74f52f430830ce59c524439f2f212176CAS |

Bresson LM, Moran CJ (2004) Micromorphological study of slumping in a hardsetting seedbed under various wetting conditions. Geoderma 118, 277–288.
Micromorphological study of slumping in a hardsetting seedbed under various wetting conditions.Crossref | GoogleScholarGoogle Scholar |

Brown TH, Mahler RL (1988) Relationships between soluble silica and plow pans in Palouse silt loam soils. Soil Science 145, 359–364.
Relationships between soluble silica and plow pans in Palouse silt loam soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1cXlsVynt7w%3D&md5=ad2870d6d94e1892c71d6fac8ddd4558CAS |

Brown KW, Evans GB, Thomas JC (1985) Increased soil water retention by mixing horizons of shallow sandy soils. Soil Science 139, 118–121.
Increased soil water retention by mixing horizons of shallow sandy soils.Crossref | GoogleScholarGoogle Scholar |

Caron J, Kay BD (1992) Rate of response of structural stability to a change in water content: Influence of cropping history. Soil & Tillage Research 25, 167–185.
Rate of response of structural stability to a change in water content: Influence of cropping history.Crossref | GoogleScholarGoogle Scholar |

Chan KY (1995) Strength characteristics of a potentially hardsetting soil under pasture and conventional tillage in the semi-arid region of Australia. Soil & Tillage Research 34, 105–113.
Strength characteristics of a potentially hardsetting soil under pasture and conventional tillage in the semi-arid region of Australia.Crossref | GoogleScholarGoogle Scholar |

Chan KY (2001) Soil particulate organic carbon under different land use and management. Soil Use and Management 17, 217–221.
Soil particulate organic carbon under different land use and management.Crossref | GoogleScholarGoogle Scholar |

Chan KY, Sivapragasam S (1996) Amelioration of a degraded hardsetting soil using an anionic polymeric conditioner. Soil Technology 9, 91–100.
Amelioration of a degraded hardsetting soil using an anionic polymeric conditioner.Crossref | GoogleScholarGoogle Scholar |

Chan KY, Bowman AM, Smith W, Ashley R (2001) Restoring soil fertility of degraded hardsetting soils in semi-arid areas with different pastures. Australian Journal of Experimental Agriculture 41, 507–514.
Restoring soil fertility of degraded hardsetting soils in semi-arid areas with different pastures.Crossref | GoogleScholarGoogle Scholar |

Chan KY, Van Zwieten L, Meszaros I, Downie A, Joseph S (2007) Agronomic values of greenwaste biochar as a soil amendment. Australian Journal of Soil Research 45, 629–634.
Agronomic values of greenwaste biochar as a soil amendment.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXhsVamtbnM&md5=c3c2d1da42f58b40a178f0a1095cd259CAS |

Chan KY, Van Zwieten L, Meszaros I, Downie A, Joseph S (2008) Using poultry litter biochars as soil amendments. Australian Journal of Soil Research 46, 437–444.
Using poultry litter biochars as soil amendments.Crossref | GoogleScholarGoogle Scholar |

Cochrane HR, Aylmore LAG (1991) Assessing management-induced changes in the structural stability of hardsetting soils. Soil & Tillage Research 20, 123–132.
Assessing management-induced changes in the structural stability of hardsetting soils.Crossref | GoogleScholarGoogle Scholar |

Cochrane HR, Aylmore LAG (2002) Modulus of rupture. In ‘Soil physical measurement and interpretation for land evaluation’. Australian Soil and Land Survey Handbook Series, Vol. 5. (Eds NJ McKenzie, KJ Coughlan, HP Cresswell) pp. 278–291. (CSIRO Publishing: Melbourne)

Cochrane HR, Scholz G, Van Vreswyk AME (1994) Sodic soils in Western Australia. Australian Journal of Soil Research 32, 359–388.
Sodic soils in Western Australia.Crossref | GoogleScholarGoogle Scholar |

Cockroft B, Olsson KA (2000) Degradation of soil structure due to coalescence of aggregates in no-till, no-traffic beds in irrigated crops. Australian Journal of Soil Research 38, 61–70.
Degradation of soil structure due to coalescence of aggregates in no-till, no-traffic beds in irrigated crops.Crossref | GoogleScholarGoogle Scholar |

Collis-George N, Laryea K (1971) Infiltration behaviour of structurally unstable soils under ponded and non-ponded conditions. Australian Journal of Soil Research 9, 7–20.
Infiltration behaviour of structurally unstable soils under ponded and non-ponded conditions.Crossref | GoogleScholarGoogle Scholar |

