1. The effect of leaf spraying method of urea on the growth and the cutting yield of elven kinds of forage crop was investigated. Amount of urea applied here was one "kan" ("kan" equals 7.38 pounds) of urea-nitrogen per "tan" ("tan" equals 0.245 acres). The time of urea application was dated the 11th-17th of may, 1953. 2. In legume crops such as white clover, ladino clover, alsike clover and red clover, a favourable effect was noted, showing increases of both the cutting height and cutting yeld. But in some legume crops such as trefoil species, only an increase of cutting yield was observed. 3. In grass crops such as tall meadow fescue and tall oat grass an increase of cutting yield was also found. In such case, the crops showed a marked increase of leaf numbers and, at the same time, an increase of leaf colour. But in some crops belonging to graminae, no change in cutting yield was observed; such fact was seen in kentucky 31 fescue, italian rye grass and velvet grass. The one of the reasons is considered to be the matter of urea spraying time, the adequacy of which will differ according to kinds of grass. 4. A chemical analysis was conducted and the amount of content of chlorophylls and carotenoid pigments was found to be larger in sprayed grass than in unsprayed grass. 5. The legume, when compared to grass, seemed to be more sensible to the injury of chemicals, showing a partial yellow change in leaf edge in few days after urea spraying. But such change disappeared rapidly within ten days and a vigorous increase of new leaves was seen, resulting the increase of total crop yield.
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