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

The results are reported from an experiment on the effects of cutting date (14 June, 21 July and 1 September), fertilizer application (none or 80 kg ha(-1) N plus 40 kg ha(-1) P and K) and grazing treat ments ( none, autumn or autumn plus spring) on the vegetation of an upland mes otrophic grassland in Upper Teesdale, northern England, UK. Effects on plant species number and cover Ne reported for 4 years (1989-93) of t reatment. Effects on 'species-attributes' are given for the fourth yea r. The cessation of grazing combined with the use of fertilizer progre ssively reduced species number by about 25%. Under traditional managem ent (no fertilizer, cutting date on 21 July, autumn and spring grazing ) the species number and cover remained relatively static over the 4 y ears. Comparison between treatments in the fourth year showed a reduct ion in species number under the fertilizer application, cutting date o n 1 September and no-grazing treatments. Fertilizer use together with cutting date on 1 September particularly lowered species number and co ver, Analysis of variance was used to assess the effect of treatment o n species that occurred frequently in the sward. A cutting date of 1 S eptember favoured Agrostis capillaris, Alopecurus pratensis, Poa trivi alis, 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 spec ies. These were primarily associated with the treatment combination th at matched 'traditional' management. Deviations from this 'traditional ' regime acted separately, rather than in combination, and favoured di fferent grass species. Traditional management was associated with rude ral, stress-tolerant ruderal and competitive ruderal strategists and w ith longer seed germination times, heavier seeds, some of which needed scarifying or chilling to break dormancy, and transient seed banks th at germinated in the autumn. The original sward was an Anthoxanthum od oratum-Geranium sylvaticum grassland, Briza media subcommunity (MG3b). After 4 years, Festuca ovina-Agrostis capillaris-Galium saxatile gras sland, Holcus lanatus-Trifolium repens subcommunity (U4b) and Lolium p erenne-Alopecurus pratensis-Festuca pratensis grassland (MG7c) were ro und in many of the fertilized and late-cutting treatments.