**5. Crop management and production**

The recommended sowing time is between the 1st and 20th of September. The soil must be prepared similarly to any other cereals (e.g. wheat, barley etc). The seeds should be sown at the depth of 2-2.5 cm with the sowing distance of 12-15 cm. The seed quantity for a hectare land is approx. 40 kg. The seedlings emerge in 14-18 days. Weed management is necessary in this phase of the development of energy grass plantations to avoid the weed species strengthening at the expense of energy grass individuals. In the early spring rolling on the plantation can be important to mitigate the negative effects of winter frost on the root

Tall Wheatgrass Cultivar Szarvasi–1 (*Elymus elongatus* subsp. *ponticus* cv. Szarvasi–1)

content but an extremely low total biomass yield.

depends mainly on the soil types.

**Biomass yields t/ha**

Hungary)

as a Potential Energy Crop for Semi-Arid Lands of Eastern Europe 283

Mollisol, likely due to the better water availability, can be seen in Fig. 12. as a relatively high difference between the weight of the fresh and the dry matter. The lowest yield was measured on the Alfisol experimental site. Here, both the water and the nutrient supply was under the control of the high clay content of the soil which resulted in a relatively high dry matter

Temporal variability of biomass production of energy grass Szarvasi-1 was also studied in a three-year-long field experiment (2004-2007) in the South Transdanubian region (Hungary). According to our results, the main source of variability was the amount of precipitation. Particularly on the sites with low water table, biomass production decreased with up to 50 % of the average biomass quantity in the year of extreme low precipitation. We measured 6 tons of dry matter per a hectare in 2007 instead of 12 tons of dry biomass yield in a better year (2006). Phenotypic plasticity of Szarvasi-1 energy grass cultivations can therefore be regarded as not very high, resulting in considerable variability of biomass yields in different years. An extended fertilization experiment was conducted in two different environments in terms of climate and soil types in south-eastern and in south-western Hungary at a distance of 250 km from each other, in order to find the optimal nutrient supply of Szarvasi-1 energy grass crop (Fig. 13.). As our results suggested, the demand of energy grass for fertilization

Alfisol-Mollisol Alfisol Aquic Mollisol

Fresh w eight Dry w eight

Fig. 12. Biomass yields in 2006 on three study sites near Bóly on different soil types (South

system. The first cut can be made in the Central European climate at the beginning of July when the plantation is in full flower. The later the cut takes place the lower the water content is in the biomass as it is shown in Fig. 11. The water content of the biomass is highest in fresh plant material in spring (approx. 80 %), but during the process of ripening it decreases to 50 % resulting in a higher dry material ratio. Although the highest biomass weight for a unit area can be measured in late spring, the highest dry material weight can be achieved just in the late summer when the seeds are already ripe. The fresh biomass weight reaches its peak with the appearance of the inflorescence, however the high water content decreases its value as solid biofuel. In early August when seeds are ripening plant biomass has a moderately smaller fresh weight but with the highest dry material content. Thereafter, during the autumn (this is not depicted in the figure), dry biomass weight decreases more intensively than water content indicating some loss in dry material content, too.

Fig. 11. Changes in fresh and dry weight of yields during a growing season on solonec meadow soil type (mean and SD)

Three or 5 days of full sunshine can reduce the water content of Szarvasi-1 energy grass hay to 9-12 % when it is ready to be baled. In this dry condition the bales can be stored for a long time without a chance of rotting. Later, during the autumn a second mow can be made in October resulting in a lower quantity of biomass with higher content of protein content. The second harvest can be used as forage for cattle or can be grazed in situ.

Soil type has a considerable effect on biomass yields. In the same macroclimatic condition the average weight of the harvested biomass for a unit land can be as much as two times higher thanks to different water and nutrient availability as well as physical soil properties such as texture and compactness of the used soil. An example of this is shown in Fig. 12.

