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To investigate the environmental advantages of using grass-clover binary mixtures over pure stands as winter cover crops, a serial of five field experiments (each designed as randomized complete blocks with four replicates) was carried out in eastern Slovenia. Trifolium incarnatum L. and Lolium multiflorum Lam. were sown in late summer as pure stands and binary mixtures. Pooled data calculated from all the experiments revealed that the soil mineral N in spring and accumulation of N by plants decreased with decreasing proportion of T. incarnatum in the binary mixtures, while the C:N ratio of cover crop organic matter increased. C accumulation was the highest when the seeding ratio of the binary mixture of T. incarnatum and L. multiflorum was 50:50. In the C and N environmentally sustainable management efficiency coefficients, three important traits of winter cover crops for environmental protection were given equal importance (low soil mineral N content in spring, high C accumulation in plants, and high N accumulation in plants). The coefficient was higher for binary mixtures of T. incarnatum and L. multiflorum than for pure stands of these crops, proving the complex environmental advantages of binary mixtures over pure stands.

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In the present study, we investigated the species richness and species composition in relation to light and management regime in remnants of wooded meadows within the riparian forests along the middle Drava River in Slovenia. 41 plots of still managed and, at different time periods (<5 yrs, 5-15 yrs, >15 yrs), abandoned riparian wooded meadows (RWM) were sampled. In addition to vegetation relevés, light intensity (PAR) was also measured in plots. Within the still-managed RWM, two floristically distinct types were recognized using TWINSPAN analysis: meadow-like and forest-like. Light intensity differed significantly between types. The CCA of active RWM showed a significant relation between species composition and light conditions. The number of species per relevé on active RWM was negatively correlated with light intensity -in contrast to North European wooded grasslands. This could be explained by the influence of speciesrich riparian hornbeam forests that contribute many understorey species, in contrast to naturally mesotrophic meadows. CCA of both active and abandoned RWM demonstrated that light was a good predictor of RWM species composition and that abandonment caused profound changes in floristic composition. The species turnover during succession was more pronounced in less shaded meadow-like Folia Geobot (2008) 43:431-445

Cerastium holosteoides is a short‐lived plant often found in small proportions on dry and mesotropic semi‐natural, species‐rich grassland communities. To obtain more information about its nutritive value, two experiments on Arrhenatheretum elatioris grassland were carried out to examine the effect of harvest date on in vitro organic matter digestibility (IVOMD), neutral‐detergent fibre (NDF), acid‐detergent fibre (ADF), acid‐detergent lignin (ADL), estimated net energy for lactation (NEL) and crude protein (CP) concentrations of C. holosteoides, and selection of this plant by dairy cows grazing on semi‐natural grassland. C. holosteoides starts flowering in spring and continuously develops new flowers on new branches throughout the summer. Harvests were made in relation to particular growth stages of Dactylis glomerata present in the sward: (A) tillering; (B) stem elongation; (C) ear emergence; (D) flowering; and (E) ripening. Chemical composition and nutritive value were evaluated in 1998 and 1999. With advancing maturity, IVOMD of C. holosteoides decreased from 0·771 at growth stage A to 0·485 at growth stage E. At the same time, CP concentration decreased from 153 to 69 g kg−1 dry matter (DM) and estimated NEL concentration from 6·00 to 4·07 MJ kg−1 DM. With advancing maturity, there was a significant increase in NDF, ADF and ADL concentrations. In the summer harvest season, C. holosteoides contained significantly higher NDF, ADF and ADL concentrations, lower NEL concentration and had a lower IVOMD value than in the spring. Differences between years were also found for IVOMD and for NDF, ADF, ADL and NEL concentrations. In a grazing experiment in the year 1999, at growth stage B, Simmental cows grazed an A. elatioris sward in which the main species was D. glomerata (0·092), and the proportion of C. holosteoides was 0·034. C. holosteoides was, on average, grazed by cows to the same relative extent as other species in the sward.

Pulsatilla grandis is a rare and endangered species in Central Europe. A field experiment was set up to test the effects of disturbances on its germination and survival rates after artificial seeding. Disturbances were simulated by the following treatments: burning, hoeing, and removal of vegetation. The germination percentage decreased rapidly with time, to only 2% in 2-year-old fruits. The germination rate of fresh fruits was the highest in hoed plots (29.2 ± 12.9%), followed by removedvegetation plots (21.8 ± 17.3%) and burned plots (1.8 ± 2.2%). No germination was observed in control plots. The survival rate of seedlings was monitored over the next 5 years. In the year following the treatment, all the seedlings survived in the burned plots; in the hoed and in removed-vegetation plots, survival rates were 38.5 ± 2 and 55 ± 27%, respectively. Approximately half of them were alive after 5 years. Grassland vegetation in burned quadrates recovered very quickly, whereas in other disturbed plots the numbers of species and vegetation cover were very limited in the first year, but recovered in the following two years. In-seeding was successful as a short-term solution. As a long-term solution the traditional management procedures (mowing) must include a wider area and create disturbances by opening gaps within the closed grassland sward.