Hoosfield Barley

Hoosfield Crop Nutrient Content

The Hoosfield experiment was started in 1852 to investigate the relative importance of the plant nutrients nitrogen, phosphorus, potassium, magnesium and sodium (N, P, K, Mg and Na) and silicate (Si), applied as either fertilizer or manures, on the yield of spring barley. From the start of the experiment, samples of barley grain and straw were kept for chemical analysis, although straw samples from the 19th Century are limited.

Early analysis

Lawes and Gilbert (1857) reported on yield and %N for the first six years of the experiment, and Gilbert (1893) on yield and grain composition for the first 30 years.

Hall and Morrison (1906) and Fisher (1929) reported on the effects of silica on yield.

Russell and Watson (1939) comprehensively discuss the effects of the different plant nutrients and FYM on composition and quality of barley grain from 1852-1937. Yates and Watson (1939) also published data on crop N content.

Warren and Johnston (1967) compared N, P, K, Ca, Mg and Na content in grain and straw of the old variety Plumage Archer and the modern variety Maris Badger, in 1964 and 1966. This data is available in the dataset HFBNUTRI. They also report on the effects of sodium silicate on P%.

The whole experiment was fallowed in 1912, 1933, 1943 and 1967.

1968 to present

In 1968 some of the Hoosfield plots (subsequently called the "Main" plots) were divided into four sub-plots, to test four rates of N. Two three-course rotations with barley, potatoes and beans were started on Series AA and C of the experiment; plots were divided into 16 sub-sub-plots to accommodate the different crops and four rates of N. The rotations continued until 1978.

No barley grain or straw was analysed for nutrient content in 1968 or 1969. From 1970 onwards grain samples were analysed for total N every year. On the Main plots straw was also analysed, and in most years, P, K, Ca, Mg, Na were also determined. Sulphur (S) concentrations in grain and straw have been determined since 1996. See Main Plot nutrient data, 1964-2000 and Main Plot nutrient data, 2001 onwards for details of which elements were measured on which plots.

Leigh and Johnston (1983, 1985 and 1986) published a series of papers looking at N, P and K in dry matter and tissue water on the Hoosfield barley crops.

15N-labelled fertilizer was applied to plots of contrasting nutrient status on Hoosfield in 1986 and 1987. The grain and straw total N and 15N content was measured over several years (Glendining et al, 1997, 2001).

Hoosfield crop nutrient data is available from e-RA as the following datasets:

• HFBNUTRI: Spring barley grain and straw nutrient data, 1964 & 1966, two contrasting varieties, all plots
• HFNUTRIMAIN: Spring barley grain and straw nutrient data, 1970 onwards.
Main Plots 111-724 (old Series O and A) 1970-2000. Plots 631-4 and 731-4 were added 2001 onwards.

See Main Plot nutrient data, 1964-2000 and Main Plot nutrient data, 2001 onwards for details of which elements were measured on which plots.

Methodology

For analytical techniques used prior to 1968 see Johnston (1969) in Methodology References below.

Nitrogen (N)

1968-1995: nitrogen content was determined by Kjeldahl digest, the digest was then analysed colorimetrically using a Technicon segmented flow analyser. If nitrate-N was expected to be high in the sample, the salicylic acid modification was used (Bremner, 1965).

1996 onwards: nitrogen content is determined by combustion analyser, based on the Dumas method. Originally a Heraeus Combustion analyser, currently a LECO combustion system is used.

Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Sodium (Na) and Sulphur (S)

1968-late 1980s: dry ashing techniques, as described by Piper (1942) were used to produce an acid extract. The extracts were analysed for P colorimetrically on a Technicon Auto Analyser, or later equivalents (Alpkem continuous flow system / Skalar SanPlus segmented flow system), using the modified Murphy & Riley (1962) molybdenum blue method developed from Fogg & Wilkinson (1958). K, Ca, Mg and Na were determined using automated atomic absorption methods. The SP90 atomic absorption flame photometer was used to analyse Ca, Mg and Na; K was analysed by the EEL flame photometer until 1973, K was then analysed with Ca, Mg and Na by the SP90. S was not routinely measured until 1996.

1980s onwards: since the late 1980s the open tube nitric-perchloric digestion (Zarcinas, et al, 1987) has been used to produce an acid extract. P, K, Ca, Mg and Na have been determined by ICP-OES (Inductively-coupled plasma - optical emission Spectrometer) since 1982, and S since 1996.

Blank (control) values: Data for sodium is presented after the analysis blanks (controls) have been subtracted from the raw data. Sodium blank values tend to be relatively large, and can be greater than the raw data. If subtracting the blank resulted in a negative value, this is shown as zero. Thus the sodium data should be treated with some caution. Blank (control) readings for the other nutrients are very small, relative to the sample values, and have not been subtracted.

Methodology References:

• Bremner, J. M. (1965). Total nitrogen. In Methods of Soil Analysis. Part 2 (ed. C. A. Black), pp. 1149-1178. Madison: American Society of Agronomy.
• Fogg, D.N. and Wilkinson, N.T. (1958). The colorimetric determination of phosphorus. Analyst, London, 83:406-414.
• Johnston, A. E. (1969) "The plant nutrients in crops grown on Broadbalk", Rothamsted Experimental Station Report for 1968, Part 2, 50-62.
• Piper, C.S. (1942) Soil and plant analysis. The University of Adelaide, Adelaide, Australia.
• Zarcinas, B.A., Cartwright, B., Spouncer, L.R., 1987. Nitric acid digestion and multi-element analysis of plant material by inductively coupled plasma spectrometry. Communications in Soil Science and Plant Analysis 18:131-146.

Key References

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