Effects of the Farm Work on the Growth and Yields of Vegetables

I. The direct effect of weeding operation on weed removal

Abstract

The direct effect of farm work F(t) can be expressed as a theoretical equation on t, the time after planting.
F(t)=1-G(t)-H(t)
where G(t)=∫^T_TNf_N(t)dt
H(t)=∫^TN_Of_O(t)dt
∫^T_Of_O(t)dt=1
and f_N(t): empirical equation on the removed effect level, after the operation. f_O(t): empirical equation on the removed effect level, without operation.
From this equation F(t), the theoretical maximum direct effect can be estimated. An experiment for the weeding effect on Japanese radish were conducted, to analyze practically this theoretical equation. As the results of analysis, it was clarified that the effect of a single weeding at two weeks after planting was 96.5% of the corresponding effect under weed-free condition throughout.