The effect of decomposing biomass of the grasses Festuca arundinacea, F. ovina, and F. rubra on the species composition and quality of lawns

The aim of the study was to assess the impact of cut vegetative shoots of chosen lawn grass cultivars of Festuca being left on the lawn sward surface on the species composition, sodding and appearance, and over-wintering of the lawn. The influence of decomposing biomass was studied in a field experiment between 2008 and 2014. Each cultivar was sown as a monoculture on microplots with an area of 1 m2. The control consisted of sites from which the cut sward had been removed immediately after cutting.The results obtained may indicate an allelopathic effect of the cut sward of the cultivars left on the lawn surfaces. The following had the most negative effects on the species composition of the lawn sward (from greater to lesser negative impact): F. ovina ‘Espro’, F. rubra ‘Areta’, F. arundinacea ‘Asterix’, and F. ovina ‘Pintor’. With the exception of ‘Espro’, these cultivars also limited the presence of dicotyledonous plants in the lawn sward. The cover of dicotyledonous plants and other unsown grasses was also recorded on the sites with F. rubra ‘Olivia’ and ‘Nimba’. The greatest negative influence on the sodding of the lawn swards was demonstrated by the latter F. rubra cultivar, whereas F. ovina ‘Espro’ had the greatest negative influence on the appearance. However, no differences were found in assessments of over-wintering of the cultivars at the study sites. However, taking into account the scale of these impacts on the characteristics evaluated, the cultivars of Festuca species tested can be recommended for extensive use, where a cut sward can be left on the surface of the lawn. Some caution in this respect is recommended when it comes to F. ovina ‘Espro’ and F. rubra ‘Areta’ and ‘Nimba’.