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VI/1/2015
INTERDISCIPLINARIA ARCHAEOLOGICA
NATURAL SCIENCES IN ARCHAEOLOGY
homepage: http://www.iansa.eu
Yield and Nutritive Value of Grain, Glumes and Straw of
Triticum dicoccum
Produced by Prehistoric Technology in Comparison to
T. aestivum
Produced
by Modern Technology
Michal Hejcman
a,b*
, Pavla Hejcmanová
c
a
Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Kamýcká 1176, CZ-165 21 Prague 6 – Suchdol, Czech Republic
b
Department of Archaeology, Faculty of Arts, University of Hradec Králové, Rokitanského 62, CZ-500 03 Hradec Králové, Czech Republic
c
Faculty of Tropical AgriSciences, Czech University of Life Sciences, Kamýcká 129, Prague 6 – Suchdol, 16521, Czech Republic
1. Introduction
Triticum dicoccum
(emmer wheat) was the most important
cereal species planted by the frst European farmers,
followed by
T. monococcum
(Tempír 1976; van Zeist
et al.
1991; Issac
et al.
2010; Kočár, Dreslerová 2010).
In archaeological records from the Czech Republic and
Germany, the dominance of
T. dicoccum
lasted for at least
6,000 years, from the LBK (Linear Pottery culture, 5,500–
4,900 B.C.) of the Neolithic to the Migration period (A.D.
400–580, Kreuz
et al.
2005; Jacomet 2009; Dreslerová,
Kočár 2013). In the Czech Republic, cultivation of
T.
dicoccum
probably prevailed in lowlands with high-quality
soils, whereas cultivation of
Hordeum vulgare
was more
common at higher altitudes in the Late Bronze and Early
Iron ages (Dreslerová
et al.
2013).
In the Mediterranean region,
T. dicoccum
had been
frequently planted up to the High Middle Ages and then
only sporadically in low productive and dry regions (Cubero
Corpas
et al.
2008; Pena-Chocarro, Zapata 2013). In central
Volume VI ● Issue 1/2015 ● Pages 31–45
*Corresponding author. E-mail: hejcman@fzp.czu.cz
ARTICLE INFO
Article history:
Received: 19
th
January 2015
Accepted: 30
th
August 2015
Keywords:
baker wheat
emmer
harvest index
phosphorus
scratch plough
weedy species
zinc
ABSTRACT
Triticum dicoccum
(emmer) was the main crop from the start of the Neolithic period up to the migra-
tion period in central Europe, but almost nothing is known about its planting and nutritive value under
prehistoric conditions. To fll this gap, we performed an archaeological experiment aimed at comparing
the soil properties, grain and straw yields, hulled and harvest index, nutritive values of grain, glume
and straw, plant height, and weedy communities, in stands of
T. dicoccum
established on an old feld
used for crop production for several preceding years, and a stand of
T. dicoccum
established on a
feld converted from permanent grassland by hoe-digging. To demonstrate differences between old and
modern technologies and cereals, the obtained data were compared with those for a modern variety of
T. aestivum
planted on a modern feld. Key results and conclusions: (1) digging using a hoe was the
easiest way to convert permanent grassland into arable feld. The use of a scratch plough or wooden
spade for soil preparation was effective only on the permanent arable feld without dense grass swards.
(2) Broadcast seeding was a simple and effective method for the establishment of
T. diccocum
stands.
Spikelets that remained on the soil surface after seeding were eaten by rodents and birds. (3)
Triticum
dicoccum
possessed a high grain-yield compensation ability, a high competitive ability to cope with
weeds, and a high value for its grain, particularly with respect to human N, P, Mg, Fe, Cu and Zn nutri-
tion. (4) In prehistory, no strict borders between arable felds and grasslands probably existed, as many
grassland species were also weeds on arable land, such as
Plantago lanceolata
and
Trifolium repens
.
(5) The grain yield of
T. dicoccum
of 1.7–1.8 t ha
–1
probably corresponds to the yields of prehistoric
farmers on high-quality soils in central Europe. The grain yield of a modern variety of
T. aestivum
was
4.7 t ha
–1
. (6) The nutritive value of glumes was low in comparison to that of grain. We suppose that
prehistoric people preferred food made from clean grain. (7) Grain yield represented 75% of spikelet
yield. (8) The nutritive value of
T. dicoccum
and
T. aestivum
straw was insuffcient for optimum cattle
nutrition, especially due to too low N and P concentrations, together with too high fbre and lignin
contents. We conclude that straw was used for livestock feeding only if better forage was not available.