Three soil types were chosen to represent the effect of soil on the yields of energy grass plantations. Alfisol, Alfisol-Mollisol and Aquic Mollisol comprise about 50 % of the cropfields of the South Transdanubian region in South Hungary. The highest yield in fresh as well as dry matter was achieved on Alfisol-Mollisol soil that contained moderate clay fraction and hence it bears a well balanced water and nutrient household. The Aquic Mollisol site was under the control of a relatively high ground water table, particularly in the spring, hindering the early development of the plantation. On the other hand, the high ground water table could serve as a good water source later in the summer, so the overall yield became high enough similarly to that on Alfisol-Mollisol. The relatively higher water content of the biomass produced on Aquic

system. The first cut can be made in the Central European climate at the beginning of July when the plantation is in full flower. The later the cut takes place the lower the water content is in the biomass as it is shown in Fig. 11. The water content of the biomass is highest in fresh plant material in spring (approx. 80 %), but during the process of ripening it decreases to 50 % resulting in a higher dry material ratio. Although the highest biomass weight for a unit area can be measured in late spring, the highest dry material weight can be achieved just in the late summer when the seeds are already ripe. The fresh biomass weight reaches its peak with the appearance of the inflorescence, however the high water content decreases its value as solid biofuel. In early August when seeds are ripening plant biomass has a moderately smaller fresh weight but with the highest dry material content. Thereafter, during the autumn (this is not depicted in the figure), dry biomass weight decreases more

intensively than water content indicating some loss in dry material content, too.

yields (t/ha)

meadow soil type (mean and SD)

fresh weight

dry material weight

fresh weight

inflorescent

Fig. 11. Changes in fresh and dry weight of yields during a growing season on solonec

shooting appearance of

second harvest can be used as forage for cattle or can be grazed in situ.

dry material weight

fresh weight

**Harvesting in different phenophases**

Three or 5 days of full sunshine can reduce the water content of Szarvasi-1 energy grass hay to 9-12 % when it is ready to be baled. In this dry condition the bales can be stored for a long time without a chance of rotting. Later, during the autumn a second mow can be made in October resulting in a lower quantity of biomass with higher content of protein content. The

Soil type has a considerable effect on biomass yields. In the same macroclimatic condition the average weight of the harvested biomass for a unit land can be as much as two times higher thanks to different water and nutrient availability as well as physical soil properties such as texture and compactness of the used soil. An example of this is shown in Fig. 12. Three soil types were chosen to represent the effect of soil on the yields of energy grass plantations. Alfisol, Alfisol-Mollisol and Aquic Mollisol comprise about 50 % of the cropfields of the South Transdanubian region in South Hungary. The highest yield in fresh as well as dry matter was achieved on Alfisol-Mollisol soil that contained moderate clay fraction and hence it bears a well balanced water and nutrient household. The Aquic Mollisol site was under the control of a relatively high ground water table, particularly in the spring, hindering the early development of the plantation. On the other hand, the high ground water table could serve as a good water source later in the summer, so the overall yield became high enough similarly to that on Alfisol-Mollisol. The relatively higher water content of the biomass produced on Aquic

dry material weight

fresh weight

flowering ripe seeds

dry material weight

Mollisol, likely due to the better water availability, can be seen in Fig. 12. as a relatively high difference between the weight of the fresh and the dry matter. The lowest yield was measured on the Alfisol experimental site. Here, both the water and the nutrient supply was under the control of the high clay content of the soil which resulted in a relatively high dry matter content but an extremely low total biomass yield.

Temporal variability of biomass production of energy grass Szarvasi-1 was also studied in a three-year-long field experiment (2004-2007) in the South Transdanubian region (Hungary). According to our results, the main source of variability was the amount of precipitation. Particularly on the sites with low water table, biomass production decreased with up to 50 % of the average biomass quantity in the year of extreme low precipitation. We measured 6 tons of dry matter per a hectare in 2007 instead of 12 tons of dry biomass yield in a better year (2006). Phenotypic plasticity of Szarvasi-1 energy grass cultivations can therefore be regarded as not very high, resulting in considerable variability of biomass yields in different years.

An extended fertilization experiment was conducted in two different environments in terms of climate and soil types in south-eastern and in south-western Hungary at a distance of 250 km from each other, in order to find the optimal nutrient supply of Szarvasi-1 energy grass crop (Fig. 13.). As our results suggested, the demand of energy grass for fertilization depends mainly on the soil types.

Fig. 12. Biomass yields in 2006 on three study sites near Bóly on different soil types (South Hungary)

Tall Wheatgrass Cultivar Szarvasi–1 (*Elymus elongatus* subsp. *ponticus* cv. Szarvasi–1)

cultivation against conventional arable crops.

