1) The effects of nitrogen dressing in various periods to the Criptomeria seedlings was studied. In the seedlings manured on 20 and 25 Aug., in this period the soil and atomospheric temperature was approximately 24°C, the growth of roots and sideslips was more promoted than that of central shoots. In this case, the amount of reducing sugar contained in the seedlings was remarkably decreased, and the moisture content was not increased. 2) To show the degree of long top growth, the writer gives following two new presentations. A: Length of the longest sideslip/Length of central shoot B: Number of branch on central shoot/Length of elongation of central shoot