A HAY MEADOW IN WESTERN NORWAY - CHANGES IN THE COURSE OF A GROWING-SEASON

Interference of management with groups of species/single species in a hay meadow is studied in a pilot project. Plant species are recorded 3 times during growing season from 10 permanent plots at intervals along 2 transects crossing the meadow. Hult-Sernander-Du Rietz scale is used for estimating cover, and phenological phases are estimated according to Dierschke. The hay meadow is lightly fertilized in spring, mown once late in July and grazed lightly by calves in autumn. Until 7-8 years ago the meadow was more heavily grazed by sheep both in spring and autumn. 50 species are recorded, 44 within the permanent plots, 33 are indicators of agricultural management, 21 are indicators of traditional management, and 24 are adapted to grazing. The meadow belongs to Cardamino pratensis-Conopodietum majoris, subassociation campanuletosum. Luzula campestre, Campanula rotundifolia, Potentilla erecta, Hypochoeris radicata and Trifolium repens vary little in cover throughout the summer. Anthoxanthum odoratum, Leucanthemum vulgare, Trifolium pratense and Agrostis capillaris have a higher cover just before mowing than afterwards. Conopodium majus is not present above ground at all in August. Rumex acetosa and Achillea millefolium have their highest cover values in August. The time of flowering varied. At the spring analysis, Ajuga pyramidalis, Anthoxantum odoratum, Luzula campestre and Plantago lanceolata flowered. The main flowering took place at the end of June, when 20 species flowered. In August the flowers of Leontodon autumnalis, Hypochoeris radicata, Potentilla erecta and Hieracium vulgatum characterized the meadow. Several hypothesis and proposals for testing of the hypothesis are put forward.