**6.1.1 Weed composition of Szarvasi-1 fields** 

this topic was published by Pál & Csete (2008).

similar species composition to this perennial crop.

**6. Plant protection** 

**6.1 Weeds** 

as a Potential Energy Crop for Semi-Arid Lands of Eastern Europe 285

yield substantially. Too high water table can prevent the energy grass crop forming closed and well established stands, while too low water table (less then 4 m in depth) can limit biomass production during the dry season in summer. As a consequence, the optimal water table level is estimated to be between 1 and 3 meters in depth in the course of the whole growing period. In conclusion, we can claim that depending on the soil type, nutrient availability and precipitation, Szarvasi-1 energy grass crop can produce 10-25 dry matter/ha biomass a year, but this value cannot reach 5 tons in the case of soils with a high clay content and low precipitation. One harvest in the middle of August can achieve these biomass yields while in the rest of the year an additional 30-40 cm high second growth can be obtained. Beneficial choice of location for the establishment of Szarvasi-1 energy grass fields can result in considerably higher biomass yields increasing the competitive ability of this new biomass

Knowledge of weed assemblies is extremely important for an effective weed management in all arable cultures. Therefore introducing new crops to large scale cultivation requires comprehensive preliminary investigations. In this chapter the characteristic species composition as well as abundances of weeds on Szarvasi-1 energy grass fields were determined and were compared to other arable crop cultures. Weed-crop competition was also studied in different soil conditions. The analyses were made on the basis of 22 energy grass, 60 cereal, 60 row crop and 15 alfalfa plots that were 4x4 m in size. A detailed study on

**6.1.2 Relation of weed species composition in energy grass to other arable cultures**  Comparing the weed composition of energy grass fields to other cultures on landscape and field level in terms of an ordination diagram showed a distinctive separation from cereals and row crops (Fig. 15.). A partial overlapping was detected with alfalfa fields, suggesting a

Fig. 15. Scatter diagram of the weed composition of different crops (eg = energy grass,

a = alfalfa, rc = row crops, c = cereals) (PCoA, Jaccard similarity index)

Fig. 13. Experimental fields near Szarvas (Southeast Hungary) to find optimal fertilizer management type (photo: Róbert W. Pál)

The response of biomass production to nitrogen is relatively high, already 60 kg N/ha can double the dry biomass matter as can be seen in Fig. 14. Until this dose, increasing amounts of nitrogen contribute to increasing biomass production in a linear relationship. Higher doses than 60 kg/ha nitrogen by itself does not increase the biomass production further due to the lack of other major nutrients, such as potassium and phosphorus. Adding these to the experiment in different doses we have found that biomass production can be increased a further 50 % until it reaches 13 tons dry matter per hectare. The best ratio of the three major nutrients was shown to be 1:1:1 or 3:2:2 to maximize biomass yield of energy grass.

Fig. 14. Biomass yields from fertilizer study near Szarvas (solonec meadow soil)

Nitrogen played an important role in biomass production increasing biomass weight in any phenophases, while potassium and phosphorus were shown to be important only in the early phenophases (spring and flowering period and the beginning of the flowering time, respectively).

The maximum dry matter production of Szarvasi-1 energy grass crop was shown to be dependent on soil types and water supply. In our experiments 13 tons per hectare dry matter derived from solonec meadow soil, while in better soil conditions we got 20-25 tons dry matter per hectare. High and low levels of the average groundwater table can also decrease biomass yield substantially. Too high water table can prevent the energy grass crop forming closed and well established stands, while too low water table (less then 4 m in depth) can limit biomass production during the dry season in summer. As a consequence, the optimal water table level is estimated to be between 1 and 3 meters in depth in the course of the whole growing period.

In conclusion, we can claim that depending on the soil type, nutrient availability and precipitation, Szarvasi-1 energy grass crop can produce 10-25 dry matter/ha biomass a year, but this value cannot reach 5 tons in the case of soils with a high clay content and low precipitation. One harvest in the middle of August can achieve these biomass yields while in the rest of the year an additional 30-40 cm high second growth can be obtained. Beneficial choice of location for the establishment of Szarvasi-1 energy grass fields can result in considerably higher biomass yields increasing the competitive ability of this new biomass cultivation against conventional arable crops.
