Mesotrophic Grassland Research Articles

The conservation management of mesotrophic (meadow) grassland in northern England. 1. Effects of grazing, cutting date and fertilizer on the vegetation of a traditionally managed sward

AbstractThe results are reported from an experiment on the effects of cutting date (14 June, 21 July and I September), fertilizer application (none or 80 kg ha−1 N plus 40 kg ha−1 P and K) and grazing treatments (none, autumn or autumn plus spring) on the vegetation of an upland mesotrophic grassland in Upper Teesdale. northern England, UK.Effects on plant species number and cover are reported for 4 years (1989–93) of treatment. Effects on ‘species ‐attributes’ are given for the fourth year.The cessation of grazing combined with the use of fertilizer progressively reduced species number by about 25%. Under traditional management (no fertilizer, cutting date on 21 July, autumn and spring grazing) the species number and cover remained relatively static over the 4 years.Comparison between treatments in the fourth year showed a reduction in species number under the fertilizer application, cutting date on 1 September and no‐grazing treatments. Fertilizer use together with cutting date on 1 September particularly lowered species number and cover.Analysis of variance was used to assess the effect of treatment on species that occurred frequently in the sward. A cutting date of 1 September favoured Agrostis capillaris. Alopecurus pratensis, Poa trivialis, Phleum pratense and Trisetum flavescens, The absence of grazing favoured Dactylis glomerata and Holcus lanatus. The use of fertilizer particularly favoured A. pratensis and H. lanatus. Ordination methods were used to assess the effect of treatment on the less frequent species. These were primarily associated with the treatment combination that matched ‘traditional’ management. Deviations from this ‘traditional’ regime acted separately, rather than in combination, and favoured different grass species. Traditional management was associated with ruderal, stress‐tolerant ruderal and competitive ruderal strategists and with longer seed germination times, heavier seeds, some of which needed scarifying or chilling to break dormancy, and transient seed banks that germinated in the autumn.The original sward was an Anthoxanthum odora‐turn‐Geranium sylvatirum grassland, Briza media subcommunity (MG3b). After 4 years, Festuca ovina‐Agrostis capillaris‐Galium saxatile grassland, Holcus lanatus‐Trifolium repens subcom‐munity (U4b) and Lolium perenne‐Alopecurus pratensis‐Festuca pratensis grassland (MG7c) were found in many of the fertilized and late‐cutting treatments.

Seed Shed in the Making of Hay From Mesotrophic Grassland in a Field in Northern England: Effects of Hay Cut Date, Grazing and Fertilizer in a Split-Split-Plot Experiment

1. A hay crop was cut at three different dates in 1990 from a mesotrophic (meadow) grassland in Upper Teesdale, under various fertilizer, grazing and cut date treatments in a split-split-plot field experiment. The haymaking process was simulated in the laboratory with the shed seed being collected at 24-hour intervals. The extracted seed was counted and identified to species. 2. The seed was identified from 39 species, 23 of which occurred in more than 10% of the quadrats. Seventeen species showed significant differences in the amount of seed extracted at different cut dates. The overall forb/grass seed quotient decreased from 2.92 on 14 June, to 0.82 on 21 July, to 0.15 on 3 September. 3. Grazing and fertilizer treatments significantly affected seed numbers for a few species. 4. Fifteen species showed significant (P < 0.01) declining linear trends in the amount of seed released by successive 24-hour shakes.

The Effects of Grazing Management on the Vegetation of Mesotrophic (Meadow) Grassland in Northern England

Haymeadows in the Yorkshire Dales and the North Pennines in Northern England are grazed with cattle and sheep outside the 2-3-month summer period, when a hay or silage crop is grown. Experimental exclosures were used from August 1987 to June 1991 to prevent this grazing for various periods in the year in a meadow at Ravenstonedale, Cumbria. Vegetation change was investigated using biomass samples taken in June of each year. Experimental treatments were: no grazing at any time of the year; no grazing from the time of the hay cut until 1 January; no grazing from 1 January to the time of the hay cut; control plots in which the normal grazing regime was followed each year. All other management factors were kept constant. All plots showed vegetation changes related to treatment and to time (...)

The Phenology of Mesotrophic Grassland in the Pennine Dales, Northern England: Historic Hay Cutting Dates, Vegetation Variation and Plant Species Phenologies

(1) The relevance to conservation of a restriction on the start of hay-making in speciesrich meadows is included in the management prescription for the Pennine Dales Environmentally Sensitive Area. (2) Historic start and finish dates for hay-making are given for the period 1945-86. Start dates are relatively constant throughout the period but finish dates are earlier towards the end of the period. (3) Analysis of the variation in vegetation in meadows on six farms indicates that the sequence in which the meadows are cut may have a major influence on their species composition, particularly if mineral fertilizers are not used. (4) Modelled phenologies are given for fifteen meadow species to assess the possible impact of different cutting dates on seed production. The results are discussed in the context of the comparative ecology of the main species and some modifications to the current management prescription are suggested.

Continuous, R-F induction selective hardening equipment

Restoration of diverse semi-natural grasslands is potentially limited by high availability of soil phosphorus (P). Successful targeting of restoration effort requires a knowledge of plant community tolerances to soil P availability. Many extraction methods for P availability have been developed but most are calibrated against the growth and P uptake of crop species grown in monoculture.To test which methods are most suitable for measuring available P in soils of mesotrophic grasslands, a bioassay experiment was undertaken to compare seven extraction methods with the growth and P uptake of grassland species. Five species were grown together on a soil treated to create a range of conditions of pH, mycorrhizal infection and P availability.Olsen P and Bray P were found to be significantly correlated with P uptake in plant growth across the range of soil treatments whilst ion exchange membrane P and resin P were significantly correlated with P uptake in plant growth in all but the calcareous soils. The acid extractions of Truog, acetic acid and EDTA–ammonium acetate were found to be less correlated with P uptake in plant growth. All extraction methods correlated more strongly with P uptake in the sterilised treatments than in those inoculated with mycorrhizal spores.The method of Olsen was therefore selected to analyse P availability in soils supporting a range of mesotrophic grassland communities from eleven sites across England. At each sampling location, the species composition of the vegetation was assessed and classified using the British National Vegetation Classification (NVC). Species-rich hay meadows across a range of alliances were found to occur on soils with low phosphorus availability. Species-poor communities, such as inundation grassland, were found to occur on soils with higher phosphorus availability. Pasture communities, of intermediate species richness, tended to occur on soils of intermediate phosphorus availability.Olsen’s method of P extraction is recommended for analysing soils of areas identified for habitat creation; values of less than 10 mg kg−1 will give the greatest potential for the restoration of species-rich mesotrophic grassland.