Connolly RD, Freebairn DM, Bridge BJ (1997) Change in infiltration characteristics associated with cultivation history of soils in south-eastern Queensland. Australian Journal of Soil Research 35, 1341–1358.
Change in infiltration characteristics associated with cultivation history of soils in south-eastern Queensland.Crossref | GoogleScholarGoogle Scholar |

Dexter AR (2004a) Soil physical quality: Part I. Theory, effects of soil texture, density, and organic matter, and effects on root growth. Geoderma 120, 201–214.
Soil physical quality: Part I. Theory, effects of soil texture, density, and organic matter, and effects on root growth.Crossref | GoogleScholarGoogle Scholar |

Dexter AR (2004b) Soil physical quality: Part II. Friability, tillage, tilth and hard-setting. Geoderma 120, 215–225.
Soil physical quality: Part II. Friability, tillage, tilth and hard-setting.Crossref | GoogleScholarGoogle Scholar |

Doyle RB, Habraken FM (1993) The distribution of sodic soils in Tasmania. Australian Journal of Soil Research 31, 931–947.
The distribution of sodic soils in Tasmania.Crossref | GoogleScholarGoogle Scholar |

Fabiola N, Giarola B, Silva AP, Imhoff S, Dexter AR (2003) Contribution of natural soil compaction on hardsetting behavior. Geoderma 113, 95–108.
Contribution of natural soil compaction on hardsetting behavior.Crossref | GoogleScholarGoogle Scholar |

Ferguson SA, Fielke JM, Riley TW (1998) Wear of cultivator shares in abrasive South Australian soils. Journal of Agricultural Engineering Research 69, 99–105.
Wear of cultivator shares in abrasive South Australian soils.Crossref | GoogleScholarGoogle Scholar |

Finlay MJ, Tisdall JM, McKenzie BM (1994) Effect of tillage below the seed on emergence of wheat seedlings in a hardsetting soil. Soil & Tillage Research 28, 213–225.
Effect of tillage below the seed on emergence of wheat seedlings in a hardsetting soil.Crossref | GoogleScholarGoogle Scholar |

Ford GW, Martin JJ, Rengasamy P, Boucher SC, Ellington A (1993) Soil sodicity in Victoria. Australian Journal of Soil Research 31, 869–909.
Soil sodicity in Victoria.Crossref | GoogleScholarGoogle Scholar |

Franzmeier DP, Chartres CJ, Wood JT (1996) Hardsetting soils in southeast Australia: landscape and profile processes. Soil Science Society of America Journal 60, 1178–1187.
Hardsetting soils in southeast Australia: landscape and profile processes.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28Xktl2qsbg%3D&md5=0036107db5bcffe9113eda31778850ddCAS |

Ghezzehei TA, Or D (2000) Dynamics of soil aggregate coalescence governed by capillary and rheological processes. Water Resources Research 36, 367–379.
Dynamics of soil aggregate coalescence governed by capillary and rheological processes.Crossref | GoogleScholarGoogle Scholar |

Giarola NFB, Silva AP (2002) Concepts on “coesos” and hardsetting soils. Scientia Agricola 59, 613–620.
Concepts on “coesos” and hardsetting soils.Crossref | GoogleScholarGoogle Scholar |

Golchin A, Clarke P, Oades JM, Skjemstad JO (1995) The effects of cultivation on the composition of organic matter and structural stability of soils. Australian Journal of Soil Research 33, 975–993.
The effects of cultivation on the composition of organic matter and structural stability of soils.Crossref | GoogleScholarGoogle Scholar |

Grant CD, Angers DA, Murray RS, Chantigny MH, Hasanah U (2001) On the nature of soil aggregate coalescence in an irrigated swelling clay. Australian Journal of Soil Research 39, 565–575.
On the nature of soil aggregate coalescence in an irrigated swelling clay.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXks1KqtLg%3D&md5=50e4c1b78bed381175536d305ee2b5dcCAS |

Hall DJM, McKenzie DC, MacLeod DA, Barrett A (1994) Amelioration of a hardsetting Alfisol through deep mouldboard ploughing, gypsum application and double cropping. I. Soil physical and chemical properties. Soil & Tillage Research 28, 253–270.
Amelioration of a hardsetting Alfisol through deep mouldboard ploughing, gypsum application and double cropping. I. Soil physical and chemical properties.Crossref | GoogleScholarGoogle Scholar |

