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.
A hay crop was cut at three different dates in 1990 from a mesotrophic (meadow) grassland in Upper Teesdale, under various fertilizer, grazing and cutting 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. 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 cutting 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. Grazing and fertilizer treatments significantly affected seed numbers for a few species. Fifteen species showed significant (P < 0.01) declining linear trends in the amount of seed released by successive 24-hour shakes.