Part of experiment rhb2

Hoosfield Continuous Spring Barley Experiment soil chemical and physical properties

The Continuous Spring Barley experiment was started in 1852 on a 1.7 hectare (4.25 acre) site on Hoosfield, to test the effects of organic manure and inorganic fertilizer on the growth of spring barley. The site has probably been occupied since Roman times, and the Rothamsted map of 1623 shows the site under arable cultivation. Arable crops grown 1847-1851, before the experiment started were: turnips (with FYM and superphosphate) 1847; barley 1848; clover 1849; wheat 1850; barley (with ammonium salts) 1851.

Soil details

• FAO Classification: Chromic Luvisol (or Alisol)
• U.S. Soil Taxonomy: Aquic (or Typic) Paleudalf
• Soil Survey of England & Wales Group: Stagnogleyic paleo-argillic brown earth (Avery, 1980)
• Soil Survey of England & Wales Series: Predominately Batcombe Series (Avery and Catt, 1995).

For more details of the Batcombe and other soil series, see Cranfield University 2018 Soils Guide.

Soil texture class: Flinty silty clay loam topsoil over clay-with-flints (Avery and Catt, 1995). The soils contain a large number of flints and are slightly calcareous. Below about 2m depth the soil becomes chalk. The experiment is under-drained and the site is free draining.

Soil texture, 0-23cm (from Blake et al, 2003, plots 42 and 72)

• Sand: 28 %
• Silt: 52 %
• Clay (<2 µm): 20 %

From Avery and Catt (1995): Typical Batcombe series topsoil contains 18-27% clay, with clay content increasing with depth.

Soil pH: Since the 1950s, chalk has been applied when and where necessary to maintain a soil pH of 7.0 - 7.5. Liming stopped in 1968-1974 but started again in 1975. Since 2007 lime has been applied to most plots except the control strips and the no P strip every 5 or 6 years. Like several other old arable fields at Rothamsted, Hoosfield was given large dressings of chalk in the early part of the 19th century, when the practice was to dig out the underlying chalk and spread it on the arable land. Detailed surveys of soil pH and CaCO₃ around 1954 suggested that these early large dressings were not applied uniformly, and the amount applied lessened with increasing distance from one side or corner of the field. This meant that parts of the field became acidic earlier than others. (Warren and Johnston, 1967; Jenkinson and Johnston, 1977).

Soil movement: Warren and Johnston (1967) and also Poulton (1996) discuss the early movement of soil across plot boundaries due to cultivation both along and across the plots. As a result of soil transects carried out in the 1950s, cultivations were restricted, and wide discard areas between plots introduced in the 1960s.

Plot sizes: Plots lengths: All 12.19m, except plots in strips 6 and 7, which are 9.14m. Plot widths: All 10.52m. Currently harvested area is plot length x 2.1m width. Plot harvested area data is included with plot yield data.

Soil chemical properties

Soil chemical properties have been measured at regular intervals on Hoosfield since 1852, in topsoils (0-23cm) and subsoils. See soil measurements 1852-2013 for details of what data is available. Not all plots or soil depths have been measured every year. The following soil properties have been measured:

• %N : total soil Nitrogen %
• %SOC : soil organic Carbon %
• Olsen P : plant-available phoshorus, by extraction with a solution of 0.5M NaHCO₃, buffered at pH 8.5
• pH : soil pH in water (1:2.5 soil : solution)
• Extractable cations : extractable Ca, K, Mg and Na
• % CaCO₃ : by manometry
• soil weights : see below for more details

Soil inorganic N measurements: See Bakar et al (1994) below for estimates of nitrate leaching using Br and N-15 tracers; see also Powlson et al (1989) below for measurements of nitrate leaching from FYM and inorganic N fertilizer plots.

Denitrification measurements: See Webster and Goulding (1989) below for measurements of denitrification in autumn 1987 from Hoosfield, comparing high and low SOC plots. See also Bakar et al, (1994) below for estimates of denitrication using Br and N-15 tracers.

15N-labelled fertilizer measurements: See Glendining et al (1997; 2001) for details of the fate of 15N-labelled fertilizer applied to the Hoosfield Spring Barley experiment in 1986 and 1987.

Soil properties - Main plots, 0-23cm 2008:

^aOlsen P - P soluble in 0.5 M NaHCO₃ ^bExchangeable K extracted in ammonium acetate ^cOrganic C, determined by dichromate oxidation (Tinsley, 1950).

Soil organic carbon (SOC)

Soil organic carbon has been measured at regular intervals on Hoosfield since 1852, in topsoils (0-23cm) and subsoils. See soil measurements 1852-2013 for details of what data is available. Not all plots or soil depths have been measured every year. See long-term SOC for selected treatments under 'Datasets'.

Herbst et al (2018) (see Key References, below) measured soil carbon fractions from selected fresh and archived soil samples from 1882-2012. They measured TOC (total organic carbon), and different POM (particulate organic matter) fractions, from plot 11 (no fertilizer or manure since 1852), plot 7.1 (FYM 1852-1871), plot 7.2 (FYM since 1852) and plot 7.3 (FYM since 2001), along with fresh soils from the Highfield and Fosters ley-arable experiments.

Soil weight Mkg/ha, Main Plots

The following standard soil weights should be used for Hoosfield Continuous Spring Barley Main Plots. All weights are in 10⁶ kg/ha of oven-dry fine soil. To convert to g/cm3 divide by depth in cm (eg 23) and multiply by 10. Data prepared by A J Macdonald and P R Poulton, 2012, derived from Jenkinson and Johnston (1977). Note that plot 11 (unfertilized) on the north-east part of the experimental site has a greater soil weight than the other unfertilized plots (61 and 62) and those receiving inorganic fertilizer (eg plot 42). The unfertilized plot used in the Hoosfield SOC Open Access figure is plot 11.

Hoosfield continuous spring barley soil weights 10⁶ kg/ha, 0-23cm, Main plots

^a All other Main Plots, including FYM 1852-1871 (plot 71), NPK since 1852 (plot 42) and plots 61 and 62.

Further information and acknowledgements

With thanks to Andy Macdonald and Paul Poulton for help with compiling the information and text.

Key References