Tag Archives: botanical composition

513-522 R. Aavola and J. Karelson
The dynamics of botanical composition of pure and mixed grass swards on peaty soil
Abstract |

The dynamics of botanical composition of pure and mixed grass swards on peaty soil

R. Aavola and J. Karelson

Jõgeva Plant Breeding Institute, 1 J. Aamisepa St., Jõgeva alevik, 48309, Estonia,e-mail: rene.aavola@jpbi.ee

Abstract:

Major part of forage grass varieties used for (re-)seeding Estonian grasslands is imported. Little is known about their performance is severe microclimatic conditions on peat soils as official testing takes place on mineral soils. A field trial comprising 7 pure-sown grass species (8 domestic, 11 foreign varieties) and 9 mixtures composed of local varieties was sown to drained peaty soil. The aim was to determine the sward components, which preserve there. Changes in grass sward composition were observed in 2005–2007. Among pure stands, Estonian Alopecurus pratensis variety ‘Haljas’, Phleum pratense ‘Tia’ and ‘Tika’, Bromus inermis ‘Lehis’ maintained the highest percentages (86.0–92.8) of cultivated species by the third harvest year. Only B. inermis survived a harsh winter with negligible winterkill. The frost devastated the stands of Festulolium, Festuca pratense and F. arundinacea. ‘Lehis’ turned out to be the most winter and drought resistant also in mixed grass swards. If added at a rate of 30 kg ha-1 to the mixtures with P. pratense, B. inermis effectively outcompeted the herbs (range 1.4–8.2%) by the third harvest year and became dominant (72.3–87.1%). P. pratense ‘Tia’ persisted for three years but gradually withdrew when was competing with B. inermis, and also with A. pratensis. Phalaris arundinacea was intolerant to three harvests per year at a cutting height of 7 cm and steadily declined from the swards. Dactylis glomerata and F. pratense were vulnerable to winterkill, but could partly recover at the end of a rainy season.

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11–16 Volli Geherman, Rein Viiralt and Olav Ellermäe
Comparison of leys on conventional and organic farms
Abstract |
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Comparison of leys on conventional and organic farms

Volli Geherman¹, Rein Viiralt¹ and Olav Ellermäe²

¹Department of Grassland Science and Botany, Estonian Agricultural University, Kreutzwaldi 56, 51014 Tartu, Estonia
²Department of Soil Science and Agrochemistry, Estonian Agricultural University, Viljandi Road, Tartu, Estonia

Abstract:

The objective of this research was to compare the potential production of conventional and organic leys depending on the nutritive status of the soil. Three pairs of dairy farms, located in different regions of Estonia, were selected: Lääne (west), Harju (north) and Võru (south-east) Counties. In this research work, the botanical composition of the sward,  the dry matter (DM) and crude protein (CP) yield and concentration in grass were measured. The soil pHKCl and the content of organic matter were determined, including the content of soluble plant nutrients P, K, Ca and Mg in the soil. The soil profiles were described and the soils were classified.
As the organic farms, with legume-rich swards, were quite similar to the conventional farms, the preliminary results did not show large differences between the two farming types studied. The average DM yield of the ley at the first cut and the total DM yield were higher on the conventional farms.

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