**2.3 Reduced tillage**

This type of operation allows minimum number of equipment passes along the cultivated area than the conventional tillage. This system employed in agricultural practice enables at least 15% but less than 30% coverage by surface residue after cropping.

### **2.4 Zero tillage**

In this system, the cultivated land is not manipulated throughout the cropping season. However, soil disturbance could result only during fertilizer incorporation and planting using seed drills, openers and coulters.

#### **2.5 Mulch-tillage**

Mulch-tillage refers to a practice of leaving 30% and above of crop remains on the top soil to enhance moisture on the soil, protect and reduce excess heat in the soil and generally maintain optimum soil condition. Different tillage equipment and tools are utilized during mulch-tillage, thereby enhancing and maintaining adequate soil water throughout the cropping season [22].

#### **2.6 Ridge-tillage**

In this type of system, the agricultural land is not manipulated throughout the season. Thus, fertilizer and seeds are applied on beds and ridges previously made in the last planting season using specialized equipment and tools, such as sweeps, disks and furrow openers. Weeding operation is carried out by the use of herbicides.

#### **2.7 Stale seedbed**

Stale seedbed production systems make use of full-width tillage after harvest, sometimes using tillage equipment comparable to the ones utilized during mulchtillage operation. In this system, ridges or beds are not manipulated but allowed to stale till the next cropping season. Contact herbicides are utilized in weeding. Preparation of land can take place in this system of tillage compared to mulch-tillage system. Thus, no further manipulation is done after the land preparation.

#### **2.8 Minimum tillage**

Minimum tillage has been used by the CT Workgroup [4]. It refers to a practice that reduces tillage passes, leading to conservation of fuel for a given crop by at least 40%. The minimum tillage system aimed at meeting up with the 40% and above decrease in the soil disturbance. As reiterated by the researchers in the University of California, 50% of fuel and 72% of time can be saved when utilizing the machine called "Incorpramaster" that operates on only one strip, in contrast to disk plowing and harrowing [2].

#### **2.9 Strip system**

In the strip system of tillage practice, tilling is done on the row where crops are to be planted. This is to make sure that crop remains are removed before it is tilled before planting to ensure residue removal, subsoiler usage, and most times allowing for crop land warming and drying.

### **2.10 Precision tillage**

In this type of tillage system, tillage is carried out exactly at the point(s) where it is required. Cost of tillage is greatly reduced since the number of tractor passes is limited; thereby fuel consumption is reduced.
