Fig. 2. (a) Air temperature, (b) soil temperature, and (c) soil moisture in the top 5 cm of different tillage systems and residue covers from 7 to 26 Nov. 2001, after 3 yr in a corn–soybean rotation. For soil temperature, least significant difference (LSD) at P < 0.05 for each measurement time is provided; NS, not significant at P < 0.05. For soil moisture, an error bar for each measurement time is provided. NTR, no-tillage with residue; NTW, no-tillage without residue; ST, strip-tillage; DR, deep rip; CP, chisel plow; MP, moldboard plow.