Harper RJ, Gilkes RJ (1994) Hardsetting in the surface horizons of sandy soils and its implications for soil classification and management. Australian Journal of Soil Research 32, 603–619.
Hardsetting in the surface horizons of sandy soils and its implications for soil classification and management.Crossref | GoogleScholarGoogle Scholar |

Harper RJ, Gilkes RJ (2004) The effects of clay and sand additions on the strength of sandy topsoils. Australian Journal of Soil Research 42, 39–44.
The effects of clay and sand additions on the strength of sandy topsoils.Crossref | GoogleScholarGoogle Scholar |

Hudson NW (1987) ‘Soil and water conservation in semi-arid areas.’ FAO Corporate Document Repository. (Food and Agriculture Organization of the United Nations: Rome) http://www.fao.org/docrep/T0321E/t0321e-11.htm

Hulugalle NR (1990) Alleviation of soil constraints to crop growth in the upland Alfisols and associated soil groups of the West African Sudan savannah by tied ridges. Soil & Tillage Research 18, 231–247.
Alleviation of soil constraints to crop growth in the upland Alfisols and associated soil groups of the West African Sudan savannah by tied ridges.Crossref | GoogleScholarGoogle Scholar |

Hulugalle NR, Friend JJ, Kelly R (2002) Some physical and chemical properties of hardsetting Alfisols can be affected by trickle irrigation. Irrigation Science 21, 103–113.
Some physical and chemical properties of hardsetting Alfisols can be affected by trickle irrigation.Crossref | GoogleScholarGoogle Scholar |

Hulugalle NR, Jaya R, Luther GC, Ferizal M, Daud S, Yatiman , Irhas , Yufniati ZA, Feriyanti F, Tamrin , Han B (2009) Physical properties of tsunami-affected soils in Aceh, Indonesia: 2½ years after the tsunami. Catena 77, 224–231.
Physical properties of tsunami-affected soils in Aceh, Indonesia: 2½ years after the tsunami.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjsFemtLk%3D&md5=cbb4beb3982ff8078ad9a069363a4329CAS |

Igwe CA, Zarei M, Stahr K (2006) Clay dispersion of hardsetting inceptisols in Southeastern Nigeria as influenced by soil components. Communications in Soil Science and Plant Analysis 37, 751–766.
Clay dispersion of hardsetting inceptisols in Southeastern Nigeria as influenced by soil components.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xjs1Oqs78%3D&md5=41d36eb0079483480e48c2be1edaa5b8CAS |

Igwe CA, Zarei M, Stahr K (2009) Colloidal stability in some tropical soils of southeastern Nigeria as affected by iron and aluminium oxides. Catena 77, 232–237.
Colloidal stability in some tropical soils of southeastern Nigeria as affected by iron and aluminium oxides.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjsFemtb4%3D&md5=834c6b5c69025e3a533e840890467106CAS |

Isbell RF (1995) Sealing, crusting and hardsetting conditions in Australian soils. In ‘Proceedings of 2nd International Symposium on Sealing, Crusting and Hardsetting Soils: Productivity and Conservation’. (Eds HB So, GD Smith, SR Raine, BM Schaffer, RJ Loch) pp. 15–30. (Australian Society of Soil Science Inc., Queensland Branch: Brisbane)

Isbell RF (1996) ‘The Australian Soil Classification’. (CSIRO Publishing: Melbourne)

Isbell RF, McDonald WS, Ashton LJ (1997) Diagnostic horizons and materials. In ‘Concepts and rationale of the Australian Soil Classification’. pp. 12–38. (ACLEP, CSIRO Land and Water: Canberra)

Kayombo B, Lal R (1993) Tillage systems and soil compaction in Africa. Soil & Tillage Research 27, 35–72.
Tillage systems and soil compaction in Africa.Crossref | GoogleScholarGoogle Scholar |

Ley GJ, Laryea KB (1994) Spatial variability in penetration resistance of a hardsetting tropical Alfisol. Soil & Tillage Research 29, 367–381.
Spatial variability in penetration resistance of a hardsetting tropical Alfisol.Crossref | GoogleScholarGoogle Scholar |

Lima HV, Silva AP, Santos MC, Cooper M, Romero RE (2006) Micromorphology and image analysis of a hardsetting Ultisol (Argissolo) in the state of Ceara (Brazil). Geoderma 132, 416–426.
Micromorphology and image analysis of a hardsetting Ultisol (Argissolo) in the state of Ceara (Brazil).Crossref | GoogleScholarGoogle Scholar |

