Die Bodenkultur - Journal for Land Management, Food and Environment

G. OBERGRUBER:

Effects of Mineral Nitrogen Fertilizing on Quality of Green Forage

Summary

39 green forage samples (each sample taken in 5 replications) are made in order to examine the effects of mineral nitrogen fertilizing on the digestibility of organic matter. In respect to the extensive grassland management desired this paper shows how extensification of nitrogen fertilizing influences the value of digestibility. With decreasing intensity of mineral nitrogen fertilizing the amount of grass declines in favour of the leguminosae. The results are a decrease of the crude fibre-contents and an increase of the digestibility of organic matter, most clearly to be seen at extensive kinds of utilization. More frequent cutting shows only small differences between the intensities of nitrogen fertilizing as far as energy contents are concerned. Regarding forage quality, the biggest advantage is the higher "elasticity of utilization" of more extensively used areas (= smaller decrease of quality caused by later used grassland). In spite of the higher "elasticity of utilization" of extensive fertilized areas an early cut is necessary in order to obtain a high energy value in the fodder. The values found refer to green forage only; losses in hay- or silage production have not been considered.