With extensive constructions of highway embankments being worked throughout the country in recent years improvement of the road side slopes with verdure has been the subject of studies. Application of fertilizer is urgently required for effecting improvement of the banks with verdure within a short period of time in order to prevent them from soil erosion in view of the fact that the soil to be vegetated is quite different from that of usual agricultural land, and that very steep slopes are under the plan of improvement with verdure.
It is deplorable that application of fertilizer to vegetate the area has so far been almost neglected. In the present paper first the geology of the soil of the embankments in Japan is dealt with respecting the road side slopes, and secondly the plant nutriment for vegetation of the banks is discussed with particular emphasis in detail on the three basic fertilizer elements. Finally the standard amount of fertilizer to be applied is discussed.