Macks SP, Murphy BW, Cresswell HP, Koen TB (1996) Soil friability in relation to management history and suitability for direct drilling. Australian Journal of Soil Research 34, 343–360.
Soil friability in relation to management history and suitability for direct drilling.Crossref | GoogleScholarGoogle Scholar |

Materechera SA (2009) Aggregation in a surface layer of a hardsetting and crusting soil as influenced by the application of amendments and grass mulch in a South African semi-arid environment. Soil & Tillage Research 105, 251–259.
Aggregation in a surface layer of a hardsetting and crusting soil as influenced by the application of amendments and grass mulch in a South African semi-arid environment.Crossref | GoogleScholarGoogle Scholar |

McDonald RC, Isbell RF (1990) Soil profile. In ‘Australian soil and land survey field handbook’. 2nd edn. (Eds RC McDonald, RF Isbell, SG Speight, J Walker, MS Hopkins) pp. 103–152. (Inkata Press: Melbourne)

McDonald RC, Isbell RF (2009) Soil profile. In ‘Australian soil and land survey field handbook’. 3rd edn. (National Committee on Soil and Terrain) pp. 147–204. (CSIRO Publishing: Melbourne)

McKenzie DC, Abbott TS, Slavich PG, Hall DJM (1993) The nature, distribution and management of sodic soils in New South Wales. Australian Journal of Soil Research 31, 839–868.
The nature, distribution and management of sodic soils in New South Wales.Crossref | GoogleScholarGoogle Scholar |

McKyes E, Nyamugafata P, Nyamapfene KW (1994) Characterization of cohesion, friction and sensitivity of two hardsetting soils from Zimbabwe. Soil & Tillage Research 29, 357–366.
Characterization of cohesion, friction and sensitivity of two hardsetting soils from Zimbabwe.Crossref | GoogleScholarGoogle Scholar |

Mead JA, Chan KY (1988) Effect of deep tillage and seedbed preparation on the growth and yield of wheat on a hard-setting soil. Australian Journal of Experimental Agriculture 28, 491–498.
Effect of deep tillage and seedbed preparation on the growth and yield of wheat on a hard-setting soil.Crossref | GoogleScholarGoogle Scholar |

Mead JA, Chan KY (1992) Cultivation techniques and grazing affect surface structure of an Australian hardsetting soil. Soil & Tillage Research 25, 217–230.
Cultivation techniques and grazing affect surface structure of an Australian hardsetting soil.Crossref | GoogleScholarGoogle Scholar |

Moura EG, Moura NG, Marques ES, Pinheiro KM, Costa Sobrinho JRS, Aguiar ACF (2009) Evaluating chemical and physical quality indicators for a structurally fragile tropical soil. Soil Use and Management 25, 368–375.
Evaluating chemical and physical quality indicators for a structurally fragile tropical soil.Crossref | GoogleScholarGoogle Scholar |

Mullins CE (1997) Hardsetting. In ‘Methods for assessment of soil degradation’. (Eds R Lal, WH Blum, C Valentin, BA Stewart) pp. 109–128. (CRC Press Inc.: Boca Raton, FL)

Mullins CE, Ley GJ (1995) Mechanisms and characterisation of hardsetting in soils. In ‘Proceedings of 2nd International Symposium on Sealing, Crusting and Hardsetting Soils: Productivity and Conservation’. (Eds HB So, GD Smith, SR Raine, BM Schaffer, RJ Loch) pp. 157–170. (Australian Society of Soil Science Inc., Queensland Branch: Brisbane)

Mullins CE, MacLeod DA, Northcote KH, Tisdall JM, Young IM (1990) Hardsetting soils: behaviour, occurrence and management. In ‘Soil degradation’. Advances in Soil Science No. 11. (Eds R Lal, BA Stewart) pp. 37–108. (Springer-Verlag: New York)

Murphy BW, Koen TB, Jones BA, Huxedurp LM (1993) Temporal variation of hydraulic properties for some soils with fragile structure. Australian Journal of Soil Research 31, 179–197.
Temporal variation of hydraulic properties for some soils with fragile structure.Crossref | GoogleScholarGoogle Scholar |

Naidu R, Merry RH, Churchman GJ, Wright MJ, Murray RS, Fitzpatrick RW, Zarcinas BA (1993) Sodicity in South Australia – a review. Australian Journal of Soil Research 31, 911–929.
Sodicity in South Australia – a review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXksFKnsb8%3D&md5=79c9418c04161737f032ece815ae2930CAS |

Northcote KH (1979) ‘A factual key for the recognition of Australian soils.’ 4th edn (Rellim Technical Publications: Glenside, S. Aust.)