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IANSA 2015 ● VI/1 ● 31–45
Michal Hejcman, Pavla Hejcmanová: Yield and Nutritive Value of Grain, Glumes and Straw of Triticum dicoccum Produced by Prehistoric Technology in Comparison to
T. aestivum Produced by Modern Technology
32
Europe
T. dicoccum
was a marginal crop during the Middle
and New Ages and its planting survived only in low
productive and isolated regions up to the twentieth century.
The last traditional planting of
T. dicoccum
was recorded
in the mountain regions of Slovakia in the second half of
the twentieth century (Tempír 1976; Hajnalová, Dreslerová
2010).
Although
T. dicoccum
was one of the most important
crops in European Prehistory, almost nothing is known
about the nutritive value of its grain, glumes and straw under
the conditions produced by prehistoric technology. While
some archaeological experiments with the planting of
T.
dicoccum
using medieval and prehistoric technologies have
been performed, the results of such experiments have usually
been restricted to only publication of grain yields (Reynolds
1992; Cubero Corpas
et al.
2008; Ehrmann
et al.
2014). It
is supposed that straw could have been used for the winter
feeding of livestock, but the forage quality of
T. dicoccum
straw, and the possible consequences for its use in livestock
feeding in prehistory has not, according to the literature,
been evaluated. Recently,
T. dicoccum
has been investigated
as an alternative forage crop harvested as green fodder in
dry Mediterranean regions with a shortage of high-quality
forage (Cazzato
et al.
2013).
Triticum dicoccum
is a hulled
(glume) wheat, and post-harvest processing (dehusking) is
necessary to obtain clean grain without glumes (Hillman
1984; Peña-Chocarro, Zapata 2003). Did prehistoric people
consume clean grain or grain with glumes? To answer this
question, a comparison of the nutritive value of glumes and
grains is necessary, because the consumption of grain with
glumes can affect the nutritional value of the food produced.
According to our information, the analysis of the nutritive
value of glumes has never been performed, even for
T.
dicoccum
planted using modern technology. The nutritive
value of plant biomass for human and livestock nutrition
can be assessed according to the content of macro- (N, P,
K, Ca and Mg), micro- (Fe, Zn, Cu and Mn) and risk (Cd,
Pb) elements (Hejcman
et al.
2010). In addition, the forage
quality of livestock fodder can be evaluated according to
neutro (NDF) and acid (ADF) detergent fbre and by lignin
(ADL) content, which determines the digestibility of organic
matter (Hejcmanová
et al.
2014).
Broadcast seeding was probably the most frequently used
seeding technique in Prehistory, particularly under plough
agriculture (Bogaard 2004). According to Reynolds (1992),
losses of caryopses, which are normally eaten by birds and
rodents from the soil surface, can reach up to 75% using this
technique.
Many current agronomists
consider
T. dicoccum
to be
prehistoric and therefore, an old-fashioned crop; hence,
T.
dicoccum
has not been subjected to intensive modern breeding
in contrast to
T. aestivum
(Zaharieva
et al.
2010; Konvalina
et al.
2013). Contemporary landraces can therefore be used
in archaeological experiments, as their yield potential is
considered to be similar to that of landraces in prehistory. In
recent years,
T. dicoccum
has been investigated in particular
as an alternative low-yielding cereal that is suitable for
marginal areas and organic farming due to its high resistance
against disease, low N and water requirement, and a high
competitive ability against weeds in comparison to
T.
aestivum
(Marino
et al.
2009; 2011; Konvalina
et al.
2012a;
2012b). In addition, the grain of
T. dicoccum
is characterised
by higher concentrations of N, Fe and Zn in comparison to
T. aestivum
; thus
T. dicoccum
can be used to alleviate human
Zn and Fe defciency (Suchowilska
et al.
2012).
