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A field study was conducted in Tanzania on a continuing five years old tillage trial to assess the residual effect of unmanured and manured tied ridges on some soil physical properties as well as on sorghum grain yield. Treatments tested were: no-till (NT), shallow tied ridges (STR), deep tied ridges (DTR) and annually made tied ridges (ADTR). The test crop was sorghum, variety, Tegemeo. There was no significant (P>0.05) difference in residual organic matter (OM) content among tillage treatments within unmanured and manured plots. Manure application significantly (P<0.05) affected sorghum grain yield. Compared to the control (No Primary Tillage with no FYM-NPT), yield was more than four times in the NPT+F (No Primary Tillage that received manure five years ago). Sorghum grain yield of the Control was significantly (P<0.05) increased by tillage methods. The annually made tied ridges had the highest grain yield of 2 t ha(-1) while control plots had 0.4 t ha(-1). In treatments referred to as having "residual tied ridges", the tied ridges were established in 1996/97 season and have been under experiment as residual tied ridges with very limited repair since then. Grain yield of 1.9 t ha(-1) under residual tied ridges after five seasons was statistically comparable to the yield from annually made tied ridges (ADTR). It was concluded that residual tied ridges could be utilized for up to five seasons for improved sorghum grain yield. The reduced tillage and the increased sorghum grain yield under the residual tied ridges are making the system attractive to farmers in semi-arid areas.