Northwood PJ, Macartney JC (1971) The effect of different amounts of cultivation on the growth of maize on some soil types in Tanzania. Tropical Agriculture 48, 25–33.

Or D (1996) Wetting-induced soil structural changes: The theory of liquid phase sintering. Water Resources Research 32, 3041–3049.
Wetting-induced soil structural changes: The theory of liquid phase sintering.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XmsFOqs7c%3D&md5=17d854c0aab7860171d862cf90834f16CAS |

Osberg DC, Doube BM, Hanrahan SA (1993) Habitat specificity in African dung beetles: the effect of soil type on dung burial by two species of ball-rolling dung beetles (Coleoptera Scarabaeidae). Tropical Zoology 6, 243–251.

Packer IJ, Hamilton GJ (1993) Soil physical and chemical changes due to tillage and their implications for erosion and productivity. Soil & Tillage Research 27, 327–339.
Soil physical and chemical changes due to tillage and their implications for erosion and productivity.Crossref | GoogleScholarGoogle Scholar |

Proffitt APB, Bendotti S, McGarry D (1995a) A comparison between continuous and controlled grazing on a red duplex soil. I. Effects on soil physical characteristics. Soil & Tillage Research 35, 199–210.
A comparison between continuous and controlled grazing on a red duplex soil. I. Effects on soil physical characteristics.Crossref | GoogleScholarGoogle Scholar |

Proffitt APB, Bendotti S, Riethmuilerb GP (1995b) A comparison between continuous and controlled grazing on a red duplex soil. II. Subsequent effects on seedbed conditions, crop establishment and growth. Soil & Tillage Research 35, 211–225.
A comparison between continuous and controlled grazing on a red duplex soil. II. Subsequent effects on seedbed conditions, crop establishment and growth.Crossref | GoogleScholarGoogle Scholar |

Rengasamy P, Greene RSB, Ford GW, Mehanni AH (1984) Identification of dispersive behaviour and the management of red-brown earths. Australian Journal of Soil Research 22, 413–431.
Identification of dispersive behaviour and the management of red-brown earths.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2MXitlCrtA%3D%3D&md5=2049da4e795dbaef7fd70b21eaec8ff0CAS |

Richards LA (1953) Modulus of rupture as an index of crusting of soil. Soil Science Society of America Proceedings 17, 321–323.
Modulus of rupture as an index of crusting of soil.Crossref | GoogleScholarGoogle Scholar |

Smith GD, Coughlan KJ, Yule DF, Laryea KB, Srivastava KL, Thomas NP, Cogle AL (1992) Soil management options to reduce runoff and erosion on a hardsetting Alfisol in the semi-arid tropics. Soil & Tillage Research 25, 195–215.
Soil management options to reduce runoff and erosion on a hardsetting Alfisol in the semi-arid tropics.Crossref | GoogleScholarGoogle Scholar |

So B, Aylmore LAG (1993) How do sodic soils behave? The effects of sodicity on soil physical behaviour. Australian Journal of Soil Research 31, 761–777.
How do sodic soils behave? The effects of sodicity on soil physical behaviour.Crossref | GoogleScholarGoogle Scholar |

So HB, Smith GD, Raine SR, Schaffer BM, Loch RJ (Eds) (1995) ‘Proceedings of 2nd International Symposium on Sealing, Crusting and Hardsetting Soils, Productivity and Conservation’. (Australian Society of Soil Science Inc., Queensland Branch: Brisbane)

So HB, Grabski A, Desborough P (2009) The impact of 14 years of conventional and no-till cultivation on the physical properties and crop yields of a loam soil at Grafton NSW, Australia. Soil & Tillage Research 104, 180–184.
The impact of 14 years of conventional and no-till cultivation on the physical properties and crop yields of a loam soil at Grafton NSW, Australia.Crossref | GoogleScholarGoogle Scholar |

Stenberg M, Hakansson I, Polgar von J, Heinonen R (1995) Sealing, crusting and hardsetting soils in Sweden — occurrence, problems and research. In ‘Proceedings of 2nd International Symposium on Sealing, Crusting and Hardsetting Soils: Productivity and Conservation’. (Eds HB So, GD Smith, SR Raine, BM Schaffer, RJ Loch) pp. 287–292. (Australian Society of Soil Science Inc., Queensland Branch: Brisbane)

