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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1. The method of leaf spraying of urea was applied on a grass land composed of mainly orchard gross, using one percent of water solution of urea in amount of two "kans" ("kan" equals 7.38 pounds) of urea nitrogen per "tan" ("tan" equals 0.245 acres). The application was performed in the data of 4th. to 8th. July 1954, when orchard grass was already grown to 10 inches high after first cutting. A largest increase in the yield of green crop (as second cutting) was observed in the 15th. to 20th. day after urea application, the increase being 36 percent. 2. The grass crap was found to change its water content even during short period of growing stage in summer. The grass to which urea spraying was applied showed to have always a higher water content than the control plant to which no urea was applied. 3. When calculated as air dried material, the increase of yield of grass caused by urea spraying corresponded to about 21% of control plant. 4. The grass crop to which urea was sprayed, indicated to contain a higher amount of both crude protein and pure protein than the control crop. Therefore such kind of grass, having a high amount of protein, is considered to be suited as substitutes of concentrates for dairy cattle. 5. The effect of leaf spraying of urea on the yield of crop tends to decrease as the plant growth advances, especially in such stage when the water content of whole plant became to show from 66 percent to 46 percent.

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