Taking into account the insuffcient information on the
nutritive value of
T. dicoccum
when planted under prehistoric
technology, we decided to perform an experiment. We
have selected a region in the northern part of the Czech
Republic on chernozem soil, where
T. dicoccum
has been
cultivated from the Neolithic to the Migration period
(Tempír 1982). The experiment was performed in the open-
air archaeological museum of Březno near Louny and its
scientifc aim was to compare soil properties, grain and straw
yields, hulled index, nutritive values of grain, glumes and
straw, harvest index, plant height. and weedy communities,
in stands of
T. dicoccum
established on an old and a new
feld. The old feld was a plot that had been used for crop
production for several preceding years (hereafter referred to
as “the old feld”). The new feld was a stand of
T. dicoccum
established on a feld converted from permanent grassland
by hoe-digging directly before seeding (hereafter referred to
as “the new feld”). To demonstrate differences between old
and modern technologies and cereals, the data obtained from
the experiment with
T. dicoccum
were compared with those
of a modern variety of
T. aestivum
planted using modern
technology in the neighbourhood of the archaeological
experiment (hereafter referred to as “the modern feld”). The
obtained results are discussed with respect to prehistoric
agricultural practices.
2. Materials and methods
2.1 Study site
The experiment was established at the open-air museum
of Březno near Louny in the NW of the Czech Republic
(50°21'34.560"N, 13°44'43.621"E). The museum was
established on the right bank of the Ohře (Eger) river in an
area of large-scale archaeological excavations performed
from the 1950s to the 1970s (Pleinerová, Pavlů 1979;
Pleinerová 2000). The area surrounding the museum was
densely inhabited from the Neolithic up to the Slavic period
(the ninth century A.D.). The altitude of the study site is
190 m asl, the mean annual temperature is 9°C, and mean
annual precipitation is 470 mm. The area is well known for
its highly fertile chernozem soils suitable for the production
of high-quality baker’s wheat. Weather conditions in the year
of planting were favourable for cereal production as there
was enough precipitation in the spring.
2.2 Field experiment
We established four 2×2 m experimental plots on the “old
feld”, which had been used for the growing of crops in the
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IANSA 2015 ● VI/1 ● 31–45
Michal Hejcman, Pavla Hejcmanová: Yield and Nutritive Value of Grain, Glumes and Straw of Triticum dicoccum Produced by Prehistoric Technology in Comparison to
T. aestivum Produced by Modern Technology
33
museum for at least ten years before the establishment of our
own experiment. The soil was prepared on the day of sowing
using a scratch plough (Figure 1a). The depth of ploughing
was up to 10 cm. In the close vicinity, another four, 2×2 m
plots as a “new feld” were established. They were converted
from permanent grassland by the use of a medieval iron
hoe. The depth of digging was up to 10 cm (Figure 1c).
Originally, we intended to convert the grassland into arable
feld by use of a scratch plough and/or a prehistoric or early
medieval wooden spade (Figure 1c), but this was too labour-
intensive and ploughing of the grassland was impossible. The
experimental “new” and “old felds” were compared with
the “modern feld”, located at a distance of 60 m from the
experimental plots. The modern feld was prepared for seeding
by ploughing using modern machinery to a depth of 30 cm.
Broadcast seeding of
T. dicoccum
spikelets onto the new
and old felds was performed on 24
th
April 2014 (Figure 1d).
We used the variety Rudico, which is well adapted to
Czech conditions (Stehno 2007) and originates from the
collection of old landraces collected by the Crop Research
Institute, Prague-Ruzyně. The seeding rate was at the upper
recommended limit of 400 germinable caryopses per m
2
(Stehno 2007). The seeding material was harvested at the
Crop Research Institute, Prague-Ruzyně, one year before
the establishment of the experiment and the germination
of caryopses was 97%. After seeding, the spikelets were
harrowed into the soil using iron/wooden rakes. In the
modern feld, winter wheat,
T. aestivum
, was seeded in
early October 2013, in rows with an inter-row distance
of 12.5 cm. We used winter wheat for comparison as this
is the most frequently planted wheat form in the Czech
Republic under farm conditions. The seeding rate was 300
germinable caryopses per m
2
. The modern feld was under
standard conventional farm management and was fertilized
by mineral N at an application rate of 100 kg N ha
–1
and
pesticides were applied if necessary. The old and new felds
did not receive any fertilizer or pesticide application or any
mechanical weeding.