In growing the mulberry tree, several small shoots are usually cut off in summer from each stock near the ground from which many shoots are regenerated every year. In the present experiment, the vertical distribution and its diurnal changes of air temperature were comparatively investigated in the two mulberry fields, the one being the field of the uncut-off control trees and the other being the field of the trees from which the small shoots had been removed.
On the soil surface and also on the point a little above the soil surface, the mean and maximum temperatures in the daytime and the temperature difference between the maximum and the minimum were found small shoots had been removed to be far higher in the field of the trees from which than in the control one. These results were retard to the facts that the solar radiation could not reach the soil surface in the case of the control field, while it could reach in the case of the tested field.