Stirzaker RJ, Passioura JB, Sutton BG, Collis-George N (1993) Soil management for irrigated vegetable production. II. Possible causes for slow vegetative growth of lettuce associated with zero tillage. Australian Journal of Agricultural Research 44, 831–844.
Soil management for irrigated vegetable production. II. Possible causes for slow vegetative growth of lettuce associated with zero tillage.Crossref | GoogleScholarGoogle Scholar |

Stock O, Downes NK (2008) Effects of additions of organic matter on the penetration resistance of glacial till for the entire water tension range. Soil & Tillage Research 99, 191–201.
Effects of additions of organic matter on the penetration resistance of glacial till for the entire water tension range.Crossref | GoogleScholarGoogle Scholar |

Sumner ME (1993) Sodic soils: new perspectives. Australian Journal of Soil Research 31, 683–750.
Sodic soils: new perspectives.Crossref | GoogleScholarGoogle Scholar |

Taboada MA, Lavado RS (1996) Interactive effects of exchangeable sodium and water content on soil modulus of rupture. Soil Technology 8, 345–349.
Interactive effects of exchangeable sodium and water content on soil modulus of rupture.Crossref | GoogleScholarGoogle Scholar |

Tisdall JM, Adem HH (1988) An example of custom prescribed tillage in South-eastern Australia. Journal of Agricultural Engineering Research 40, 23–32.
An example of custom prescribed tillage in South-eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Townend J, Mtakwa PW, Mullins CE, Simmonds LP (1996) Soil physical factors limiting establishment of sorghum and cowpea in two contrasting soil types in the semi-arid tropics. Soil & Tillage Research 40, 89–106.

Utomo WH, Dexter AR (1981) Soil friability. Journal of Soil Science 32, 203–213.
Soil friability.Crossref | GoogleScholarGoogle Scholar |

Valentin C, Bresson LM (1992) Morphology, genesis and classification of surface crusts in loamy and sandy soil. Geoderma 55, 225–245.
Morphology, genesis and classification of surface crusts in loamy and sandy soil.Crossref | GoogleScholarGoogle Scholar |

Weaich K, Cass A, Bristow KL (1992) Use of a penetration resistance characteristic to predict soil strength development during drying. Soil & Tillage Research 25, 149–166.
Use of a penetration resistance characteristic to predict soil strength development during drying.Crossref | GoogleScholarGoogle Scholar |

Wheaton AD, McKenzie BM, Tisdall JM (2008) Management to increase the depth of soft soil improves soil conditions and grapevine performance in an irrigated vineyard. Soil & Tillage Research 98, 68–80.
Management to increase the depth of soft soil improves soil conditions and grapevine performance in an irrigated vineyard.Crossref | GoogleScholarGoogle Scholar |

Willcocks TJ (1980) Tillage of clod-forming sandy loam soils in the semiarid climate of Botswana. Soil & Tillage Research 1, 323–350.
Tillage of clod-forming sandy loam soils in the semiarid climate of Botswana.Crossref | GoogleScholarGoogle Scholar |

Willcocks TJ (1984) Tillage requirements in relation to soil type in semiarid rainfed agriculture. Journal of Agricultural Engineering Research 30, 327–336.
Tillage requirements in relation to soil type in semiarid rainfed agriculture.Crossref | GoogleScholarGoogle Scholar |

Willis TM, Hall DJM, McKenzie DC, Barchia I (1999) Erratum to ‘Soybean yield as affected by crop rotations, deep tillage and irrigation layout on a hardsetting Alfisol’. Soil & Tillage Research 49, 347–356.
Erratum to ‘Soybean yield as affected by crop rotations, deep tillage and irrigation layout on a hardsetting Alfisol’.Crossref | GoogleScholarGoogle Scholar |

Young IM (1992) Hardsetting soils in the UK. Soil & Tillage Research 25, 187–193.
Hardsetting soils in the UK.Crossref | GoogleScholarGoogle Scholar |

Young IM, Mullins CE (1991) Water-suspensible solids and structural stability. Soil & Tillage Research 19, 89–94.
Water-suspensible solids and structural stability.Crossref | GoogleScholarGoogle Scholar |

Zaher H, Caron J (2008) Aggregate slaking during rapid wetting: Hydrophobicity and pore occlusion. Canadian Journal of Soil Science 88, 85–97.
Aggregate slaking during rapid wetting: Hydrophobicity and pore occlusion.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXksVemu7k%3D&md5=842ed6308edb886cd4bbb29e49982f41CAS |