Studies on the apple sod culture. II.
Survey of the sod apple orchards
1953 Volume 21 Issue 4 Pages 225-235
Details
1953 Volume 21 Issue 4 Pages 225-235
Surveys of the sod apple orchard were practiced during from April, 1949 to May, 1952 in the Aomori Apple Experiment Station and 95 sod apple orchards which are scattered all over Aomori Prefecture. The results obtained are summarized as follows:
1. The red clover in the sod apple orchards grew very vigorously and produced above 14.5 tons of the green matter per acre, based on the average of three years. The best growth of the red clover was obtained in the second growing year. The growth, however, lost vigor in haste from the third growth of the third growing year.
2. From the soil moisture determinations, the apple orchards are classified into two types-or-chards in which differences of the soil moisture content between the sod plot and tilled one were very scarce and those in which the soil moisture content of the sod plot was smaller than the tilled one greatly in the dry season, then it seemed that such difference for the soil moisture content was based largely on the soil properties pf the apple orchards, especially soil types.
3. One of the best assurances that the sod will not unduly compete with the apple trees for soil moisture was obtained from mowing the apple orchard frequently and mulching the cut cover crops around the tree or where the rover crops fell.
4. The distinct effects of the sod upon the tree vigor, yield of fruit, or fruits were not found out in these surveys. It was certain, however, that the tree in the sod of the dry land showed reduced vigor after the long drought, being attended with the yellowing of foliage color especially in May and July as compared with the tilled tree and that the fruit color of the sod was generally superior to that of the tilled tree.
5. During these surveys, it seemed that there was no outbreak of pests and diseases of the apples to be attributed in particular to the sod culture.
6. In the sod apple orchards investigated, roots of the red clover have penetrated the deep layer of the soil and were traced up to the depths of 90cm, about ninety percent of the whole being found out within about 30cm soil depths from the surface layer.
