Studies on the apple sod culture I

The growth of red clover in the too closely planted apple orchard

Abstract

1. In a too close planting apple seedling orchard in Aomori Apple Experiment Station, the growths of red clover under shady condition were investigated during the year 1949 and 1950, being compared with those in exposed field condion. Twenty Wagner pots were devoted to each block.
2. Until buds on the apple trees grew into the stage of “mouse-ear”, there had not been difference in the intensity of light measured with a rucksmeter between the too close planting orchard and the exposed field. After this, with the advance of flattening of apple leaves, the intensity of light in the orchard began to decrease, and in June when the leaves of the apple trees in the orchard completed their growth, it dropped to 50 per cent of the exposed field, the state continuing to fall.
3. In both these years, the decrease of the sun-light in the orchard had the corresponding growth of red clover, Thus, the harvest of red clover in the orchard was treated 20 days later than in the exposed field. But, concerning the height of red clover, the shady ones were taller than exposed ones.
4. In 1949, the green top weight of shady red clover was about 25 per cent of that grown in the exposed field; in 1950, at the frist harvest, 80 per cent, and at the second, 20 per cent.
5. As to those removed from pots, shady red clover showed about 20 per cent and 50 per cent of the growth of exposed ones in 1949 and in 1950.